Induction of acrosome reaction by 4-Br-A23187 alters the glycoproteomic profile of boar spermatozoa

Protein glycosylation is a post-translational modification involved in wide range of biological processes. In mammalian spermatozoa this modification has been identified in numerous proteins, and membrane glycoproteins are involved in the fertilization process. The objective of the present study was to identify changes in protein glycosylation after acrosome reaction (AR) induction using the 4-Br-A23187 ionophore. Our results showed that treatment with 10 μM of 4-Br-A23187 for 20 min significantly increased the percentage of live acrosome-reacted spermatozoa compared to the control (69.8 ± 0.8 vs. 6.4 ± 0.5; mean % ± SEM, respectively). Also, we observed an increase in 32 kDa tyrosine-phosphorylated protein (p32) and a decrease in serine/threonine phosphorylation of the protein kinase A substrates (phospho-PKA-substrates) after ionophore treatment. Furthermore, changes in glycosylated proteins following AR induction were analyzed using different HRP-conjugated lectins (GNA, DSA, and SNA), revealing changes in mannose and sialic acid residues. Proteomic analysis of isolated proteins using GNA lectin revealed that 50 proteins exhibited significantly different abundance (q-value < 0.01). Subsequent analysis using Uniprot database identified 39 downregulated and 11 upregulated proteins in the presence of 4-Br-A23187. Notably, six of these proteins were classified as transmembrane proteins, namely LRRC37A/B like protein 1 C-terminal domain-containing protein, Membrane metalloendopeptidase like 1, VWFA domain-containing protein, Syndecan, Membrane spanning 4-domains A14 and Serine protease 54. This study shows a novel protocol to induce acrosome reaction in boar spermatozoa and identifies new transmembrane proteins containing mannose residues. Further work is needed to elucidate the role of these proteins in sperm-oocyte fusion.

Changes in environmental exposures over decades may influence the genetic architecture of severe spermatogenic failure

STUDY QUESTION

Do the genetic determinants of idiopathic severe spermatogenic failure (SPGF) differ between generations?

SUMMARY ANSWER

Our data support that the genetic component of idiopathic SPGF is impacted by dynamic changes in environmental exposures over decades.

WHAT IS KNOWN ALREADY

The idiopathic form of SPGF has a multifactorial etiology wherein an interaction between genetic, epigenetic, and environmental factors leads to the disease onset and progression. At the genetic level, genome-wide association studies (GWASs) allow the analysis of millions of genetic variants across the genome in a hypothesis-free manner, as a valuable tool for identifying susceptibility risk loci. However, little is known about the specific role of non-genetic factors and their influence on the genetic determinants in this type of conditions.

STUDY DESIGN, SIZE, DURATION

Case-control genetic association analyses were performed including a total of 912 SPGF cases and 1360 unaffected controls.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All participants had European ancestry (Iberian and German). SPGF cases were diagnosed during the last decade either with idiopathic non-obstructive azoospermia (n = 547) or with idiopathic non-obstructive oligozoospermia (n = 365). Case-control genetic association analyses were performed by logistic regression models considering the generation as a covariate and by in silico functional characterization of the susceptibility genomic regions.

MAIN RESULTS AND THE ROLE OF CHANCE

This analysis revealed 13 novel genetic association signals with SPGF, with eight of them being independent. The observed associations were mostly explained by the interaction between each lead variant and the age-group. Additionally, we established links between these loci and diverse non-genetic factors, such as toxic or dietary habits, respiratory disorders, and autoimmune diseases, which might potentially influence the genetic architecture of idiopathic SPGF.

LARGE SCALE DATA

GWAS data are available from the authors upon reasonable request.

LIMITATIONS, REASONS FOR CAUTION

Additional independent studies involving large cohorts in ethnically diverse populations are warranted to confirm our findings.

WIDER IMPLICATIONS OF THE FINDINGS

Overall, this study proposes an innovative strategy to achieve a more precise understanding of conditions such as SPGF by considering the interactions between a variable exposome through different generations and genetic predisposition to complex diseases.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the "Plan Andaluz de Investigación, Desarrollo e Innovación (PAIDI 2020)" (ref. PY20_00212, P20_00583), the Spanish Ministry of Economy and Competitiveness through the Spanish National Plan for Scientific and Technical Research and Innovation (ref. PID2020-120157RB-I00 funded by MCIN/ AEI/10.13039/501100011033), and the 'Proyectos I+D+i del Programa Operativo FEDER 2020' (ref. B-CTS-584-UGR20). ToxOmics-Centre for Toxicogenomics and Human Health, Genetics, Oncology and Human Toxicology, is also partially supported by the Portuguese Foundation for Science and Technology (Projects: UIDB/00009/2020; UIDP/00009/2020). The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

The Use of Non-Apoptotic Sperm Selected by Magnetic Activated Cell Sorting (MACS) to Enhance Reproductive Outcomes: What the Evidence Says

Sperm selection of the most competent sperm is a promising way to enhance reproductive outcomes. Apoptosis is the programmed cell death process to maintain tissue homeostasis, and MACS sperm selection of non-apoptotic cells enables the removal of apoptotic sperm from an ejaculate, thus leaving the non-apoptotic available to be microinjected, but given the associated costs of adding these sperm selection steps to the routine practice, there is a need for a careful examination of the literature available to answer questions such as who can benefit from this MACS, how significant this improvement is, and how robust the evidence and data available supporting this choice are. Thus, the aim of this narrative review was to objectively evaluate the available evidence regarding the potential benefits of the use of MACS. From the literature, there are controversial results since its implementation as an in vitro fertilization add-on, and this may be explained in part by the low quality of the evidence available, wrong designs, or even inadequate statistical analyses. We concluded that the benefits of adding MACS are unclear, and further methodologically sound research on specific populations is much needed before offering it clinically.

Oocyte rescue in-vitro maturation does not adversely affect chromosome segregation during the first meiotic division

RESEARCH QUESTION

Does rescue in-vitro maturation (IVM) in the presence or absence of cumulus cells, affect the progress of meiosis I, compared with oocytes that mature in vivo?

DESIGN

This prospective study was conducted in a university-affiliated fertility centre. Ninety-five young oocyte donors (mean age 25.57 ± 4.47) with a normal karyotype and no known fertility problems were included. A total of 390 oocytes (116 mature metaphase II [MII] and 274 immature oocytes) were analysed. The immature oocytes underwent rescue IVM in the presence of cumulus cells (CC; IVM+CC; n = 137) or without them (IVM-CC; n = 137), and IVM rate was calculated. Chromosome copy number analysis using next-generation sequencing (NGS) was performed on all rescue IVM oocytes reaching MII as well as those that were mature at the time of initial denudation (in-vivo-matured oocytes [IVO]).

RESULTS

Maturation rates were similar in IVM+CC and IVM-CC oocytes (62.8 versus 71.5%, P = 0.16). Conclusive cytogenetic results were obtained from 65 MII oocytes from the IVM+CC group, 87 from the IVM-CC group, and 99 from the IVO group. Oocyte euploidy rates for the three groups were similar, at 75.4%, 83.9% and 80.8%, respectively (P = 0.42).

CONCLUSIONS

The results suggest that culture of germinal vesicle and metaphase I oocytes in the presence of cumulus cells does not improve rates of IVM. In general, the process of rescue IVM does not appear to alter the frequency of oocytes with a normal chromosome copy number.

Influence of Sex and a High-Fiber Diet on the Gut Microbiome of Alentejano Pigs Raised to Heavy Weights

This study investigates the influence of sex and a dietary transition on the gut microbiota of a local Portuguese pig breed. Three groups of male Alentejano pigs (n = 10 each) were raised between ~40 and 160 kg LW. Group C included pigs that were surgically castrated, while the I group included intact ones; both were fed with commercial diets. The third group, IExp, included intact pigs that were fed commercial diets until ~130 kg, then replaced by an experimental diet based on legumes and agro-industrial by-products between ~130 and 160 kg. Fecal samples were collected two weeks before slaughter. The total DNA was extracted and used for 16S metabarcoding on a MiSeq® System. The dietary transition from a commercial diet to the experimental diet substantially increased and shifted the diversity observed. Complex carbohydrate fermenting bacteria, such as Ruminococcus spp. and Sphaerochaeta spp., were significantly more abundant in IExp (q < 0.05). On the other hand, castrated pigs presented a significantly lower abundance of the potential probiotic, Roseburia spp. and Lachnospiraceae NK4A136 group (q < 0.01), bacteria commonly associated with better gut health and lower body fat composition. Understanding the role of gut microbiota is paramount to ensure a low skatole deposition and consumers' acceptance of pork products from non-castrated male pigs.

Elevated Sperm DNA Damage in IVF-ICSI Treatments Is Not Related to Pregnancy Complications and Adverse Neonatal Outcomes

This multicenter retrospective cohort study assesses the effect of high paternal DNA fragmentation on the well-being of the woman during pregnancy and the health of the newborn delivered. It was performed with clinical data from 488 couples who had a delivery of at least one newborn between January 2000 and March 2019 (243 used autologous oocytes and 245 utilized donated oocytes). Couples were categorized according to sperm DNA fragmentation (SDF) level as ≤15% or >15%, measured by TUNEL assay. Pregnancy, delivery, and neonatal outcomes were assessed. In singleton pregnancies from autologous cycles, a higher but non-significant incidence of pre-eclampsia, threatened preterm labor, and premature rupture of membranes was found in pregnant women from the >15%SDF group. Additionally, a higher proportion of children were born with low birth weight, although the difference was not statistically significant. After adjusting for potential confounders, these couples had lower odds of having a female neonate (AOR = 0.35 (0.1-0.9), p = 0.04). Regarding couples using donor's oocytes, pregnancy and neonatal outcomes were comparable between groups, although the incidence of induced vaginal labor was significantly higher in the >15% SDF group (OR = 7.4 (1.2-46.7), p = 0.02). Adjusted analysis revealed no significant association of elevated SDF with adverse events. In multiple deliveries from cycles using both types of oocytes, the obstetric and neonatal outcomes were found to be similar between groups. In conclusion, the presence of an elevated SDF does not contribute to the occurrence of clinically relevant adverse maternal events during pregnancies, nor does it increase the risk of worse neonatal outcomes in newborns. Nevertheless, a higher SDF seems to be related to a higher ratio of male livebirths.

Influence of Sex on Meat and Fat Quality from Heavy Alentejano Pigs Finished Outdoors on Commercial and High Fiber Diets

This work aimed to examine the effects of sex on meat and fat quality traits from thirty Portuguese Alentejano (AL) pigs reared in outdoor conditions. These pigs were divided into three groups and fed ad libitum. From ~40 to 130 kg LW, castrated (C group) and intact animals (I and IExp) consumed commercial diets. Until slaughter (~160 kg), C and I pigs remained on commercial diets, and IExp changed to a more sustainable experimental diet with locally produced pulses and byproducts. Samples were collected from the Longissimus lumborum (LL), Psoas major (PM), and dorsal subcutaneous fat (DSF). At ~160 kg, the PM muscle of intact pigs presented lower intramuscular fat content than that of C pigs, while total collagen was higher. Additionally, PM myoglobin was lower and lightness (L*) was higher in intact pigs. Regarding DSF, moisture and total protein contents were higher and total lipids were lower in intact than in castrated pigs, while color parameters were not significantly different. Finally, antioxidant capacity measured in the LL muscle showed an overall lower value in intact pigs. However, lipid oxidation values were not significantly different between the experimental groups and only increased with storage time. Outdoor-reared intact AL pigs produced leaner and less saturated pork and fat compared to castrated ones. Despite the lower antioxidant activity observed in the LL muscles of intact pigs, the lipid oxidative stability of cooked meat was not different among the experimental groups.

Obstetrical and Perinatal Outcomes Are Not Associated with Advanced Paternal Age in IVF or ICSI Pregnancies with Autologous Oocytes

BACKGROUND

In recent years, there has been an evident delay in childbearing and concerns have been raised about whether this increase in age affects reproductive outcomes. This study aimed to evaluate the effect of paternal age on obstetrical and perinatal outcomes in couples undergoing in vitro fertilization or intracytoplasmic sperm injection using autologous sperm and oocytes.

METHODS

This retrospective study evaluated obstetrical and perinatal outcomes from 14,125 couples that were arbitrarily divided into three groups according to paternal age at conception: ≤30 (n = 1164), 31-40 (n = 11,668) and >40 (n = 1293). Statistics consisted of a descriptive analysis followed by univariate and multivariate models, using the youngest age group as a reference.

RESULTS

The study showed significantly longer pregnancies for the fathers aged 31-40 compared to ≤30 years. However, there were no significant differences for the type of delivery, gestational diabetes, anaemia, hypertension, delivery threat, premature rupture of membranes, preterm birth, very preterm birth, and the neonate's sex, weight, low birth weight, very low birth weight, length, cranial perimeter, Apgar score and neonatal intensive care unit admission.

CONCLUSION

Despite our promising results for older fathers, as paternal age was not associated with clinically relevant obstetrical and perinatal outcomes, future well-designed studies are necessary as it has been associated with other important disorders.

Transcriptomic Profiling of Subcutaneous Backfat in Castrated and Intact Alentejano Pigs Finished Outdoors with Commercial and Fiber-Rich Diets

In this work, we studied the backfat transcriptome of surgically castrated (C), intact (I) and intact fed an experimental diet (IE) outdoor-reared male Alentejano (AL) pigs. The experimental diet was a high-fiber diet with locally produced legumes and by-products associated with a boar taint reduction effect. At slaughter (~160 kg), backfat samples were collected for total RNA sequencing. Intact pigs presented leaner carcasses, more total collagen, and more unsaturated intramuscular fat content than C animals. A total of 2726 differentially expressed genes (DEGs, |log2 FC|> 0.58, q < 0.05) were identified between C and I with overexpressed genes related to muscular activity (MYH1, ACTA1) or collagen metabolism (COL1A1, COL1A2) in I pigs. Between C and IE, 1639 DEGs of genes involved in lipidic metabolism (LEP, ME1, FABP4, ELOVL6) were overexpressed in C. Finally, only 28 DEGs were determined between I and IE. Clustering results indicated a drastic influence of the testis in the transcriptome of subcutaneous fat of AL pigs, while the diet had a marginal effect. Diet can reduce stress by increasing satiety in animals, and could have induced an increase of skatole degradation due to the higher expression of the CYP2A19 gene in the IE group.

Outdoor Finishing of Intact Male Portuguese Alentejano Pigs on a Sustainable High-Fiber Diet: Impacts on Blood, Growth, Carcass, Meat Quality and Boar Taint Compounds

This trial evaluated the effect of sex on the blood, growth, carcass, meat quality, and boar taint compounds in male Alentejano (AL) pigs (n = 30). From ~40 to 130 kg LW, castrated (C) and intact pigs (I and IExp groups) were fed commercial diets ad libitum. Between ~130 and 160 kg (slaughter), C and I pigs continued on commercial diets, while IExp were fed an experimental diet containing locally produced pulses and by-products aimed at reducing boar taint. At ~160 kg, blood urea levels were higher in IExp than C pigs, triacylglycerols were lower in both intact groups, and cortisol was lower in IExp. IExp pigs exhibited faster growth, improved feed conversion ratio, carcass higher commercial yield and leaner meat than C pigs. The loin intramuscular fat in intact pigs was lower, less saturated and more polyunsaturated, while total collagen was higher. Fat androstenone content was higher in intact pigs and skatole content was similar across treatments, although they were below threshold values for consumer detection. Finally, although boar taint compounds were low in intact AL pigs raised outdoors, adding pulses and by-products to the experimental diet did not result in a reduction in fat skatole content compared to pigs fed the commercial diet.

