The Impact of Coronavirus Disease 2019 Pandemic on Female Patients Seeking or Undergoing Fertility Treatment in a Single In vitro Fertilisation Clinic in Greece: An International, Cross-sectional Study

Background

The temporary delay in fertility treatments due to the coronavirus disease 2019 (COVID-19) pandemic, in combination with the imposed lockdowns, has created psychological distress and anxiety amongst infertile patients.

Aims

The aim of this study was to evaluate how the pandemic has influenced assisted reproduction technology (ART) patients in Greece, during the second wave of the pandemic. An additional aim was to examine the effects of the pandemic on cross-border patients in particular, compared to national ones.

Settings and Design

This study was a cross-sectional, questionnaire-based study, distributed to 409 patients of a single in vitro fertilisation (IVF) clinic in Greece, during the period between January until the end of April 2021.

Materials and Methods

The survey was conducted online via E-mail and was distributed to national and international female patients of a single IVF clinic in Greece, who were undergoing ART treatment during the second wave of the COVID-19 pandemic. Patient participation was anonymous, and participants provided informed consent for collection and publication of data.

Statistical Analysis Used

The mean values of baseline characteristics, along with answer percentages per questionnaire item, were calculated. Collected data were cross-tabulated, and the Chi-square test was used as a measurement of the differences between national and cross-border patients. A P value lower than 0.05 was considered statistically significant. All analyses were conducted using the SPSS Statistics software.

Results

From 409 initial candidates, 106 women, with a mean age of 41.2 years, completed the questionnaire (26% response rate). The majority of national patients did not experience any delays in their fertility plans (62%), while cross-border patients experienced over 6 months of delays (54.7%). The main reason for fertility postponement was travel restrictions due to COVID-19 for cross-border patients (62.5%), while national patients cited additional reasons. The majority of patients experienced a degree of stress (65.2%) due to the delays, however were not fearful of COVID-19 infection (54.7%). Most patients were aware of the protective measures taken by IVF clinics (80.2%), and this was a determinant factor (71.7%) for their decision to restart their fertility treatment.

Conclusion

The COVID-19 pandemic lockdowns had a significant emotional impact on patient receiving or undergoing ART treatment in Greece. This impact was more pronounced on cross-border patients. This highlights the need for continuation of ART care, with the appropriate protective measures, during the pandemic, as well as during similar times of crisis in the future.

Generation of surrogate goldfish Carassius auratus progeny from common carp Cyprinus carpio parents

Surrogate broodstock technology can increase the production efficiency of commercially important fishes that are difficult to breed in confinement and aid the propagation and recovery of endangered populations. In this study, we report the application of germ cell (GC) transplantation (GCT) for increasing the numbers of progeny produced by small-bodied ornamental fishes by using sexually mature adult fish as recipients. The GCs isolated from prepubertal male goldfish (Carassius auratus) donors (n = 5) were transplanted through the genital papilla into the gonads of adult common carp (Cyprinus carpio) recipients. The endogenous GCs of the recipient were depleted using busulfan (40 mg/kg body weight [BW]; in five doses at 2-week intervals) and high-temperature (38 °C) treatments. Within 4 months after GCT, the donor GCs recolonised the recipients' gonads and resumed gametogenesis. The presence of donor-derived gametes was confirmed through polymerase chain reaction-restriction fragment length polymorphism analysis in all the surrogate common carp males and females. Artificial fertilisation and induced spawning between surrogate males and females yielded pure goldfish progeny; the fertilisation and hatching rates were similar to those of the controls. These results suggest that GCT could also be potentially applied in commercial aquaculture, mainly to increase the numbers of progeny obtained from small-bodied fishes those having low gamete counts.