Increased cytotoxic natural killer cells in the endometrium alone cannot be considered the immunological cause of recurrent miscarriage

OBJECTIVE

To study the distribution and gene expression of endometrial immune cell populations, especially natural killer (NK) subsets, between assisted reproductive technology patients and healthy donors and explore a possible relationship of these results with patients' killer cell immunoglobulin-like receptor (KIR) genotypes and KIR-human antigen leukocyte-C (HLA-C) binding.

DESIGN

Prospective observational cohort study.

SETTING

Clinic and university laboratories.

PATIENT(S)

Participants included 39 women with recurrent miscarriages who had undergone in vitro fertilization cycles with donated oocytes and 21 healthy oocyte donors with proven fertility.

INTERVENTION(S)

Endometrial biopsy samples were collected from both patients and donors, and the KIR genotypes of the assisted reproductive technology patients were analyzed.

MAIN OUTCOME MEASURE(S)

Endometrial gene expression (cluster of differentiation [CD] antigens and anti-inflammatory and proinflammatory interleukins) and the number and percentage of regulatory T and NK cell populations in patients and donors were determined. Subsequently, the results obtained were categorized in the group of patients by KIR genotype. Killer cell immunoglobulin-like receptor-HLA-C binding was also examined in patients, considering their KIRs.

RESULT(S)

A higher percentage of CD56dimCD16+ NK cells were observed in patients than those in healthy donors. Nevertheless, when categorizing patients by KIR genotype and comparing the KIR AA (35.9%), AB (43.6%), and BB (20.5%) groups, no statistically significant difference was observed in either endometrial gene expression or any of the immune cell populations analyzed. Finally, no differences in binding between KIR and HLA-C molecules were registered among these 3 sets of patients.

CONCLUSION(S)

The reported increase in the number of NK cells with a cytotoxic profile in the endometrium of women with a history of recurrent miscarriages cannot alone explain these events because no relationship is observed between such cellular increase and the KIR genotypes, which individually, and in combination with the different HLA-C alleles, have also been associated, by previous studies, with negative reproductive outcomes.

CLINICAL TRIAL REGISTRATION NUMBER

1405-MAD-025-JG.

Sperm epigenetics landscape: correlation with embryo quality, reproductive outcomes and offspring's health

Epigenetics refers to how gene expression and function are modulated without modifying the DNA sequence but through subtle molecular changes or interactions with it. As spermatogenesis progresses, male germ cells suffer plenty of epigenetic modifications, resulting in the definitive epigenome of spermatozoa conditioning its functionality, and this process can be altered by several internal and external factors. The paternal epigenome is crucial for sperm function, fertilization, embryo development, and offspring's health, and altered epigenetic states are associated with male infertility with or without altered semen parameters, embryo quality impairment, and worse ART outcomes together with the future offspring's health risks mainly through intergenerational transmission of epigenetic marks. Identifying epigenetic biomarkers may improve male factor diagnosis and the development of targeted therapies, not only to improve fertility but also to allow an early detection of risk and disease prevention in the progeny. While still there is much research to be done, hopefully in the near future, improvements in high-throughput technologies applied to epigenomes will permit our understanding of the underlying epigenetic mechanisms and the development of diagnostics and therapies leading to improved reproductive outcomes. In this review, we discuss the mechanisms of epigenetics in sperm and how epigenetics behave during spermatogenesis. Additionally, we elaborate on the relationship of sperm epigenetics with sperm parameters and male infertility, and highlight the impact of sperm epigenetic alterations on sperm parameters, embryo quality, ART outcomes, miscarriage rates and offspring's health. Furthermore, we provide insights into the future research of epigenetic alterations in male infertility.

How to select healthy sperm for intracytoplasmic sperm injection in samples with high sperm DNA fragmentation?

The body of evidence supports the negative impact of increased sperm DNA fragmentation (SDF) on natural fertility as well as assisted reproduction conditions. High SDF has been correlated with low pregnancy and delivery rates following intrauterine insemination. Also, high SDF is accused of reducing the rates of fertilization, implantation, pregnancy, and live birth following in-vitro fertilization (IVF). Despite no impact of high SDF on fertilization or pregnancy rates following intracytoplasmic sperm injection (ICSI), it has been correlated with poor embryo quality and a higher risk of miscarriage. Several methods have been introduced to help select sperm with the best DNA quality to be used in assisted reproductive technology procedures. These include magnetic-activated cell sorting, intracytoplasmic morphologically selected sperm injection, physiologic ICSI, and microfluidic sperm sorters, among others. This article aimed to discuss the impact of high SDF in infertile men on the reproductive outcome of couples undergoing IVF/ICSI. Additionally, this review highlights the principles, advantages, and limitations of different techniques that are currently used for the selection of sperm with intact DNA to be utilized for ICSI.

Differences in Muscle Lipogenic Gene Expression, Carcass Traits and Fat Deposition among Three Iberian Pig Strains Finished in Two Different Feeding Systems

The Iberian pig breed includes several well-differentiated strains. The present study evaluated carcass traits, fat deposition and muscle expression of important lipogenic genes (SCD, ME1, ACACA, FASN, EGR1, ACOX and ACLY) using 65 male pigs of 3 Iberian strains (20 Lampiño, 23 Torbiscal, and 22 Retinto) finished either in a conventional, concentrate-based system (CF) or in montanera (MF), a traditional free-range system with acorn feeding. Torbiscal had the highest ham, Longissimus thoracis and prime cuts yields, and the thinnest subcutaneous adipose tissue (SAT). Retinto had the highest monounsaturated fatty acids (MUFA) and percentage of intramuscular fat (IMF), while Lampiño had the greatest content of saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA), atherogenic (AI) and thrombogenic (TI) indexes in SAT. Conventionally finished pigs had the highest ham, L. thoracis and prime cuts yields, and SFA. Montanera-finished animals had the highest PUFA and MUFA contents, and the lowest AI, TI and n6/n3 ratio in SAT. In relation to gene expression, Retinto had the greatest SCD, FASN and ACLY levels. Most studied genes were overexpressed in CF pigs. In conclusion, MF pigs had healthier fat than CF pigs, and Retinto had the healthiest fat and the greatest lipogenic trend in muscle, supported by IMF and lipogenic gene expression.

Effect of incubation and analysis temperatures on sperm kinematics and morphometrics during human semen analysis

INTRODUCTION

Human semen analysis must be performed after the liquefaction of the ejaculate. This takes place about 30min after ejaculation and samples must be maintained in the lab during this time. The temperatures for this incubation and the final analysis of motility are crucial but seldom taken into account. This study aims to examine the effect of these temperatures on various sperm parameters both manually (sperm count, motility, morphology, viability, chromatin condensation and maturation and DNA fragmentation) and CASA (kinematics and morphometrics, using an ISAS®v1 CASA-Mot and CASA-Morph systems, respectively) analyzed.

METHODS

Seminal samples from thirteen donors were incubated for 10min at 37°C followed by additional 20min at either room temperature (RT, 23°C) or 37°C and then examined following WHO 2010 criteria.

RESULTS

The data obtained show that there were no significant differences (P>0.05) in the subjective sperm quality parameters with incubation temperature. On the other hand, the head sperm morphometric parameters were significantly higher after room temperature incubation showing, in addition, lower ellipticity (P<0.05). Furthermore, kinematic parameters were evaluated both at RT and 37°C for the two incubation temperatures. In general, the four temperature combinations showed that kinematic parameters followed this order: RT-RT<RT-37<37-37<37-RT (incubation and analysis temperatures respectively).

CONCLUSIONS

Our results showed that temperature control during both incubation and analysis is needed for accurate semen analysis, recommending the use of 37°C during the entire process.

Optimization of human semen analysis using CASA-Mot technology

The purpose of this study is to investigate the optimal framerate (FR) and the use of different counting chambers for improving CASA-Mot technology use in Andrology. Images were captured at 500 fps, then segmented and analyzed in several ranges of FRs (from 25 to 250) to define the asymptotic point that as an optimal FR. This work was replicated using counting chambers based in capillarity (disposable) or drop displacement (reusable) to study their effects on the motility results and kinematic values of the samples under the different experimental conditions. The α value (asymptote corresponding to FR_o) of the exponential curve was 150.23 fps, corresponding to a VCL of 130.58 mm/s, far from the value of 98.89 mm/s corresponding to 50 fps (the highest FR used by most current CASA-Mot systems). Our results have shown that, when using reusable counting chambers, type and depth have influence. In addition, different results were obtained depending on the area of image captured inside the different counting chamber types. To have reliable results in human sperm kinematic studies, almost 150 fps should be used for capturing and analyzing and differences between chambers should be considered by sampling from different areas, to obtain a representative value of the whole sample.

Advanced Paternal Age Does Not Affect Medically-Relevant Obstetrical and Perinatal Outcomes following IVF or ICSI in Humans with Donated Oocytes

BACKGROUND

Concomitant with delays in childbearing, concerns have been raised of whether advanced paternal age is associated with adverse reproductive outcomes, but the evidence is controversial in part due to the uncertain threshold in which to consider advanced paternal age and confounding maternal factors. This retrospective study aimed to evaluate the effect of paternal age on reproductive outcomes related to the pregnancy and perinatal health of the offspring.

METHODS

We retrospectively evaluated 16,268 cases of patients who underwent IVF or ICSI (using autologous sperm and donated oocytes, between January 2008 and March 2020, at Spanish IVIRMA clinics. Patients were divided based on paternal age at conception [≤30 (n = 204), 31-40 (n = 5752), and >40 years (n = 10,312)], and the differences in obstetrical and perinatal outcomes were analyzed by descriptive analysis, followed by univariate and multivariate analysis.

RESULTS

Fathers 31-40 and >40 years old were associated with lower odds of caesarean delivery [AOR 0.63 (95% CI, 0.44-0.90; p = 0.012) and AOR 0.61 (95% CI, 0.41-0.91; p = 0.017), respectively] and longer pregnancies [ARC 5.09 (95% CI, 2.39-7.79; p < 0.001) and ARC 4.54 (95% CI, 1.51-7.58; p = 0.003), respectively] with respect to fathers ≤30 years old. Furthermore, fathers aged 31-40 years old had lower odds of having a female infant (AOR, 0.70; 95% CI, 0.49-0.99; p = 0.045) than those ≤30. The rest of obstetrical and perinatal outcomes, which we deemed more medically-relevant as they were considered serious for health, were comparable between groups with our adjusted model.

CONCLUSIONS

Despite this hopeful message to fathers of advanced paternal age, future studies should consider the short- and long-term outcomes of the offspring and try to better elucidate the associations of advanced paternal age with reproductive outcomes and the molecular mechanisms underlying the observed associations.

Contribution of TEX15 genetic variants to the risk of developing severe non-obstructive oligozoospermia

Background: Severe spermatogenic failure (SPGF) represents one of the most relevant causes of male infertility. This pathological condition can lead to extreme abnormalities in the seminal sperm count, such as severe oligozoospermia (SO) or non-obstructive azoospermia (NOA). Most cases of SPGF have an unknown aetiology, and it is known that this idiopathic form of male infertility represents a complex condition. In this study, we aimed to evaluate whether common genetic variation in TEX15, which encodes a key player in spermatogenesis, is involved in the susceptibility to idiopathic SPGF. Materials and Methods: We designed a genetic association study comprising a total of 727 SPGF cases (including 527 NOA and 200 SO) and 1,058 unaffected men from the Iberian Peninsula. Following a tagging strategy, three tag single-nucleotide polymorphisms (SNPs) of TEX15 (rs1362912, rs323342, and rs323346) were selected for genotyping using TaqMan probes. Case-control association tests were then performed by logistic regression models. In silico analyses were also carried out to shed light into the putative functional implications of the studied variants. Results: A significant increase in TEX15-rs1362912 minor allele frequency (MAF) was observed in the group of SO patients (MAF = 0.0842) compared to either the control cohort (MAF = 0.0468, OR = 1.90, p = 7.47E-03) or the NOA group (MAF = 0.0472, OR = 1.83, p = 1.23E-02). The genotype distribution of the SO population was also different from those of both control (p = 1.14E-02) and NOA groups (p = 4.33-02). The analysis of functional annotations of the human genome suggested that the effect of the SO-associated TEX15 variants is likely exerted by alteration of the binding affinity of crucial transcription factors for spermatogenesis. Conclusion: Our results suggest that common variation in TEX15 is involved in the genetic predisposition to SO, thus supporting the notion of idiopathic SPGF as a complex trait.

Commercial Surrogacy: An Overview

OBJECTIVE

 Surrogacy is the process in which a woman carries and delivers a baby to other person or couple, known as intended parents. When carriers are paid for surrogacy, this is known as commercial surrogacy. The objective of the present work is to review the legal, ethical, social, and cultural aspects of commercial surrogacy, as well as the current panorama worldwide.

METHODS

 This is a review of the literature published in the 21st century on commercial surrogacy.

RESULTS

 A total of 248 articles were included as the core of the present review. The demand for surrogate treatments by women without uterus or with important uterine disorders, single men and same-sex male couples is constantly increasing worldwide. This reproductive treatment has important ethical dilemmas. In addition, legislation defers widely worldwide and is in constant change. Therefore, patients look more and more for treatments abroad, which can lead to important legal problems between countries with different laws. Commercial surrogacy is practiced in several countries, in most of which there is no specific legislation. Some countries have taken restrictive measures against this technique because of reports of exploitation of carriers.

CONCLUSION

 Commercial surrogacy is a common practice, despite important ethical and legal dilemmas. As a consequence of diverse national legislations, patients frequently resort to international commercial surrogacy programs. As of today, there is no standard international legal context, and this practice remains largely unregulated.

Switching to testicular sperm after a previous ICSI failure with ejaculated sperm significantly improves blastocyst quality without increasing aneuploidy risk

PURPOSE

The use of testicular sperm is confined to patients with azoospermia, but there is evidence to support its use in males with poor semen parameters and/or previous intracytoplasmic sperm injection (ICSI) failures with ejaculated spermatozoa. We compared the aneuploidy rate and quality between embryos derived from ICSI cycles with ejaculated sperm (EJ-ICSI) and those from ICSI cycles using testicular spermatozoa (TT-ICSI) within the same couple.

METHODS

Retrospective study of 27 couples who first underwent an EJ-ICSI cycle that did not result in a livebirth and afterwards a TT-ICSI cycle. Only the two closer cycles of each couple were included. Preimplantation genetic test for aneuploidies (PGT-A) was performed in both ICSI cycles and classic parameters of embryo quality were assessed until blastocyst-stage.

RESULTS

A total of 375 embryos from 54 ICSI cycles were evaluated. Aneuploidy rate was measured by two different parameters. Patients undergoing TT-ICSI presented a similar aneuploidy rate as EJ-ICSI group: 30.7% (23.4-38.0) vs 26.8% (18.1-35.5) per inseminated oocytes (P>0.05), and 76.2% (66.2-86.2) vs 72.1% (59.1-85.2) per the total number of biopsied embryos (P>0.05), respectively. Further, the good-quality blastocyst rate per correctly fertilized oocyte was significantly higher in TT-ICSI group (33.6% (30.4-36.9)) than EJ-ICSI group (24.2% (20.3-28.0)) (P<0.001).

CONCLUSIONS

Switching to testicular sperm for ICSI yielded better-quality blastocysts without affecting the chromosomal load of the embryos in non-azoospermic couples with a previous unsuccessful ICSI using ejaculated sperm. This strategy is a good option for couples seeking a livebirth who do not want to use donor sperm.

COVID-19 mRNA vaccines have no effect on endometrial receptivity after euploid embryo transfer

RESEARCH QUESTION

Does the COVID-19 vaccination affect endometrial receptivity after single euploid embryo transfer, measured by sustained implantation rate?

DESIGN

A retrospective cohort study analysing two groups of single euploid embryo transfers using own oocytes: one historical cohort of 3272 transfers 1 year before the pandemic; and one comprising 890 transfers in women previously vaccinated with mRNA vaccines against severe acute respiratory syndrome coronavirus 2. The main outcomes were clinical pregnancy rate (CPR) and sustained implantation rate (SIR) per embryo transfer. These outcomes were compared between non-vaccinated and vaccinated women, and women who had received one and two doses. Lastly, vaccinated women were divided into quartiles according to the time from last dose to embryo transfer.

RESULTS

Similar CPR and SIR were found between non-vaccinated and vaccinated women, and the odds ratio for both outcomes was not statistically significant after being controlled for potential confounders (OR 0.937, 95% CI 0.695 to 1.265 and OR 0.910, 95% CI 0.648 to 1.227 respectively). Within the vaccinated group, women who had received one or two doses also had similar outcomes. In addition, no differences were found according to the time interval from vaccination to embryo transfer.

CONCLUSION

The administration of mRNA vaccines against COVID-19 had no effect on endometrial receptivity and embryo implantation, regardless of the number of doses and time interval from vaccination to embryo transfer. The potential negative effect of the vaccine on endometrial receptivity and reproductive outcomes is reassuring for patients in the process of undergoing assisted reproductive treatment.

Sperm aminopeptidase N identifies the potential for high-quality blastocysts and viable embryos in oocyte-donation cycles

STUDY QUESTION

Is there a relationship between human sperm aminopeptidase N (APN) and embryo development in humans?

SUMMARY ANSWER

Human sperm APN could possibly become a new molecular biomarker for identifying the potential for high-quality and usable embryos.

WHAT IS KNOWN ALREADY

The diagnosis of male fertility is one of the major concerns of reproductive medicine. Approximately 30-40% of men with otherwise normal fertility parameters are still unable to achieve pregnancy. The predictive clinical value of semen analysis to identify fertile or infertile males is limited; therefore, new diagnostic methodologies for sperm are urgently required. Sperm APN may be a relevant molecular marker due to its high concentration in sperm cells and its important roles in sperm physiology, such as its functions in motility, acrosome reaction and embryo development.

STUDY DESIGN, SIZE, DURATION

This study included 81 couples who underwent oocyte-donation cycles at Clínica IVI Bilbao (Spain), yielding 611 embryos, between September 2014 and July 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

This study was conducted in an assisted reproduction unit and an academic research laboratory. All the semen samples were examined and classified following World Health Organization guidelines. Spermatozoa were isolated from semen using the discontinuous colloidal silica gradient (45-90%) technique. Embryo quality and development were determined according to the Spanish Association of Reproduction Biology Studies (ASEBIR) criteria. Human sperm APN levels were analyzed by quantitative and semiquantitative flow cytometry.

MAIN RESULTS AND THE ROLE OF CHANCE

The most well-developed and usable blastocysts were associated with low sperm APN levels. Semen samples that had lower APN levels generated more expanded, hatched and usable blastocysts and fewer early, arrested and non-usable blastocysts. The cumulative probability of having well-developed blastocysts increased by 1.38-fold at Day 5 and 1.90-fold at Day 6 of embryo development, and the likelihood of having usable embryos increased by 1.48-fold, when semen samples with low APN levels were used during the ICSI technique.

LIMITATIONS, REASONS FOR CAUTION

The data were obtained from a single fertility clinic. A multicentre study will be required to confirm the results.

WIDER IMPLICATIONS OF THE FINDINGS

Human sperm APN has the potential to become a new molecular biomarker to help identify the potential for high-quality embryos and diagnose male infertility, especially when seminal parameters are close to the threshold values. It could be a crucial tool for couples for whom the number of usable blastocysts is critical for ART success.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by grants from the Basque Government (GIC15/165) and the University of the Basque Country (UPV/EHU) (EHUA14/17). The authors declare that they have no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

O-186 Paternal age is significantly related with the type of delivery and the sex of the newborn in IVF or ICSI cycles with donated oocytes

Study question

Does paternal age have any effect on obstetric and perinatal outcomes in in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles with donated oocytes?

Summary answer

Newborn sex and type of delivery, but not other obstetric and perinatal outcomes measured, were significantly different when comparing our paternal age groups.

What is known already

Currently there is a delay in fatherhood that has led to an increase of the average male age at which the first child is conceived. Studies relating paternal age with reproductive risks are increasing and results are controversial leading to a need of more research about it, which this study tries to address. Studies considering treatments with donated oocytes (controlled female factor) allow for a better understanding of male factor and reproductive risks. These risks for the mother and offspring need to be properly assessed and therefore it is important to study whether they can be affected by paternal age.

Study design, size, duration

This retrospective observational multicentric cohort study has considered pregnancies and children conceived from donor IVF-ICSI performed to couples in Spain IVIRMA clinics between January 2008 and March 2020 using patients’ own sperm. Paternal age ranged from 21 to 54 years. The study population was divided in three groups: &lt;30(A, reference), 30-40(B) and &gt;40(C) years. The data available and included consisted of 16382 patients who had a delivery with a live birth and 17988 singleton newborns.

Participants/materials, setting, methods

We evaluated pregnancies and children from donor IVF-ICSI with own semen, known age and resulting in a delivery. Data were obtained from the patient’s clinical charts to build the database to analyze the main outcomes of the study. P &lt; 0.05 was considered statistically significant. We measured several obstetric and perinatal outcomes that were adjusted according to selected patients’, cycles’ and semen samples’ characteristics, as well as donor age, gestational age, type of delivery and newborn sex.

Main results and the role of chance

The analysis included: 233 newborns for A, 6539 for B and 11216 for C. Results are expressed as rate with 95%CI.

There were no statistically significant differences for the incidence of gestational diabetes, anemia, pre-eclampsia or preterm birth; newborn weight, length, cranial circumference, Apgar score (1, 5 and 10 min) and NICU admission between the reference younger group (A) and the older paternal age groups (B and C).

However, there were statistically significant differences for the incidence of hypertension between A 18.1%(10.5-28.1) and B 9.8%(8.8-10.9) with OR = 0.5(0.3-0.9)(p = 0.015); for delivery type between A[cesarean 44.0%(37.2-51.0)] and C[cesarean 64.0%(63.1-65.0)] with OR = 2.3(1.7-3.0)(p &lt; 0.001); and for newborn sex between A[female 55.1%(48.2-61.8)] and B[female 48.2%(46.9-49.4)] with OR = 0.8(0.6-1.0)(p = 0.047).

Therefore, these results suggest an increased risk of cesarean delivery in the older age group compared to the younger one and of having a male birth in the 30-40 group compared to the younger group. There was also a decreased risk of hypertension in 30-40 group compared to &lt; 30 group, which should be clarified in further studies.

After adjusted analysis, there were still significant differences for newborn sex between A and B (p = 0.048) and for delivery type between A and C (p = 0.043), but no significant differences for hypertension were observed.

Limitations, reasons for caution

Due to the retrospective nature of this study there are some biases derived from the clinical practice. Although there is some missing data limiting sample size, this is still large. Moreover, it considers donated oocytes (controlling female factors) limiting the generalization of our results to a population of young women.

Wider implications of the findings

Studies focusing on paternal age are increasing due to fatherhood delay, being results controversial. Paternal age comparison showed significant differences for hypertension, delivery type and newborn sex, however adjusted analysis only found an increased risk of cesarean delivery in C vs. A and of male newborn in B vs. A.

Trial registration number

NA

O-296 Paternal age does not affect obstetric and perinatal outcomes in IVF or ICSI cycles with autologous oocytes

Study question

Does paternal age have any effect on obstetric and perinatal outcomes in in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles with autologous oocytes?

Summary answer

Gestational diabetes, delivery type, cranial circumference and preterm birth were significantly different between our age groups, although after adjusted analysis no significant differences were seen.

What is known already

In recent years, there has been an increase of the average male age at which the first child is conceived. Therefore, studies addressing paternal age and reproductive risks are increasing and results are controversial, so there is a need of more research about it, which this study tries to address. Although several studies suggest the threshold to consider paternal age ‘advanced’ at 40 years, this limit is not well established. The assessment of risks concerning the mother and offspring is important and, thus, so is the study of its association with paternal age.

Study design, size, duration

This retrospective observational multicentric cohort study has considered pregnancies and children conceived from IVF-ICSI performed to couples in Spain IVIRMA clinics between January 2008 and March 2020 using patients’ own sperm and autologous oocytes. Paternal age ranged from 18 to 51 years. The study population was categorized in three groups: &lt;30(A, reference), 30-40(B) and &gt;40(C) years. The data available included 14402 patients who had a delivery with a live birth and 16118 singleton newborns.

Participants/materials, setting, methods

We evaluated pregnancies and children from autologous IVF-ICSI with own semen, known age and resulting in delivery. Data was exported to obtain the clinical database followed by the statistical analysis of the study main outcomes. P &lt; 0.05 was considered statistically significant. Obstetric and perinatal outcomes were measured including delivery type, incidence of preterm birth, gestational diabetes, anemia, hypertension and pre-eclampsia; and newborn sex, weight, length, cranial circumference, Apgar score and neonatal intensive care unit (NICU) admission.

Main results and the role of chance

Results are expressed as rate or mean with 95%CI.

There were no statistically significant differences for the incidence of anemia, hypertension or pre-eclampsia; newborn sex, weight, length, Apgar score (1, 5 and 10 min) and NICU admission between the reference younger group (A) vs. the older paternal age groups (B and C).

However, there were statistically significant differences for the incidence of gestational diabetes when comparing A 5.1%(3.5-7.2) with B 7.7%(7.1-8.3) with OR = 1.5(1.1-2.2)(p = 0.021) and with C 9.1%(7.1-11.4) with OR = 1.9(1.2-2.9)(p = 0.005); for delivery type when comparing A[cesarean 33.8%(31.3-36.4)] with B[cesarean 37.8%(37.0-38.7)] with OR = 1.2(1.1-1.3) (p = 0.004) and with C[cesarean 49.3%(46.7-52.0)] with OR = 1.9(1.6-2.2) (p &lt; 0.001); for cranial circumference when comparing A 34.5(34.3-34.7) with C 34.8(34.6-35.0) with p = 0.03; and for the incidence of preterm birth when comparing A 7.9%(6.6-9.5) with C 5.9%(4.7-7.2) with OR = 0.7(0.5-1.0)(p = 0.034).

These results suggest an increased risk of gestational diabetes and cesarean delivery as paternal age increases. Moreover, group C showed a larger cranial perimeter and a lower risk of preterm birth when compared to group A.

However, after adjusted analysis (according to selected patients’, cycles’ and semen samples’ characteristics, gestational age, newborn sex and type of delivery) these differences were no longer statistically significant, so probably other clinical variables are involved in the differences seen.

Limitations, reasons for caution

Despite the retrospective nature of this study that leads to biases derived from the clinical practice and to the presence of missing data limiting sample size, the study includes a huge sample size.

Wider implications of the findings

Currently, fatherhood delay has led to a growing interest in studies addressing paternal age and reproductive risks. Our paternal age comparison showed significant differences for gestational diabetes, delivery type, cranial circumference and preterm, no longer significant after adjusted analysis, so probably other clinical variables were involved. Further studies are needed.

Trial registration number

Not applicable

P-796 Intraovarian injection of plasma rich in growth factors improves ovarian reserve and reproductive outcomes in women with diminished ovarian reserve

Study question

Does Plasma rich in growth factors (PRGF) ovarian injection increase the ovarian reserve biomarkers in women with diminished ovarian reserve?

Summary answer

PRGF injection increased Antimüllerian hormone (AMH) levels and antral follicular count (AFC) since the first follow-up after treatment allowing the initiation of ovarian stimulation cycles.

What is known already

Several techniques based on in vitro activation, ovarian fragmentation and stem cell ovarian transplantation have been proposed to reactivate ovarian function and increase IVF success in women with premature ovarian insufficiency and poor ovarian response. However, less invasive and feasible approaches are still required for those patients where egg donation is the only practical option.

Platelet rich plasma (PRP) and PRGF contain a high concentration of platelets, which carry more than 800 types of proteins, cytokines, hormones, and chemoattractants. Indeed, intraovarian PRP injection has recently been used in different case series and cohort studies of POI women with encouraging results.

Study design, size, duration

Retrospective study with 104 women aging 23-45 years who received a PRGF intraovarian injection (REGENERA-Ovario) was conducted between 2020 and 2021 at IVIRMA Alicante (Spain). Study was approved by the IRB committee of La Fe University Hospital (2112-FIVI-109-SH).

Participants/materials, setting, methods

Patients underwent a PRGF injection (Endoret kit; B.T.I. Biotechnology Institute S.L, Spain) in both ovaries and a follow up of ovarian reserve biomarkers (AFC, AMH) and follicle stimulating hormone (FSH) to evaluate follicular reactivation seeking IVF or spontaneous pregnancy. The follow up visits ranged from 1 to 5 months and were developed on a monthly basis after treatment or after menses recovery in POI. Study variables were compared to basal levels with a paired t-test.

Main results and the role of chance

Overall, 104 women (age: 38.7±2.0 years; BMI: 22.1±2.9) with diminished ovarian reserves underwent a PRGF intraovarian injection (3.3±0.8ml PRGF/each ovary). Prior to treatment, our cohort was characterized high serum FSH (21.8±4.1mIU/mL), low AMH levels (0.25±0.37ng/ml), and an ovarian volume of 6.3±2.3cm3.