Artificial Insemination in Axolotl

In axolotls (Ambystoma mexicanum), fertilization takes place internally. After courtship, the male axolotl deposits spermatophores, which the female takes up into her cloaca in order to fertilize eggs internally. The success of axolotl breedings is subject to several poorly understood factors including age, pairing, and genotype. In some cases, individuals are unable to breed naturally despite having significant scientific value. Assisted reproductive technologies represent one approach to maintaining stocks of such individuals, as well as supplementing natural breedings of laboratory stocks.Here, we describe a protocol for artificial insemination--an assisted reproductive technology in which sperm is extracted from a male and transferred into the female cloaca, thus mimicking natural fertilization in axolotls. We believe that this simple method can be applied to other salamander species that have internal fertilization and also help restore endangered wild populations.

Projecting the Contribution of Assisted Reproductive Technology to Completed Cohort Fertility

Assisted reproductive technology (ART) is increasingly influencing the fertility trends of high-income countries characterized by a pattern of delayed childbearing. However, research on the impact of ART on completed fertility is limited and the extent to which delayed births are realized later in life through ART is not well understood. This study uses data from Australian fertility clinics and national birth registries to project the contribution of ART for cohorts of women that have not yet completed their reproductive life and estimate the role played by ART in the fertility 'recuperation' process. Assuming that the increasing trends in ART success rates and treatment rates continue, the projection shows that the contribution of ART-conceived births to completed fertility will increase from 2.1% among women born in 1968 to 5.7% among women born in 1986. ART is projected to substantially affect the extent to which childbearing delay will be compensated at older ages, suggesting that its availability may become an important factor in helping women to achieve their reproductive plans later in life.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11113-023-09765-3.

A dual-center study of predictive factors for sperm retrieval through microdissection testicular sperm extraction and intracytoplasmic sperm injection outcomes in men with non-mosaic Klinefelter syndrome

PURPOSE

This study evaluated the predictors of sperm retrieval (SR) in non-mosaic Klinefelter syndrome (KS) patients undergoing microsurgical testicular sperm extraction (mTESE). The cutoff values of the predictors of SR and overall pregnancy rates after intracytoplasmic sperm injection (ICSI) were analyzed for the positive SR (PSR) cases.

MATERIALS AND METHODS

The study was a dual-center retrospective study. Overall 118 patients with KS underwent mTESE between January 2011 and July 2021. Clinicopathological factors including comorbidities, endocrine profiles, and testicular volumes were analyzed.

RESULTS

A total of 58 patients showed PSR (49.2%) and 60 patients (50.8%) had negative SR (NSR). The mean overall age of the patients was 32.5 years. The NSR patients had a significantly greater prevalence of obesity, diabetes mellitus, and cerebrovascular disease. The PSR group had a significantly higher left testis mean volume (p=0.039). The differences between the two study groups regarding follicular-stimulating hormone, luteinizing hormone, and testosterone variations at 1 and 3 months after mTESE were insignificant. Preoperative mean neutrophil-to-lymphocyte ratio was significantly greater in the NSR group (p=0.011), but the platelet-to-lymphocyte ratio showed no significant difference between the two study groups. A live child birth was achieved in 53.4% of the PSR patients. Multivariate logistic analysis showed that total testicular volume >3.93 mL, left testis volume >1.79 mL, and neutrophil-to-lymphocyte ratio ≤1.82 were significantly associated with PSR.

CONCLUSIONS

mTESE-ICSI is a feasible method for KS patients to have a child, and total testicular volume, left testis volume, and neutrophil-to-lymphocyte ratio might be predictors of successful SR.

Comparison of clinical effects between early follicular prolonged GnRH agonist protocol and GnRH antagonist protocol in 3310 cycles: a retrospective study

BACKGROUND

It is the duty of doctors to choose a safe, simple, economic and effective controlled ovulation stimulation (COS) protocol for the patients. This study aims to compare the clinical effects of the early follicular prolonged GnRH agonist (EFPL) and GnRH antagonist (GnRH-Ant) protocols, hoping to provide some reference for clinicians when choosing COS program.