Eighty-eight of them fulfilled the 1st follow up visit and showed an increase of serum AMH (0.25±0.37ng/ml vs. 0.32±0.36ng/ml, p = 0.008), and AFC in both ovaries (2.1±1.9 vs. 3.2±2.4, p &lt; 0.0001) compared to basal levels, achieving ovarian reactivation in 55.9% of them and IVF cycle initiation in 19.3%. These improvements were higher 2 months after treatment (55 patients), with increased antral follicles (AFC-2: 2.9±2.5, p = 0.0001) and ovarian activation in 58.2%, and IVF start in 43.9% of patients. Similar results were observed during the 3rd follow up accomplished by 30 women and lasted until the 5th visit (n = 8), although the reduced patient number at this point.

A total of 44 IVF cycles were started and oocyte pick-up was successfully developed in 72.7% of them with a mean number of 3.3±4.2MII oocytes, 1.8±2.1 fertilized oocytes and 1.5±2.0 embryos per cycle. Indeed, 6 pregnancies were obtained during this period, 2 of them after embryo transfer and 4 by natural conception.

Limitations, reasons for caution

Our results are encouraging but a large cohort of patients with a longer follow up period is needed to establish the efficacy and duration of the PRGF positive ovarian effects. Moreover, a proper comparison with a control group with the same characteristics and no PRGF intervention is still required.

Wider implications of the findings

PRGF intraovarian injection reactivates follicle growth and allows IVF cycle initiation and embryo generation in a poor prognosis population of patients with diminished ovarian reserve. The effects persisted for several months after treatment.

Trial registration number

2112-FIVI-109-SH

P-538 KATNAL1 polymorphisms confer susceptibility to severe phenotypes of male infertility in a large European cohort

Study question

What is the contribution of the common variation of KATNAL1 to the development of severe spermatogenic failure (SPGF) in a phenotypically well-characterized cohort?

Summary answer

An allelic combination of KATNAL1 single-nucleotide polymorphisms (SNPs) increases the risk to develop SPGF, likely by altering the expression and splicing pattern of the gene.

What is known already

Spermatogenesis is a process that requires an exhaustive control of gene expression, and subtle alterations of its molecular regulatory network can lead to male infertility. The aetiology of most SPGF cases remains unknown, and increasing evidence clearly suggests that the idiopathic form of SPGF represents a complex trait, in which genetic susceptibility is conferred by the accumulation of risk alleles in genetically predisposed men. In this regard, previous studies reported that rare genetic mutations and polymorphisms in the KATNAL1 locus lead to male infertility through the disruption of microtubule remodelling and premature germ cell exfoliation.

Study design, size, duration

We designed a case-control genetic association study including three SNPs (rs2077011, rs7338931, and rs2149971) in the 3' and 5' regulatory regions of KATNAL1, which tagged the common genetic variability in the region. The allele frequencies in the study population, composed of 715 infertile men diagnosed with idiopathic SPGF, were compared to those observed in a control group comprising 1058 fertile men from Spain and Portugal.

Participants/materials, setting, methods

The SPGF group comprised 210 men with severe oligospermia (SO) and 505 with non-obstructive azoospermia (NOA). The latter were phenotypically characterised according to the histological examination of testis biopsies and its outcome (Sertoli cell-only syndrome, SCO; maturation arrest, MA; hypospermatogenesis, HS; and testicular sperm extraction, TESE). After genotyping, case-control association analyses by logistic regression were conducted. In silico functional characterization of risk variants was also carried out using public multiomic databases and bioinformatic tools.

Main results and the role of chance

Significant genetic associations with different SPGF patterns and/or TESE outcome were observed even after correction for multiple testing when independent SNP models were tested. However, in all cases, the haplotype model including the three risk alleles (rs2077011*C | rs7338931*T | rs2149971*A) was the most informative. This haplotype was specifically over-represented in the SPGF group (P = 3.45E-02, OR = 2.33), which includes all infertile men, and in the NOA group (P = 8.22E-03, OR = 2.97). In addition, subtype-specific associations were observed with the most severe subgroups, namely MA (P = 2.44E-02, OR = 5.00), SCO (P = 4.03E-03, OR = 5.16), and unsuccessful TESE outcome (P = 2.22E-04, OR = 6.13), which indicates the relevant role of KATNAL1 in spermatogenesis development. We prioritized the most likely causal variant/s based on in silico analyses addressing the possible functional implication of the tagged variants. We observed that an alteration of the KATNAL1 splicing pattern, by favouring the overrepresentation of a short non-functional transcript isoform in the testis, might be the cause behind the observed genetic association. The analysis of the testis transcriptome at the single cell level showed that KATNAL1 transcripts were mostly presented in spermatocytes and early spermatids at puberty, which correlates with its effect of premature exfoliation and loss of the germ cells.

Limitations, reasons for caution

Although a previous low-powered study reported suggestive associations between KATNAL1 and SPGF, additional genetic association studies in independent populations should be conducted to confirm our findings. Moreover, the statistical power for the overall analysis was appropriate, but the subphenotype analyses were performed with reduced power due to smaller study groups.

Wider implications of the findings

Our results suggest a relevant role of the common genetic variation of KATNAL1 in the susceptibility to develop the most severe histological phenotypes of NOA (i.e., SCO and MA). Studies like the one presented here may definitively help to develop future non-invasive molecular markers of TESE success.

Trial registration number

Not Applicable

P-694 Dosage of exogenous gonadotropins is not related to blastocyst aneuploidy or cumulative live-birth rates in PGT-A cycles

Study question

Does dosage of gonadotropins affect aneuploidy rate rates or cumulative live birth rates (CLBRs) after the transfer of euploid embryos?

Summary answer

We did not find evidence that dosage gonadotropin influenced significantly the rate of aneuploidy and CLBRs after transfer of euploid embryos.

What is known already

Aneuploidy rates increase steadily with age, reaching &gt;80% in women &gt;42 years old. The goal of controlled ovarian stimulation obtaining more embryos to biopsy through the recruitment of several follicles, reaching more euploid embryos. However, several studies have suggested that a high response to stimulation might be embryotoxic and/or increase aneuploidy rates by enhancing the abnormal segregation of chromosomes during meiosis. Furthermore, a study on young donors showed differences in the euploidy rates, suggesting an iatrogenic etiology resulting from different stimulation methods.

Study design, size, duration

A multicenter retrospective study, with the preimplantation genetic test for aneuploidy (PGT-A) between January 2013 and January 2020 collected from clinics IVIRMA in Europe. 6832 cycles of in vitro fertilization (IVF) with PGT-A were included in the study

Participants/materials, setting, methods

A total of 62131 embryos were analyzed for ploidy status. Embryos that were subjected to chromosomal analysis were performed blastomere by aCGH (array Comparative Genomic Hybridization) or NGS (Next-Generation Sequencing) analysis. The embryos were biopsied on days 5 and 6. Women were divided into two age groups (&lt;37 and ≥37 years old). Outcomes were compared between different total gonadotropin dosages (&lt;3000 and ≥3000 IU), the dosage of hMG, and numbers of oocytes retrieved.

Main results and the role of chance

The total number of aneuploid embryos was 28336 of the 62131 embryos genetically screened using PGT-A. The embryonic aneuploidy rate was 59.4% (95%CI 58.5-60.3). In the group of women with gonadotropins dosage &lt;3000 IU the embryonic aneuploidy rate was 59.7% (95%CI 58.7-60.8) and in the group with gonadotropins dosage ≥3000 IU was 58.7% (95%CI 57.1-60.3) with no significant difference between them (P = 0.279). In the group of younger patients (&lt;37 y.o) the aneuploidy rate demonstrated no significant differences between patients who received low gonadotropin dosages and patients with high gonadotropin dosages (P = 0.06). Aneuploidy rates in the group of older patients (≥37 y.o) were similar regardless of gonadotropin dosing (P = 0.21). Dividing the according to the number of oocytes retrieved (10, 11-15, &gt;15), the analysis of aneuploidy rate revealed no association between the gonadotropin dosages administrated depending on the total number of retrieved oocytes and age. The aneuploidy rate was also analyzed considering the administration of hMG, there was no statistical difference in the aneuploidy rate with low or high hMG dosages also when it was stratified by age. The cumulative live-birth rate in the groups of different gonadotropins dosage and different ages of patients was similar across the group.

Limitations, reasons for caution

The retrospective nature is the major limitation of this study, also patients included in the study received PGT-A using NGS and CGH arrays technology. The aCGH analysis used is less sensitive than more recent NGS technology.

Wider implications of the findings

Our study demonstrated that gonadotropin dosage did not affect aneuploidy rate or cumulative live-birth rates suggesting that the high doses of gonadotropins used in ART cycles may be safe.

Trial registration number

not applicable

P-536 Common variation in the PIN1 locus increases the genetic risk to suffer from Sertoli Cell Only syndrome

Study question

Are the common genetic variants located in the PIN1 region associated with human male infertility due to severe spermatogenic failure (SPGF)?

Summary answer

PIN1 gene polymorphisms may play a relevant role in the development of Sertoli Cell Only syndrome (SCO), the most extreme form of SPGF.

What is known already

PIN1 is a relevant prolyl isomerase in humans, that catalyzes cis/trans isomerization of peptide bonds. It has a central role in cell cycle progression and cancer, and it has been linked to the immune system promoting inflammation and reactive-oxygen species. Pin1 gene is highly expressed in adult mice testes, particularly in spermatogonia and Sertoli cells, and it is required to control the proliferation of spermatogonial stem cells. Additionally, it controls the integrity of the blood-testis barrier, helping to maintain the immune privilege of the testis. Nevertheless, mutations in PIN1 have not yet been described in human male infertility cases.

Study design, size, duration

A genetic association study was performed including samples from 715 men diagnosed with SPGF and classified as suffering from non-obstructive azoospermia (NOA, n = 505) or severe oligospermia (SO, n = 210), and 1,058 matched unaffected male controls from the Iberian Peninsula (Spain and Portugal). Allelic association on SPGF susceptibility were evaluated by testing three PIN1 single nucleotide polymorphisms (SNPs; rs2287839, rs2233678, and rs62105751), which tagged most of the common genetic variation present in this locus.

Participants/materials, setting, methods

Participants signed an informed written consent approved by the ethical committees of each participating center. SO and NOA were clinically defined according to the guidelines of the World Health Organization. Genomic DNA from blood samples was genotyped using TaqMan assays and statistical analyses were carried out by the means of logistic regression models. An in silico functional prioritization of the associated variants and their linked polymorphisms was also performed.

Main results and the role of chance

A subtype-specific genetic association with the subset of NOA patients classified as suffering from SCO was identified for the three analyzed genetic variants under the additive model (rs2287839: P = 1.94E-02, rs2233678: P = 1.94E-02, rs62105751: P = 1.94E-02). The minor alleles showed strong risk effects for this subset (rs2287839: OR = 1.85 [1.17-2.93], rs2233678: OR = 1.62 [1.11-2.36], rs62105751: OR = 1.43 [1.06-1.93]). Dependence analysis showed that all associated variants tagged the same signal. The variants underlying the identified association signal were prioritized based on their functional impact on the PIN1 locus, being rs3810166 the most likely candidate for functionality. The minor allele of such variant (G) is in linkage disequilibrium with the observed rs2287839-G risk allele and it is predicted to affect both gene expression and isoform balance of PIN1. The rs3810166 SNP likely influences the binding affinity of both HDAC2 and NRSF transcription factors, which are involved in cell cycle progression and transcription, respectively. Moreover, the tagged variants rs28802413 and rs10425775 were also predicted to alter the binding of significant transcription factors of the spermatogenic process, such as SIN3A and NANOG.

Limitations, reasons for caution

Although the overall statistical power of the study cohort was appropriate to detect the expected effects, the sample sizes in the subtype analyses were considerably lower, which may influence the obtained results. Further analyses including a larger SCO cohort should be performed to confirm our findings.

Wider implications of the findings

The obtained results shed light into the genetic contribution of common variation to male infertility, which may contribute to design a future panel of genetic markers to predict the testicular sperm extraction outcome, avoiding surgical interventions in NOA cases in which the probability of spermatozoa finding is much reduced.

Trial registration number

Not applicable

P-507 Psychosocial and motivational drivers of the increased IVF engagement of infertile couples following Covid-19

Study question

What are the main psychosocial motivational factors behind the increased IVF adoption during the Covid-19 Pandemic?

Summary answer

During the Covid -19 Pandemic more time invested in marital relationships prompted infertile couples to act and engage in IVF treatments.

What is known already

The Covid 19 Pandemic has generated a sense of lack of control and fear for the future in many individuals. However, like several life-threatening events, it could also have positive effects, motivating people to take significant actions for their life course. Little has been reported on the consequences that the Pandemic has generated on the infertile couple’s attitude toward reproduction, IVF treatments engagement and childbearing desire. We aimed to address if during the Pandemic, there was an increase of IVF demand and what motivational factors prompted infertile patients to pursue IVF as compared to the pre-pandemic.

Study design, size, duration

This is a prospective multicenter observational control-case study assessing the relational, emotional, and environmental motivational factors driving infertile couples to purse their first IVF treatment during the Covid-19 Pandemic in different IVF clinics as Valencia, Madrid, Rome, and Chile. To assess the growth rate in IVF activity at recruiting sites, number of cycles was compared over a 18 months period between the pre-pandemic and pandemic. The survey was run between September 2021 to January 2022.

Participants/materials, setting, methods

An ad hoc survey was developed to explore the main relationship, emotional and socioeconomical factors responsible for the IVF engagement. The electronic survey was delivered to 13585 patients attending the recruiting clinics from December 2018 to March 2020 for Prepandemic and from March 2020 to December 2021 for the Pandemic ones, and they were asked to rate their agreement for each answer on a five-points Likert scale.

Main results and the role of chance

For most clinics, data derived from national patients only showed a significant IVF demand increase (5.5-8.7%) for all indicators (number of started ovarian stimulations, oocyte pickups, and embryo transfers). Of 13685 patients receiving the survey only 1556 (810 prepandemic, 746 pandemic, response rate: 11%) completed it. Demographic and infertility history data (including male/female, infertility length, previous children and miscarriages, ethnicity) were homogeneous between two groups. However, the infertility length and the proportion of donation cycles were slightly lower in the pandemic group (2.3 vs 2.1) years and 24.1% vs 19% for pre-pandemic and pandemic, respectively; p &lt; 0.001). Only 25.34% (95%CI: 22.2-28.6) of Pandemic patients experienced their referral clinic closing, and 19.17% (95% CI: 16.4-22.1) public hospital closing, and 30.56% (95%CI:27.2-34.01) valued the use of telemedicine in the IVF positively. Interestingly, over 90.21% (95%CI:87.8-92.2) of pandemic patients started childbearing desire before the Pandemic, and about 68.63% (95%CI:65.1-71.9) knew already about their infertility. This suggests the Pandemic had represented a strong trigger for infertile patients to reframe their reproductive intention. Among all the motivational factors addressed in the survey, the increased time to invest in marital relationship was the stronger driver for pursuing IVF for Pandemic patients (OR:1.48; 95%CI: 1.16-1.89; p &lt; 0.01).

Limitations, reasons for caution

Not all potential drivers for IVF attainment have been included in the survey and unexplored factors might have played a role. Other reasons for caution include the possibility of response bias. However, the prospective design and the large multicentre/international setting of the study helped mitigating the effect of specific/local confounding.

Wider implications of the findings

The knowledge gathered here will be crucial to design more effective strategies to cope with patients’ needs during the pandemic. Furthermore, this study can provide a valuable resource for understanding psychosocial factors responsible of the ongoing decline in the natality rate in many developed countries, such as disincentivizing couples’ relationships.

Trial registration number

not applicable

Common genetic variation in KATNAL1 non-coding regions is involved in the susceptibility to severe phenotypes of male infertility

Background

Previous studies in animal models evidenced that genetic mutations of KATNAL1, resulting in dysfunction of its encoded protein, lead to male infertility through disruption of microtubule remodelling and premature germ cell exfoliation. Subsequent studies in humans also suggested a possible role of KATNAL1 single‐nucleotide polymorphisms in the development of male infertility as a consequence of severe spermatogenic failure.

Objectives

The main objective of the present study is to evaluate the effect of the common genetic variation of KATNAL1 in a large and phenotypically well‐characterised cohort of infertile men because of severe spermatogenic failure.

Materials and methods

A total of 715 infertile men because of severe spermatogenic failure, including 210 severe oligospermia and 505 non‐obstructive azoospermia patients, as well as 1058 unaffected controls were genotyped for three KATNAL1 single‐nucleotide polymorphism taggers (rs2077011, rs7338931 and rs2149971). Case–control association analyses by logistic regression assuming different models and in silico functional characterisation of risk variants were conducted.

Results

Genetic associations were observed between the three analysed taggers and different severe spermatogenic failure groups. However, in all cases, the haplotype model (rs2077011*C | rs7338931*T | rs2149971*A) better explained the observed associations than the three risk alleles independently. This haplotype was associated with non‐obstructive azoospermia (adjusted p = 4.96E‐02, odds ratio = 2.97), Sertoli‐cell only syndrome (adjusted p = 2.83E‐02, odds ratio = 5.16) and testicular sperm extraction unsuccessful outcomes (adjusted p = 8.99E‐04, odds ratio = 6.13). The in silico analyses indicated that the effect on severe spermatogenic failure predisposition could be because of an alteration of the KATNAL1 splicing pattern.

Conclusions

Specific allelic combinations of KATNAL1 genetic polymorphisms may confer a risk of developing severe male infertility phenotypes by favouring the overrepresentation of a short non‐functional transcript isoform in the testis.

Cumulative live birth rates in donor oocyte ICSI cycles are not improved by magnetic-activated cell sorting sperm selection

RESEARCH QUESTION

Does magnetic-activated cell sorting (MACS) for sperm selection increase cumulative live birth rates (CLBR) or improve clinical parameters of reproductive success in couples undergoing intracytoplasmic sperm injection (ICSI) with donor oocytes?

DESIGN

Retrospective multicentre observational study including data compiled from unselected couples who underwent ICSI cycles with donated oocytes in 15 Spanish IVIRMA fertility clinics (January 2008 to February 2020). Patients were divided into reference (standard semen processing, n = 40,157) and MACS (additional sperm selection step by MACS, n = 1,240) groups. CLBR were plotted on Kaplan-Meier curves and compared using the Mantel-Cox test. Proportions were compared with a generalized estimating equation model, and results were adjusted to clinically relevant variables.

RESULTS

The MACS group showed a 27.1% CLBR after one embryo was transferred and 81.6% after four; the reference group had CLBR of 19.6% and 78.5%, respectively. CLBR in the MACS group was 4.2% after five oocytes were used and 75.5% after 15; for the reference group, CLBR were 7.8% and 78.3%, respectively. Kaplan-Meier curves showed statistically significant differences in CLBR per number of embryos transferred and per number of donated metaphase II oocytes between the two groups (both P < 0.0001), but not for CLBR per embryo transfer. No significant differences between groups were found for classical clinical outcomes such as pregnancy and live birth rates per embryo transfer.

CONCLUSIONS

Although MACS sperm selection slightly increased the CLBR per embryo transferred compared with the reference group, this change was not clinically meaningful. MACS should not be recommended indiscriminately to all infertile patients undergoing ICSI with donated oocytes as a sperm processing add-on.

O-118 New insight into the genetic contribution of common variants to the development of extreme phenotypes of unexplained male infertility: a multicenter genome-wide association study

Study question

What is the contribution of the common genetic variation to the development of unexplained male infertility due to severe spermatogenic failure (SPGF)?

Summary answer

Genetic polymorphisms of key immune and spermatogenesis loci are involved in the etiology of the most severe SPGF cases, defined by Sertoli cell-only (SCO) phenotype.

What is known already

Male infertility is a rising worldwide concern that affects millions of couples. Non-obstructive azoospermia (NOA) and severe oligospermia (SO) are two extreme manifestations characterized by SPGF. A genetic cause can be established in only around 20% of affected men, with the remaining cases being classified as otherwise unexplained. To date, the genome-wide association study (GWAS) strategy, although already successfully applied in several other complex traits and diseases, was less fruitful in studies that attempted to decipher the genetic component of unexplained SPGF, mainly due to both a lack of well-powered samples in different ancestries and limitations in study design.

Study design, size, duration

We designed a GWAS for unexplained male infertility due to SPGF including a total of 1,274 affected cases and 1,951 fertile controls from the Iberian Peninsula (Spain and Portugal) and Germany. Different biostatistics and bioinformatics approaches were used to evaluate the possible effect of single-nucleotide polymorphisms (SNPs) across the whole genome in the susceptibility to specific subtypes of unexplained SPGF.

Participants/materials, setting, methods

The case cohort comprised 502 SO and 772 NOA patients, who were subdivided according to histological phenotypes (SCO, maturation arrest, and hypospermatogenesis) and the outcome of testicular sperm extraction techniques (TESE) from testis biopsies. Genotyping was performed with the GSA platform (Illumina). After quality-control and genotype imputation, 6,539,982 SNPs remained for the analysis, which was performed by logistic regression models. The datasets went through a meta-analysis by the inverse variance weighted method under fixed effects.

Main results and the role of chance

Genetic associations with SCO at the genome-wide-level of significance were identified in the major histocompatibility (MHC) class II region (rs1136759, OR = 1.80, P = 1.32E-08) and in a regulatory region of chromosome 14 nearby the vaccinia-related kinase 1 (VRK1) gene (rs115054029, OR = 3.14, P = 4.37-08). VRK1 is a relevant proliferative factor for spermatogenesis that causes progressive loss of spermatogonia when disrupted in mouse models. The role of the MHC system in SCO susceptibility was comprehensively evaluated through a validated imputation method that infers classical MHC alleles and polymorphic amino acid positions. A serine at position 13 of the HLA-DRβ1 protein (defined by the risk allele of the lead variant rs1136759) explained most of the SCO association signals within the MHC class II region. This residue is located in the binding pocket of the HLA-DR molecule and interacts directly with the presented antigen. Interestingly, position 13 of HLA-DRβ1 is the most relevant risk amino acid position for a wide spectrum of immune-mediated disorders. The HLA-DRB1*13 haplotype (which includes the serine at position 13 and represents the strongest NOA-associated marker in Asians to date) was the strongest signal amongst the classical MHC alleles in our study cohort (OR = 1.93, P = 9.90E-07).

Limitations, reasons for caution

Although the statistical power for the overall analysis was appropriate, the subphenotype analyses performed had considerably lower counts, which may influence the identification of genetic variants conferring low to moderate risk effects. Independent studies in larger SCO study cohorts should be performed to confirm our findings.

Wider implications of the findings

The molecular mechanisms underlying unexplained SPGF are largely unknown. Our data suggest a relevant role of common genetic variation in the development of SCO, the most extreme histological phenotype of NOA. SCO is characterized by the loss of germ cells and, therefore, implies a considerably higher probability of unsuccessful TESE.

Trial registration number

N/A

P–787 Impact of delaying ART to promote weight loss: a large multicentre study accounting for the combined effect of female/male age and body mass index (BMI)

Study question

Is postponing the start of ART (to promote a reduction in female BMI) beneficial for cumulative live birth rates (CLBR) when accounting for the female/male ageing this delay will cause?

Summary answer

Postponing ART treatment in one year to promote female weight loss could be detrimental in women of advanced maternal age (AMA, &gt;35 years-old).

What is known already

Overweight/obese couples are frequently encouraged to lose weight prior to infertility treatment to enhance ART outcomes. However, a meaningful weight loss is often difficult to achieve for these couples, frequently taking at least one year to accomplish. Given that both female and male ageing are also important for ART success, we were interested in understanding the combined impact on CLBR of BMI reduction and ageing following a one-year delay.

Study design, size, duration

A retrospective study including patients performing their first ART cycle using autologous gametes between 2013–2018 in one of 39 participating ART centres. Only GnRH antagonist cycles were included (n = 14260). CLBR was the primary outcome. Secondary outcomes included time-to-pregnancy, birthweight and gestational age.

Participants/materials, setting, methods

Patients were subdivided according to female BMI (Kg/m2) in either underweight (&lt;18.5), normal-weight (18.5–24.9), overweight (BMI 25.0–29.9 kg/m2) and obese (≥30 kg/m2). Meaningful and extreme weight loss were defined as a reduction from obesity to either overweight or normal-weight, respectively. We performed multivariable regression analysis to account for potential confounding.

Main results and the role of chance

Overweight (36.8%) and obese (33.0%) women had significantly lower CLBR when compared to the underweight (42.6%) and normal-weight (41.4%). When assessing the confounder-adjusted net-effect of male/female age and BMI, the predicted benefit of promoting a meaningful BMI reduction was lower than the estimated hindrance due to male/female ageing as soon as women reached AMA (n = 8365, 58.6%). This absence of benefit was especially important in women &gt;38 years-old, in which even extreme weight-loss did not compensate for the age-related reduction in CLBR caused by the one-year delay. Moreover, male weight-loss failed to provide any additional benefit when accounted for in the regression models. Finally, obesity was also associated with a modest but statistically significant one-month delay in time-to-pregnancy and a 96.1 g (95% confidence interval: 39.9–152.4) increase in birth weight. The diagram of predicted outcomes presented in this study may serve as a useful tool to counsel patients before treatment, namely when recommending treatment postponement to promote short-term (i.e. 3–6 months) or long-term (i.e. 1 year) weight loss.

Limitations, reasons for caution

Caution is recommended when extrapolating these results into everyday practice owing to the retrospective nature of the study and the fact that only GnRH antagonist cycles were included.

Wider implications of the findings: Patients are frequently confronted with the dilemma to either postpone treatment (and promote weight loss) or start treatment immediately (to avoid further ageing). Our results seem to show that women in AMA may have hindered CLBR if recommended to delay treatment even if the desired weight loss is ultimately achieved.

Trial registration number

Not applicable

P–080 Higher sperm DNA fragmentation reduces the proportion of good quality embryos at day 5 on IVF and ICSI cycles from unselected males

Study question

Does sperm DNA fragmentation (SDF) reduce the ratio of good-quality embryos in day 3 (D3) and day 5 (D5) of embryonic development?

Summary answer

High sperm DNA fragmentation (SDF &gt;15%) is associated with poor embryo quality at blastocyst-stage per cycle in unselected patients undergoing IVF and ICSI.

What is known already

It has been shown that the proportion of spermatozoa with DNA fragmentation is higher in infertile men than in semen from fertile men. However, the controversy regarding the impact that sperm genome damage can have on IVF or ICSI treatments is evident in the published literature. The effects of SDF would become evident after activation of the embryonic genome at 8-cell stage, compromising not only the quality of the embryos obtained, but also the reproductive outcomes, as reduced implantation rates, higher miscarriages rates and thus, a decreased chance of pregnancy.

Study design, size, duration

This multicentric observational retrospective study included 1339 couples who underwent 2759 IVF-ICSI cycles using autologous oocytes from January 2000 to March 2019. All men have an SDF test in their ejaculated spermatozoa by TUNEL assay (Terminal deoxynucleotidyl transferase dUTP nick end labeling). The subjects were divided into two groups according to their sperm DNA integrity: low (≤15%) (n = 2287 cycles) or high (&gt;15%) (n = 472) SDF.

Participants/materials, setting, methods

Embryo quality was assessed complying morphological standards at cleavage-stage on D3 and at blastocyst-stage on D5 (inner cell mass (ICM) and trophectoderm (TE) grade (A, B, C or D)) in according to ASEBIR’s embryo selection criteria, being embryos of good quality those categorized as A+B. The outcomes were calculated in relation to the total number of zygotes obtained. The results were compared by Student t test; p value &lt;0.05 was considered significant.

Main results and the role of chance

The SDF average of the low group was 5.8% (95% CI 5.6–5.9) whereas in high group was 23.7% (95% CI 23.0–24.4). The female age was equal, 37.1 years (95%CI 37.0–37.2) and 37.1 years (95% CI 36.8–37.4) respectively. A total of 9796 embryos were evaluated. The optimal cleavage-stage embryo rate per cycle was 25.0% (95% CI 21.7–28.3) (8.0 average cells number, 1.5 embryo fragmentation average, symmetry 1, mononucleated cells) versus 26.7% (95%CI 19.1–34.2) (7.9 average cells number, 1.8 embryo fragmentation average, symmetry 1, mononucleated cells) when comparing between groups (p &lt; 0.001). Blastocyst-stage arrival rate (number of embryos at D5) per cycle was 55.8% (95% CI 54.3–57.2) in ≤ 15% SDF group (embryo quality score was ICM A:12.1%, B:69.5%, C:8.8%, D:4.5%; TE A: 7.5%, B:42.2%, C:42.2%, D:8.1%) and 55.9% (95% CI 52.8–59.1) in the &gt;15% SDF group (ICM A:12.0%, B:68.7%, C:10.6%, D: 5.2%; TE A:9.1%, B:44.8%, C:37.8%, D:8.3%) (p &lt; 0.001). The good quality blastocyst rate per cycle was significantly higher in the group with SDF ≤15%, 27.7% (95%CI 26.5–29.0) versus SDF &gt;15% (27.4% (95%CI 24.6–30.2)). Of the total number of blastocysts, the proportion of A+B blastocyst was 60.5% (95% CI 58.3–62.7) and 64.2% (95% CI 59.2–69.2) (p &lt; 0.001), respectively.

Limitations, reasons for caution

The retrospective and multicenter nature of this study leads to uncontrolled biases derived from the clinical practice. Although the results were not adjusted for female’s age, it was not statistically different between groups. Embryo morphology evaluation was performed by senior embryologists, it still remains a subjective evaluation, though.

Wider implications of the findings: In this study, a higher amount of data was compiled so that a large number of embryos were analyzed. The DNA integrity of the sperm may be an important consideration when poor quality embryos were obtained in the previous cycle when deciding on the next clinical strategy to apply.

Trial registration number

NA

O-148 Sperm Aminopeptidase N as a predictive biomarker of blastocyst development and embryo viability

Study question

To evaluate human sperm APN as a prognostic factor for determining high-quality embryos.

Summary answer

The human sperm APN has the potential to become new molecular prognostic biomarker for having high-quality and viable embryos.

What is known already

Prognosis and diagnosis of male fertility is one of the major concerns in reproductive medicine. Approximately 30%-40% of men with otherwise normal fertility parameters are still unable to achieve pregnancy. The predictive clinical value of a semen analysis to identify fertile or infertile males is limited; therefore, new sperm diagnostic or prognostic methodologies are urgently required. Sperm Aminopeptidase N (APN) may be a relevant molecular marker due to its high concentration in sperm cells and its role in sperm physiology, such as motility, acrosome reaction, and embryo development.

Study design, size, duration

A prospective study that involves a total of 81 couples and 611 embryos who underwent oocyte-donation cycles at the Clínica IVI Bilbao (Spain) between September 2014 and July 2015.

Participants/materials, setting, methods

This study was set in an assisted reproduction unit and in an academic research laboratory. All semen samples were examined and classified following WHO guidelines. Spermatozoa were isolated from semen on discontinuous colloidal silica gradient (45%-90%) technique. Embryo quality and development were determined according to the Spanish Association of Reproduction Biology Studies (ASEBIR) criteria. Flow cytometry analyses of quantitative and semi-quantitative sperm human APN levels.

Main results and the role of chance

The obtained results proved that the most evolved and viable blastocysts were associated with low sperm APN levels. Expanding, expanded, hatching/hatched and viable blastocysts come from semen samples which showed lower APN levels than early blastocysts, blocked and non viable blastocyst. The cumulative probability of having more evolved blastyocysts increased 1.38-fold at day 5 and 1.98-fold at day 6 of embryo development as well as the likelihood of having viable embryo increased 1.48-fold when semen samples with low APN levels are used during the ICSI technique.

Limitations, reasons for caution

Data obtained from a single Fertility Clinic. A multi-centrum study will be required.

Wider implications of the findings

The human sperm APN has the potential to become new molecular prognostic biomarker for having high-quality embryos that could help to diagnose male infertility, especially when seminal parameters are close to the threshold values.

Trial registration number

Not applicable

P–329 Müllerian anomalies and embryo implantation in oocyte donation

Study question

Do patients with Mullerian anomalies (MA) who receive donated oocytes have different embryo implantation rate than patients with normal uterus?

Summary answer

In oocyte donation, patients with MA had lower implantation rate than patients with normal uterus.

What is known already

MA are associated with infertility and miscarriage but the mechanisms to explain this relation are not known. Some studies describe both oocyte and/or uterine factor. All studies describing the outcome in patients with MA, so far, are with own oocytes but none in oocyte donation.

Study design, size, duration

A multicentre restrospective cohort study from January 2000 to December 2019. Patients receiving donated oocytes were divided between those with MA (n = 473) according ESHRE classification and other group with normal uterus (n = 57 869). The primary outcome was implantation rate at fresh embryo transfer. Secondary aims were biochemical pregnancy rate, clinical pregnancy rate, ongoing pregnancy rate, miscarriage rate and live pregnancy rate.

Participants/materials, setting, methods

We considered the first oocyte donation cycle, without severe male factor, myomas, hydrosalpinx, Asherman syndrome, polyps or indication for preimplantational genetic diagnosis divided in two groups; patients with MA and no malformed uterus. MA group includes cycles of complete bicorporeal uterus (162), partial bicorporeal (30), bicorporeal septate (15), T shaped uterus (26), infantilis uterus (8), complete septate uterus (110), partial septate uterus (94) and hemi-uterus without rudimentary cavity (29).

Main results and the role of chance

We registered 58 342 patients from our oocyte donation program. Results are shown as mean and 95%CI and differences in pregnancy rates were expressed as relative risks (RR) with 95% CI being reference patients with normal uterus. In patients with MA, the implantation rate was different according the categories being significantly lower in patients with unicornuate uterus (0.29 95%CI: 0.14–0.43. p = 0.03). Biochemical pregnancy rate was significantly higher in patients with septate uterus (RR 1.51 (95%CI 1.02–2.22, p = 0.03) and significantly lower in unicornuate uterus (RR 0.49 (95%CI 0.27–0.90). No differences were found in clinical pregnancy rate among groups, but ongoing pregnancy rate and live birth rate were lower in unicornuate uterus ( RR 0.28 (95%CI 0.13–0.63, p = 0.002), (RR 0.32 (95%CI 0.14–0.73, p = 0.007) respectively. Miscarriage rate was significantly higher in patients with septate uterus (RR 1.78 (95%CI 1.18–2.68, p = 0.006)

Limitations, reasons for caution

As this was a retrospective cohort study, we were unable to study differences due to modifications in medical or laboratory protocols during this long period time. Different size of sample in some groups of MA makes impossible to translate conclusions to general population.

Wider implications of the findings: Our results indicate that there might be a defect in the embryo implantation rate in patients with MA depending on uterine factor. Different sample size among groups and some groups with scarce number of cases make less precise results. More studies controlling biases are needed to confirm our results.

Trial registration number

NCT04571671

P–615 The effect of late-follicular phase progesterone rise on embryo ploidy, embryo quality and cumulative live birth rates following a freeze-only strategy

Study question

Is late-follicular phase progesterone elevation (PE) associated with a deleterious effect on embryo euploidy, embryo blastulation and cumulative live birth rates (CLBRs)?

Summary answer

Late-follicular phase PE has no impact on impact on embryo euploidy rate, embryo blastulation rate nor on the CLBR.

What is known already

The effect of PE in ART outcomes has been extensively studied, yielding so far conflicting results. While some authors claim it is only detrimental to endometrial receptivity, others have suggested that it may also impair oocyte/embryo quality. Moreover, little is known regarding the potential effect PE may have on embryo ploidy and, consequently, CLBR.

Study design, size, duration

A multicenter retrospective cross-sectional study was performed between August 2017 and December 2019. A total of 1495 ICSI cycles coupled with preimplantation genetic diagnosis for aneuploidies (PGT-A) and deferred frozen embryo transfer (FET) were analyzed.

Participants/materials, setting, methods

All patients underwent ovarian stimulation with GnRH antagonist protocol and performed a serum progesterone measurement at one of the participating private fertility clinics on the day of trigger. The sample was stratified according to the progesterone levels: normal (≤1.50 ng/ml) and high (&gt;1.50 ng/ml). The primary outcome was the embryo euploidy rate. Secondary outcomes were the number of euploid blastocysts, the blastulation rate and CLBR.

Main results and the role of chance

Late-follicular phase PE was associated with higher late-follicular estradiol levels (2847.56±1091.10 pg/ml vs. 2240.94± 996.37 pg/ml, p &lt; 0.001) and more oocytes retrieved (17.67±8.86 vs. 12.70±7.00, p &lt; 0.001). The number of euploid embryos was higher in the PE group (2.32±1.74 vs. 1.86±1.42, p &lt; 0.001), whereas the embryo euploidy rate (48.3% [44.9%–51.7%] vs. 49.1% [47.7%–50.6%] and blastulation rate (47.1% [43.7%–50.5%] vs. 51.0% [49.7%–52.4%]) were comparable between the two groups. Likewise, no significant differences were found regarding the live birth rate (LBR) after the first FET (34.1% vs. 31.1%, p = 0.427) nor the CLBRs (38.9% vs. 37.0%, p = 0.637).

Mixed-model analysis was performed in order to account for the clustering of cycles in the same patient. Adjusting for patients’ age, PE and BMI, PE failed to demonstrate any effect on the embryo euploidy rate (OR 1.03 [95% CI 0.89–1.20]). Mixed-model analysis for the number of euploid embryos was also performed. After adjusting for PE, age, BMI and ovarian response, PE did not affect the number of euploid embryos (0.02 [95%CI –0.21;0.25]. Multivariate logistic regression adjusted for PE, age, BMI and ovarian response revealed that PE was not associated with the CLBR (adjOR 0.96 [95% CI 0.66–1.38]).

Limitations, reasons for caution

Limitations of the study include its retrospective nature. Moreover, including only GnRH antagonist protocol and ICSI does not allow the extrapolation of these results to other populations.

Wider implications of the findings: Our findings question results from previous studies claiming a detrimental effect of PE on embryo implantation potential. According to our results, PE has no impact on embryo euploidy rate, blastulation rate nor on CLBRs.

Trial registration number

Not applicable

P–087 Paternal age clinical effect on cumulative live birth rates (CLBR) per inseminated oocyte, embryo transfer and embryo transferred in autologous IVF-ICSI cycles of infertile males

Study question

Is reproductive success measured as CLBR per inseminated oocyte, per embryo transfer and per embryo transferred affected by paternal age in autologous IVF-ICSI cycles?

Summary answer

The number of embryo transfers and embryos transferred until live birth, but not the number of inseminated oocytes, were significantly different among the age groups.

What is known already

In recent years, there has been an increase of the average paternal age at which the first child is conceived. Therefore, there is a growing interest on the study of the impact of male age on the reproductive outcomes in assisted reproduction cycles (ART). Several studies have shown negative effects of advanced paternal age on semen parameters, embryo aneuploidy, miscarriage, male infertility,.... However, other studies have found no association between them. Hence, the impact of paternal age on reproductive outcomes still remains uncertain, leading to a need of more research on this topic, which this study tries to address.

Study design, size, duration

This retrospective observational multicentric cohort study has included autologous IVF-ICSI treatments (n = 6295) performed to couples with etiology of male infertility (non-normozoospermic) in Spain IVIRMA clinics between January 2008 and March 2020 using patients’ own sperm sample. Paternal age ranged from 20 to 75 years. The study population was categorized in 5 groups following the criterion of homogenizing the number of observations between groups: 20–34 (A), 34–37 (B), 37–39 (C), 39–42 (D) and 42–75 (E) years.

Participants/materials, setting, methods

Considering that male age could be a factor affecting reproductive outcomes, we evaluated men with different age that performed an autologous IVF-ICSI treatment with their own semen, etiology of male infertility and known age. Data was exported in order to obtain the clinical database and Kaplan-Meier was used for data analysis. P &lt; 0.05 was considered statistically significant. We measured reproductive success by CLBR per embryo transfer, per embryo transferred and per inseminated oocytes until live birth.

Main results and the role of chance

This study considered approximately 2976 patients and 4385 embryo transfers. The CLBR per inseminated oocyte showed no significant difference between the study groups: A (6.43%, 48.24%, 81.38%), B (5.74%, 52.14%, 82.87%), C (6.14%, 49.83%, 83.69%), D (5.89%, 53.60%, 81.16%) and E (6.61%, 47, 52%, 77.85%) for 4, 13 and 21/22 inseminated oocytes, respectively. In terms of CLBR per embryo transfer, the results obtained for each of the age groups were: A (31.81%, 71.89%, 87.63%), B (28.89%, 67.87%, 82.63%), C (27.10%, 68.87%, 88.17%), D (23.45%, 64.63%, 100.00%) and E (22.88%, 55.48%, 63.31%) for 1, 4 and 7 embryo transfers, respectively. There were statistically significant differences in the CLBR per embryo transfer between the studied age groups (p &lt; 0.0001). CLBR per embryo transferred for each age group was as follows: A (10.85%, 60.53%, 80.88%), B (9.34%, 59.75%, 78.23%), C (11.89%, 57.63%, 74.97%), D (10.25%, 52.71%, 77.76%) and E (11.71%, 51.50%, 71.51%) for 1, 4 and 7 embryos transferred, respectively. As in the case before, there were statistically significant differences in the CLBR per embryo transferred between the age groups (p &lt; 0.05). The findings presented highlight that the increase in paternal age could be affecting the reproductive outcomes in IVF-ICSI cycles using autologous oocytes.

Limitations, reasons for caution

The retrospective nature of this study leads to biases derived from the clinical practice and to the presence of missing data (limiting sample size). Moreover, this study considered autologous cycles, therefore the results were not adjusted for female factors.

Wider implications of the findings: Our study showed that reproductive outcomes measured by CLBR per embryo transfer and embryo transferred until live birth were significantly different between the paternal age groups in autologous IVF-ICSI cycles of infertile males. Hence, paternal age could be affecting reproductive outcomes and it should be considered for improving infertility counselling.

Trial registration number

NA

O-210 Sperm DNA fragmentation (SDF) is not associated with adverse maternal and neonatal outcomes in IVF-ICSI cycles with autologous oocytes

Study question

Does an elevated SDF (&gt;15%) increase the odds of adverse maternal and neonatal outcomes in autologous oocyte IVF-ICSI cycles from unselected couples?

Summary answer

No adverse effects of high SDF on obstetric and neonatal outcomes have been found in couples with sperm fragmentation undergoing IVF-ICSI cycles with own eggs.

What is known already

Sperm chromatin integrity assessment has been implemented as an additional tool in the clinical evaluation of sperm quality in infertile patients undergoing an assisted reproduction treatment. All of the published reports to date appraise its effect on clinical outcomes, and how it impacts embryo quality and the pregnancy chances after IVF and ICSI cycles. Sperm DNA integrity has also been hypothesized to affect offspring health but not many studies have reported in humans if an elevated SDF raises the risks of obstetric, delivery and neonatal outcomes.

Study design, size, duration

Multicentric retrospective cohort study of all IVF-ICSI cycles using autologous oocytes between January 2000-March 2019 at Spain IVIRMA clinics of couples with a SDF test on their ejaculated semen. The sperm fragmentation index was measured in all men with TUNEL assay. The database included 228 couples which had a delivery with at least a newborn. Subjects were divided into two study groups according to their level of SDF: ≤15% (low SDF) or &gt; 15% (high SDF).

Participants/materials, setting, methods

Patients with missed information on maternal and neonatal outcomes were not counted for the analysis. The obstetric outcomes were gestational age, gestational diabetes, preeclampsia (hypertension with proteinuria after 20 weeks of gestation) and type of delivery. Neonatal outcomes were sex, birth weight, length, head circumference, Apgar score at 1, 5, 10 minutes, and neonatal intensive care unit (NICU) admission. Student’s t-test and Fisher’s test were used for statistical analysis. A p-value&lt;0.05 was considered statistically significant.

Main results and the role of chance

Maternal age mean was 37.4 years (95%CI 36.9-38.0) in ≤ 15%SDF group and 37.2 years (95%CI 36.1-38.4) in &gt; 15%SDF group (p = 0.8). Similar gestational age was found, 41.8 weeks (95%CI 41.3-42.2) in ≤ 15%SDF and 41.3 weeks (95%CI 40.4-42.3) in &gt; 15%SDF. Gestational diabetes incidence was higher in &gt; 15%SDF compared to ≤ 15%SDF group (3.5% versus 1.7% (OR = 2.0 (95%CI 0.03-39.8), p = 0.5). Equally, the incidence of preeclampsia was 3.6% in patients with high SDF versus 1.7% in couples with low SDF, OR = 2.1 (95%CI 0.03-41.3), p = 0.5. Type of delivery frequency was in the ≤15%SDF group 61.9% vaginal and 38.1% cesarean, while in the &gt;15%SDF group 62.1% vaginal and 37.9% cesarean (OR = 1.0 (95%CI 0.4-2.6), p = 1.0). The overall proportion of singleton pregnancies was 87.2% (95%CI 82.4-91.2) and twins 12.8% (95%CI 8.8-17.6). There were no statistically differences between groups in the rate of delivery of twins and in the sex ratio of the newborns. When comparing the newborns of ≤ 15%SDF with &gt;15%SDF group, the average of weight was 3011.7g (95%CI 2912.2-3111.2) versus 2986.4g (95%CI 2753.1-3219.7), of length was 49.2cm (95%CI 48.3-50.0) versus 49.5cm (95%CI 49.2-49.9), of head circumference was 34.9cm (95%CI 34.6-35.2) versus 34.3cm (95%CI 33.4-35.2). No statistically differences were observed for Apgar punctuation and for NICU admission.

Limitations, reasons for caution

Due to the retrospective nature of the study we have missing data from the lack of follow-up of many patients after the confirmation of the ongoing pregnancy. Although pregnancies of couples with elevated SDF have a higher incidence of gestational diabetes and preeclampsia, the sample size evaluated is a limitation.

Wider implications of the findings

This is one of the first reports to evaluate the relationship between paternal DNA damage and obstetric risks and neonatal health in couples with high SDF who underwent IVF-ICSI in our centers. Despite SDF did not jeopardize the maternal and neonatal outcomes, more studies are needed to confirm this conclusion.

Trial registration number

NA

P–005 Magnetic-activated cell sorting in couples undergoing preimplantation genetic testing for aneuploidies (PGT-A) using autologous oocytes shows slightly lower aneuploidy rates compared to standard semen processing

Study question

Does the selection of non-apoptotic sperm via magnetic-activated cell sorting (MACS) reduce the aneuploidy rate of embryos from couples undergoing ICSI cycles with PGT-A using the patients’ own oocytes?

Summary answer

It does. The aneuploidy rate in the MACS group was 4.34% lower than the one obtained using semen samples processed according to standard clinical practice.

What is known already

MACS is a successful tool in eliminating proapoptotic sperm from a semen sample. However, the true effect of this technique on reproductive outcomes and the quality of the resulting embryos are a matter of controversy. Some studies report that its use improves the percentage of good quality blastocysts in women older than 30 years old compared to standard ICSI. Randomized clinical trials that compare MACS to a control sample consider parameters of embryo quality such as morphology at day 3 or day 5, symmetry of the blastomeres, blastocysts’ stage of expansion, but they do not consider embryo ploidy.

Study design, size, duration

Retrospective, multicentre, observational cohort study. 14,145 patients and 18,710 cycles were evaluated in the reference group. In the MACS group, 615 patients and 974 cycles were considered. Data were exported from cycles performed in Spanish IVIRMA clinics between January 2008 and February 2020.

Participants/materials, setting, methods

Unselected males in couples undergoing PGT-A cycles, then subdivided into male factor (MF) - total progressive motile sperm count lower than 5 million - and non-male factor (NMF) infertility. Statistical analysis performed using R v.4.0.0. Means were calculated and compared using two-tailed paired t-test, while proportions were compared using Fisher’s exact test and the chi-squared test and the appropriate correction for multiple comparisons. The aneuploidy rates for each group were compared using Fisher’s exact test.

Main results and the role of chance

In the control group 73,228 biopsied embryos, from which 71,439 were informative in the PGT-A. In the MACS group 3,919 biopsied embryos, from which 3,843 were informative. The aneuploidy rate, computed per informative embryo, was 68.87% (68.40%, 69.34%) in the reference group and 64.53% (62.43%, 66.64%) in the MACS group. Both comparisons were statistically significant (p-value ˂0.00001). According to these results, an embryo in the PGT-A programme using non-apoptotic sperm selected through MACS and autologous oocytes had a 5% less chance of being aneuploid than those embryos fertilised with standardly selected sperm (relative risk of 0.95 (0.91–0.98) p = 0.006769). Embryos conceived from NMF patients whose semen had been processed using MACS had a 4.27% lower aneuploidy rate than the reference (65.52% (63.16%, 67.88%) vs 69.79% (69.20%, 70.37%) respectively). This difference was statistically significant. Those embryos conceived using semen from patients with MF using MACS also showed a lower aneuploidy rate than the reference with MF (0.28% (55.48%, 65.08%) vs (64.94% (63.35%, 66.23%) respectively), although this difference was not statistically significant. Thus, the decrease in aneuploidy rate observed when comparing MACS and reference groups undergoing PGT-A cycles using autologous oocytes remained approximately the same in both MF and NMF semen samples.

Limitations, reasons for caution

The retrospective nature of the study subjects the data to biases or inaccuracies in their annotation in the clinics’ informatic platform from which they were exported. However, the statistical analysis aimed at controlling these biases as much as possible.

Wider implications of the findings: The vast amount of data compiled for this study confirms that the selection of non-apoptotic sperm through MACS slightly decreases the aneuploidy rate of embryos compared to semen samples processed according to the clinics’ standards. This would be interesting for patients who are considering undergoing PGT-A cycles in the future.

Trial registration number

Not applicable

P–030 A sperm chromatin damage &gt;15% negatively impacts on the quality of embryos obtained from ovum donation ICSI cycles of unselected couples

Study question

Is embryo quality downgraded in couples with elevated sperm DNA fragmentation (SDF) in the ejaculated semen of male partner using donated eggs?

Summary answer

The rate of good quality embryos at day 3 and blastocyst-stage is statistically inferior in males with SDF&gt;15% undergoing ICSI cycles with donated oocytes.

What is known already

The effect of a damaged paternal chromatin will be shown from the 8-cell stage of embryo development, a time which the genome of the embryo is transcriptionally active. Fertilization with a spermatozoon with fragmented DNA may impair the quality of the embryos obtained per cycle, and therefore reduce the chances of pregnancy. The use of donated oocytes is an ideal model to evaluate the real effect of SDF on embryo quality by standardizing the female factor. In addition, we have a large cohort of ovum donation cases in our history, which allows a more proper evaluation of the effect.

Study design, size, duration

Retrospective multicentric study including the clinical data of 864 couples of ovum donation program who underwent 1903 ICSI cycles between January 2000 and March 2019. The DNA fragmentation of their ejaculated spermatozoa was measured by TUNEL assay (Terminal deoxynucleotidyl transferase dUTP nick end labeling). Two study groups were created according to the SDF level: ≤15% (low) (n = 1626) or &gt; 15% (high) (n = 277).

Participants/materials, setting, methods

Embryos were evaluated throughout embryonic development according to classical morphological parameters at day 3 (D3), on cleavage-stage, and at day 5 (D5), on blastocyst-stage (trophectoderm (TE) and inner cell mass (ICM)), following ASEBIR guidelines, categorized from A to D. Embryos scored as A and B were considered to be good quality. The proportion of embryos was calculated according to the total number of correctly fertilized oocytes or zygotes. A p &lt; 0.05 was considered significant.

Main results and the role of chance

A total of 6130 embryos were evaluated. The SDF average of ≤ 15% group was 5.9% (95%CI 5.7–6.1) and 24.3% (95%CI 23.2–25.3) in the &gt;15% group. The cycle-related characteristics and the seminal parameters were comparable. The proportion of optimal cleavage-stage embryo (number of A+B embryos at D3) per cycle was 21.7% (95%CI 19.0–24.5) (8.1 average cells number, 0.8 embryo fragmentation average, symmetry 1, mononucleated cells) in ≤ 15% SDF group versus 21.1% (95%CI 13.9–28.3) (8.2 cells number average, 1.3 embryo fragmentation average, symmetry 1, mononucleated cells) (p &lt; 0.001). The blastocyst-stage arrival rate (number of embryos at D5) per cycle was higher in the &gt;15% SDF group (p &lt; 0.001), 53.4% (95%CI 48.8–58.1) (TE quality A:20.5%, B:42.5%, C:22.7%, D:14.8%, and the ICM quality A:26.1%, B:52.1%, C:13.2%, D:6.2%) versus 49.9% (95%CI 48.1–51.6) (TE quality A:21.1%, B:42.8%, C:21.85, D:14.1% and ICM A:26.6%, B:55.5%, C:11.1%, D:4.7%) in the low SDF group. The rate of good quality blastocyst (number of quality A+B embryos in D5) per cycle was significantly higher in the couples with low SDF (24.8% (95%CI 23.6–25.9)) than in those with elevated SDF (23.5% (95%CI20.9–26.2)) (p &lt; 0.001). Accordingly, the A+B blastocyst rate divided by the total number of blastocysts was 59.1% (95%CI 56.7–61.4) versus 55.9% (95%CI 49.9–62.0) (p &lt; 0.001), respectively.

Limitations, reasons for caution

The main limitation is that retrospective design of the study may not eliminate the potential unaccounted-for bias derived from the clinical practice of multiple centers even though both groups were statistically comparable. Also, the assessment of embryo quality is still remaining highly subjective to embryologists.

Wider implications of the findings: Although the effect size is small, it may be useful in clinical practice when an ICSI cycle yields no good-quality embryos, as one of the underlying causes of that fact. Knowing the SDF level can be a helpful tool in making subsequent clinical decisions aimed at improving outcomes for couples.

Trial registration number

Not applicable

P–723 Ovarian reserve parameters and ovarian stimulation outcome for IVF/ICSI are influenced by ethnicity

Study question

Are the ovarian reserve parameters and the outcome of ovarian stimulation for IVF / ICSI influenced by ethnicity?

Summary answer

Ethnicity influences ovarian reserve parameters and the outcome of ovarian stimulation for IVF / ICSI

What is known already

Infertility affects couples worldwide and due to a lack of a standardized reporting system, the real number, especially in developing countries, might be underestimated. The etiology of infertility may differ around the world and is often subjected not only to social, cultural and religious peculiarities, but also to different genetic influences. Published data suggest that ethnicity influences the ovarian reserve as well as the outcome of Assisted-Reproductive-Techniques (ART)-treatments. Key players of a successful ART outcome are the ovarian reserve and consequently the number of oocytes retrieved. Until today, the impact of ethnical differences is not sufficiently addressed in research.

Study design, size, duration

Prospective observational study, performed in 10 infertility centers worldwide (Europe (4 centers), Middle East North Africa (MENA) region (2 centers), Iran (2 centers), South America (1 center), India (1 center)) between May 2019 and September 2020, evaluating ovarian reserve and outcome parameters of ovarian stimulation treatments for IVF/ICSI. The study was approved by the Ethical Committee of each participating center.

Participants/materials, setting, methods

Couples with primary / secondary infertility and an indication for an IVF/ICSI treatment were included into this study. Besides anamnestic data regarding the history of the infertility and self-reported ethnicity (Arab, Caucasian, Hispanic, Ohters, Persian and South Asian), data obtained during the basic fertility assessment on the ovarian reserve parameters (Antral follicle count (AFC) and Anti-Muellerian-Hormone (AMH)) as well as stimulation parameters from the ovarian stimulation treatment were collected and analyzed.

Main results and the role of chance

This study comprised 1032 couples with the following distribution of the ethnicities: Arab 21.5%, Caucasian 15.9%, Hispanic 5%, Others 1.2%, Persian 33.4%, and South Asian 23%. The unadjusted means, SD and 95%CI (Confidence Interval) of AMH (ng/ml) for the groups were 3.33±0.19 [2.95–3.71]; 2.03±0.25 [1.55–2.52]; 2.43±0.74 [0.97–3.88]; 2.76±0.96 [0.88–4.64]; 3.10±0.16 [2.79–3.41]; 3.62±0.19 [3.25–3.98], for AFC 15.52±0.53 [14.49–16.55]; 12.00±0.67 [10.69–13.31]; 12.69±1.08 [10.57–14.81]; 15.11±2.60 [10.01–20.21]; 13.58±0.42 [12.75–14.41]; 13.49±0.51 [12.49–14.48] and for the number of retrieved oocytes (rCOC) 14.08±0.61 [12.88–15.27]; 9.84±0.71 [8.44–11.24]; 7.94±1.26 [5.48–10.41]; 9.92±2.62 [4.78–15.05]; 10.83±0.49 [9.87–11.79]; 17.06±0.59 [15.90–18.21], respectively. Univariate analysis of AMH, AFC and rCOC with the ethnicities revealed highly statistically significant differences for AMH and rCOC (p &lt; 0.001, respectively) and significant differences for AFC (p = 0.0014).

As age is a major confounder for the ovarian reserve, multivariate analyses were performed. After adjusting for age, AMH was significantly different between Arab-Persian, Arab-South Asian and Arab-Caucasian (p &lt; 0.001, p &lt; 0.001, p = 0.002) and AFC statistically significant between Arab and all other ethnicities. For rCOC, besides age, also the stimulation-dosage and -duration was taken into account. Highly statistically significant differences were found for the groups Arab-Persian and Arab-Caucasian and no differences towards the other ethnical groups.

Limitations, reasons for caution

Limitations of the study are an unequal number of included patients per ethnicity and that the data for the ovarian reserve parameters and the stimulation outcome were not available for all of the included patients.

Wider implications of the findings: Counselling of couples with infertility have to take, besides all other factors, also the ethnicity of the couple into account as ethnicity influences the ovarian reserve parameters as well as the number of retrieved oocytes in ovarian stimulation cycles for IVF/ICSI.

Trial registration number

ClinicalTrials.gov Identifier: NCT03927417

P–090 Cumulative live birth rates (CLBR) per embryo transfer, embryo transferred and inseminated oocyte are not affected by paternal age in infertile male donor egg cycles

Study question

Is reproductive success measured as CLBR per inseminated oocyte, per embryo transfer and per embryo transferred affected by paternal age in donor egg IVF-ICSI cycles?

Summary answer

Paternal age does not significantly affect reproductive outcomes measured by CLBR per inseminated oocyte, embryo transfer and embryo transferred in donor egg IVF-ICSI cyles.

What is known already

In recent years, the delay in the start of formation of a family has led to an increase of the average male age at which the first child is conceived. Therefore, there is a growing interest on the study of the impact of male age on the reproductive outcomes in assisted reproduction cycles (ART). Several studies have evaluated the effect of paternal age on reproductive outcomes using donor egg cycles to control for female factors. However, the results obtained on this topic are still controversial leading to a need of more research about it, which this study tries to address.

Study design, size, duration

This retrospective observational multicentric cohort study has included donor IVF-ICSI treatments (n = 1539) performed to couples with etiology of male infertility (non-normozoospermic) in Spain IVIRMA clinics between January 2008 and March 2020 using patients’ own sperm sample. Paternal age ranged from 28 to 74 years. The study population was categorized in 5 groups following the criterion of homogenizing the number of observations between groups 28–38 (A), 38–41 (B), 41–44 (C), 44–48 (D) y 48–74 (E) years.

Participants/materials, setting, methods

Considering that male age could be a factor affecting reproductive outcomes, we evaluated men with different age that performed a donor IVF-ICSI treatment with their own semen, etiology of male infertility and known age. Data was exported in order to obtain the clinical database and Kaplan-Meier was used for data analysis. P &lt; 0.05 was considered statistically significant. We measured reproductive success by CLBR per embryo transfer, per embryo transferred and per inseminated oocytes until live birth.

Main results and the role of chance

This study considered approximately 836 patients and 1411 embryo transfers. The CLBR per inseminated oocyte showed no significant difference between the study groups: A (3.09%, 42.61%, 71.96%), B (4.53%, 39.76%, 84.19%), C (5.89%, 47.04%, 78.61%), D (2.99%, 46.7%, 73.15%) and E (3.89%, 38.39%, 78.85%) for 7, 12 and 17 inseminated oocytes, respectively. In terms of CLBR per embryo transfer, the results obtained for each of the age groups were: A (51.55%, 70.69%, 92.18%), B (50.40%, 78.13%, 100.00%), C (53.68%, 71.69%, 100.00%), D (51.71%, 79.72%, 100.00%) and E (46.69%, 60.02%, 70.01%) for 3, 5 and 7 embryo transfers, respectively. No statistically significant differences were found among the studied age groups. CLBR per embryo transferred also did not show statistically significant differences between the age groups: A (8.43%, 53.34%, 72.13%), B (8.55%, 44,67%, 71.65%), C (10.40%, 53.94%, 72.49%), D (7.25%, 43.61%, 75.12%) and E (8.21%, 45.99%, 64.55%) for 1, 4 and 7 embryos transferred, respectively. Therefore, no significant differences were found in the number of inseminated oocytes, embryo transfers and embryos transferred needed to achieve a live birth between the age groups (p &gt; 0.05), suggesting that maybe paternal age has no relevant clinical effect on donor egg cycles with our categorization.

Limitations, reasons for caution

The retrospective nature of this study leads to biases derived from the clinical practice and to the presence of missing data (limiting sample size). Moreover, this study included donor egg cycles for controlling female factors, so this limits the generalization of our results to a population of young women.

Wider implications of the findings: Our study showed that the reproductive success measured as CLBR per embryo transfer, embryo transferred and inseminated oocytes was not statistically significant different among the studied age groups in donor egg cycles. Therefore, considering our study setting, paternal age does not affect reproductive success, however further studies should be done.

Trial registration number

NA

P–046 Application of hyperspectroscopy as a new sperm diagnostic and selection technique for ICSI based on hyperspectral signature of single spermatozoa – a proof of concept

Study question

Is hyperspectral imaging of individual sperm cells an appropriate candidate technique with potential to identify molecular characteristics of single spermatozoa prior to microinjection?

Summary answer

Preliminary tests have allowed us to obtain the images, set up the methodology and the correct segmentation of each sperm into its signature spectra.

What is known already

Although image techniques such as fluorescence microscopy and Raman spectroscopy have been used to identify biomarkers on sperm cells, their translation to the fertility clinic is highly complex and unfeasible. Hyperspectroscopy has not yet been introduced in the reproductive field, but it has been successfully used in other medical disciplines to differentiate cell types or pathological versus healthy tissue. It relies on the combination of information from optical images and electromagnetic spectra produced by cells at different wavelengths. Therefore, it is an interesting candidate for objective non-destructive sperm selection before ICSI according to the presence of specific biomarkers.

Study design, size, duration

Pilot, prospective, observational study in the IVIRMA Valencia fertility clinic, designed as a proof of concept. Discarded semen samples were used for the technical setup and the preliminary tests of image acquisition. Hyperspectral images were obtained of 12 spermatozoa: two sperm cells were imaged 10 times each, while the other 10 sperm were imaged one time each.

Participants/materials, setting, methods

Samples were prepared on glass-bottom ICSI plates in PVP droplets according to routine clinical practice. Images were obtained using the camera HinaLea 4200M coupled to the Olympus IX73 inverted microscope. Hypercubes were extracted using MATLAB 2016a, and the most informative wavelength was chosen. Matrox Copilot software was used to process images and select the regions of interest (ROI) equivalent to one sperm. MATLAB was used to obtain the information for the pixels within each ROI.

Main results and the role of chance

Hypercube size for each image was 608x968x299 pixels. Each hypercube obtained provided information for 299 different wavelengths, from 402.8 to 998.3 nm. Once the hypercubes were obtained from each image, the spectra at 520 nm wavelength was selected as the one at which the pixel provided the most information. The background of each uploaded image was successfully removed by creating a mask, which was then used to extract and characterize all the spectra from each pixel of each sperm image. The result of this proof of concept, though measure qualitatively, is that the information obtained from hyperspectral imaging of individual sperm is highly reproducible and successful in showing overlapping spectra resulting from 10 different images of the same specimen. Spectra resulting from images of different sperm cells showed tangible differences on their composition demonstrating unique biochemical features of each. The next step will be to quantitatively measure the reproducibility and sensitivity of the technique in a larger sample, to then study the potential of single sperm hyperspectral imaging as a sperm selection tool for ICSI.

Limitations, reasons for caution

These are preliminary results obtained from the development of an appropriate methodology to adapt the acquisition of hyperspectral images in the clinic’s IVF laboratory. Thus, the group will continue to evaluate the reproducibility, sensitivity, and informative capability of the technique before contemplating its use on samples destined to perform cycles.

Wider implications of the findings: Having developed a laboratory and image processing methodology that allows us to successfully segment each obtained image according to the hyperspectral information of every pixel of each individual sperm, we could move forward in testing the potential of these hyperspectral signatures to identify sperm markers related to successful reproductive outcomes.

Trial registration number

Not applicable

TESE-ICSI outcomes per couple in vasectomized males are negatively affected by time since the intervention, but not other comorbidities

RESEARCH QUESTION

Does time since vasectomy (as obstructive interval) and the presence of different male comorbidities adversely affect the likelihood of achieving a newborn for vasectomized males undergoing testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI)?

DESIGN

This retrospective study included 364 couples with vasectomized males undergoing TESE-ICSI cycles with autologous oocytes at IVI Valencia. The main outcome was live birth rate (LBR). Subjects were divided according to the male risk factor evaluated into quartiles (obstructive interval, body mass index [BMI]) or groups (hypertension, diabetes mellitus, dyslipidaemia). The reproductive outcomes were calculated per embryo transfer, per ovarian stimulation completed, and per couple.

RESULTS

The average obstructive interval was 11.3 years. The LBR was 34.4% (95% CI 30.1-38.6) per embryo transfer, 27.8% (95% CI 24.1-31.5) per ovarian stimulation and 46.2% (95% CI 41.8-51.3) per couple. When considering obstructive interval, a significantly lower LBR per couple (P = 0.04) was found in the group with the longest obstruction time: Q1 42.1% (95% CI 33.5-50.7), Q2 49.1% (95% CI 36.1-62.1), Q3 56.3% (95% CI 46.7-65.9) and Q4 37.2% (95% CI 26.5-47.9) but the cumulative live birth rate (CLBR) was not affected (P = 0.63). LBR per ovarian stimulation of males with hypertension was significantly lower (P = 0.04) than healthy males: 13.5% (95% CI 2.5-24.5) and 28.6% (95% CI 24.7-32.5), respectively. The group of diabetic vasectomized males had a significantly higher CLBR (P = 0.02). The remaining risk factors assessed (smoking, dyslipidaemia and a high BMI) did not affect LBR compared with their healthy counterparts.

CONCLUSION

Time since vasectomy appears to negatively influence the LBR when assessed per couple. The CLBR was not affected by the obstructive interval or the presence of other male comorbidities apart from diabetes, which had a significant effect.

Sperm Selection by Magnetic-Activated Cell Sorting before Microinjection of Autologous Oocytes Increases Cumulative Live Birth Rates with Limited Clinical Impact: A Retrospective Study in Unselected Males

Simple Summary

Many couples attending infertility clinics still need to repeat treatments and undergo several failed attempts before achieving a healthy newborn, which leaves room for improvement in the techniques we currently use in the clinic. Among the different procedures susceptible to improvement, the selection of the most adequate sperm to be injected inside the egg is crucial to the cycle’s success. Magnetic-activated cell sorting (MACS) is a technique that removes physiologically abnormal sperm that have started a programmed cell death (apoptotic) process from a semen sample. However, it is not recommended to all patients because there is no agreement between the published literature on whether it improves reproductive outcomes. This study used data from all intracytoplasmic sperm injection cycles performed using the patient’s own oocytes in our clinics from January 2008 to February 2020. Our findings support that MACS should not be recommended to all infertile couples, since there was no significant difference in results compared to treatments in which MACS was not used. This study provides clinicians and patients with more accurate information on how MACS will impact their chances of pregnancy, and it will lead to studies focused on specific populations to which the technique can be particularly helpful.

Abstract

The application of MACS non-apoptotic sperm selection in infertility clinics is controversial since the published literature does not agree on its effect on reproductive outcomes. Therefore, it is not part of the routine clinical practice. Classical measures of reproductive success (pregnancy or live birth rates per ovarian stimulation) introduce a bias in the evaluation of a technique’s effect, since only the best embryo is transferred. This retrospective, multicenter, observational study evaluated the impact of MACS on reproductive outcomes, measuring results in classical parameters and cumulative live birth rates (CLBR). Data from ICSI cycles using autologous oocyte in Spanish IVIRMA fertility clinics from January 2008 to February 2020 were divided into two groups according to their semen processing: standard practice (reference: 46,807 patients) versus an added MACS sperm selection (1779 patients). Only when measured as CLBR per embryo transferred and per MII oocyte used was the difference between groups statistically significant. There were no significant differences between MACS and reference groups on pregnancy and live birth rates. In conclusion, results suggest that non-apoptotic sperm selection by MACS on unselected males prior to ICSI with autologous oocytes has limited clinical impact, showing a subtle increase in CLBR per embryo transferred.

The RNA content of human sperm reflects prior events in spermatogenesis and potential post-fertilization effects

Transcriptome analyses using high-throughput methodologies allow a deeper understanding of biological functions in different cell types/tissues. The present study provides an RNA-seq profiling of human sperm mRNAs and lncRNAs (messenger and long non-coding RNAs) in a well-characterized population of fertile individuals. Sperm RNA was extracted from twelve ejaculate samples under strict quality controls. Poly(A)-transcripts were sequenced and aligned to the human genome. mRNAs and lncRNAs were classified according to their mean expression values (FPKM: Fragments Per Kilobase of transcript per Million mapped reads) and integrity. Gene Ontology analysis of the Expressed and Highly Expressed mRNAs showed an involvement in diverse reproduction processes, while the Ubiquitously Expressed and Highly Stable mRNAs were mainly involved in spermatogenesis. Transcription factor enrichment analyses revealed that the Highly Expressed and Ubiquitously Expressed sperm mRNAs were primarily regulated by zinc-fingers and spermatogenesis-related proteins. Regarding the Expressed lncRNAs, only one-third of their potential targets corresponded to Expressed mRNAs and were enriched in cell-cycle regulation processes. The remaining two-thirds were absent in sperm and were enriched in embryogenesis-related processes. A significant amount of post-testicular sperm mRNAs and lncRNAs was also detected. Even though our study is solely directed to the poly-A fraction of sperm transcripts, results indicate that both sperm mRNAs and lncRNAs constitute a footprint of previous spermatogenesis events and are configured to affect the first stages of embryo development.

Effect and in silico characterization of genetic variants associated with severe spermatogenic disorders in a large Iberian cohort

BACKGROUND

Severe spermatogenic failure (SpF) represents the most extreme manifestation of male infertility, as it decreases drastically the semen quality leading to either severe oligospermia (SO, <5 million spermatozoa/mL semen) or non-obstructive azoospermia (NOA, complete lack of spermatozoa in the ejaculate without obstructive causes).

OBJECTIVES

The main objective of the present study is to analyze in the Iberian population the effect of 6 single-nucleotide polymorphisms (SNPs) previously associated with NOA in Han Chinese through genome-wide association studies (GWAS) and to establish their possible functional relevance in the development of specific SpF patterns.

MATERIALS AND METHODS

We genotyped 674 Iberian infertile men (including 480 NOA and 194 SO patients) and 1058 matched unaffected controls for the GWAS-associated variants PRMT6-rs12097821, PEX10-rs2477686, CDC42BPA-rs3000811, IL17A-rs13206743, ABLIM1-rs7099208, and SOX5-rs10842262. Their association with SpF, SO, NOA, and different NOA phenotypes was evaluated by logistic regression models, and their functional relevance was defined by comprehensive interrogation of public resources.

RESULTS

ABLIM1-rs7099208 was associated with SpF under both additive (OR = 0.86, p = 0.036) and dominant models (OR = 0.78, p = 0.026). The CDC42BPA-rs3000811 minor allele frequency was significantly increased in the subgroup of NOA patients showing maturation arrest (MA) of germ cells compared to the remaining NOA cases under the recessive model (OR = 4.45, p = 0.044). The PEX10-rs2477686 SNP was associated with a negative testicular sperm extraction (TESE) outcome under the additive model (OR = 1.32, p = 0.034). The analysis of functional annotations suggested that these variants affect the testis-specific expression of nearby genes and that lincRNA may play a role in SpF.

CONCLUSIONS

Our data support the association of three previously reported NOA risk variants in Asians (ABLIM1-rs7099208, CDC42BPA-rs3000811, and PEX10-rs2477686) with different manifestations of SpF in Iberians of European descent, likely by influencing gene expression and lincRNA deregulation.

Minimal ovarian stimulation is an alternative to conventional protocols for older women according to Poseidon's stratification: a retrospective multicenter cohort study

OBJECTIVE

To investigate whether minimal ovarian stimulation (mOS) is as effective as conventional ovarian stimulation (cOS) for older women belonging to different groups according to the Poseidon criteria.

MATERIAL AND METHODS

Observational retrospective multicentre cohort including women from Poseidon's groups 2 and 4 that underwent in vitro fertilization (IVF). We performed a mixed-effects logistic regression model, adding as a random effect the patients and the stimulation cycle considering the dependence of data. Survival curves were employed as a measure of the cumulative live birth rate (CLBR). The primary outcomes were live birth rate per embryo transfer and CLBR per consecutive embryo transfer and oocyte consumed until a live birth was achieved.

RESULTS

A total of 2002 patients underwent 3056 embryo transfers (mOS = 497 and cOS = 2559). The live birth rates per embryo transfer in mOS and cOS showed no significant difference in both Poseidon's groups. Likewise, the logistic regression showed similar live birth rates between the two protocols in Poseidon's groups 2 (OR 1.165, 95% CI 0.77-1.77; p = 0.710) and 4 (OR 1.264 95% CI 0.59-2.70; p = 0.387). However, the survival curves showed higher CLBR per oocyte in women that received mOS (Poseidon group 2: p < 0.001 and Poseidon group 4: p = 0.039).

CONCLUSIONS

Minimal ovarian stimulation is a good alternative to COS as a first-line treatment for patients belonging to Poseidon's groups 2 and 4. The number of oocytes needed to achieve a live birth seems inferior in mOS strategy than cOS.