METHODS

A retrospective study included 3310 ovum pick up cycles undergoing assisted reproductive technology during January 2019 to May 2022 in Renmin Hospital of Wuhan University. Propensity Score Matching (PSM) and multivariable logistic regression analysis were used to improve the comparability between the two protocols. Subgroups were divided according to age, body mass index (BMI) and anti-Mullerian hormone (AMH). The live birth rate (LBR) and clinical pregnancy rate (CPR) were the primary outcomes.

RESULTS

After PSM, the endometrial thickness, fresh embryo transplantation rate, chemical pregnancy rate, CPR were significantly higher in EFPL group than that in GnRH-Ant group (P < 0.001). The E2, LH, P values on trigger day were significantly lower in EFPL group (P < 0.001). The cycle cancellation rate was significantly reduced in EFPL group (P < 0.001). However, the total amount of Gn and duration of Gn were significantly increased in the EFPL group (P < 0.001). Multivariable logistic regression analysis showed that the LBR was significantly higher in EFPL group after matching [OR (95%CI), 1.86 (1.13, 3.05), P = 0.02], especially for those with age < 35 years [OR (95%CI), 1.95 (1.14, 3.34), P = 0.02], BMI < 24 kg/m² [OR (95%CI), 2.08 (1.14, 3.80), P = 0.02], AMH levels ≥ 4.5 ng/ml [OR (95%CI), 4.19 (1.53, 11.43), P < 0.01].

CONCLUSION

EFPL regimen is more suitable to elicit live birth for those young patients with BMI < 24 kg/m² and AMH ≥ 4.5 ng/ml. However, for patients with decreased ovarian reserve or advanced age, EFPL regimen has no advantage over the GnRH-Ant regimen.

Chromosomal analysis of 262 miscarried conceptuses: a retrospective study

BACKGROUND

Embryonic chromosomal abnormality is one of the significant causative factors of pregnancy loss. Our goal was to investigate the differences of chromosomal abnormality between different conception modes in miscarried products of conception (POCs).

METHODS

A retrospective study included 262 miscarried POCs from 167 women undergoing assisted reproductive treatment (ART) and 95 spontaneous pregnant (SP) women during March 2019 to March 2022 in Renmin Hospital of Wuhan University. Subgroups were divided according to age, fertilization method, types and stages of embryo transfer. The profiles of cytogenetic abnormalities in the miscarried POCs were measured via next-generation sequencing.

RESULTS

The rate of chromosomal abnormality in the fresh embryo transfer group and the cleavage embryo transfer group was significantly higher than that in the frozen embryo transfer group (79.2% vs. 36%, P = 0.0001) and the blastocyst transfer group (66.7% vs. 32.1%, P = 0.0001) respectively. There was no significant difference in the rate of chromosomal abnormalities when compared by maternal age (49.2% vs. 62%, P = 0.066), types of conception (49.7% vs. 57.9%, P = 0.202), fertilization method (49.6% vs. 48.7%, P = 0.927) and frequency of abortion (56% vs. 47.6%, P = 0.183). However, the women aged ≥ 35 years had more frequent numerical abnormality (P = 0.002); patients using assisted reproductive technology had more rate of chromosomal structural abnormalities (26.5% vs. 7.3%, P = 0.005); the ICSI fertilization group has more frequency of deletion/microdeletion than the IVF fertilization group (80% vs. 31.3%, P = 0.019).

CONCLUSION

Blastocyst transfer might help to reduce the incidence of miscarriage. In addition, "freezing all" should be considered if encountered hyper ovarian stimulation, to avoid the negative effect of high estrogen environment on embryo development. The higher incidence of structural abnormalities in miscarried POCs from assisted reproductive patients reminds us to pay attention to the safety of the technology for offspring.

Comparison of oocyte vitrification using a semi-automated or a manual closed system in human siblings: survival and transcriptomic analyses

BACKGROUND

Indications of oocyte vitrification increased substantially over the last decades for clinical and ethical reasons. A semi-automated vitrification system was recently developed making each act of vitrification reproducible. In this study, we evaluated the efficiency of the semi-automated technique of oocyte vitrification by survival rate, morphometric assessment and resistance to empty micro-injection gesture as compared with a manual method. Additionally, we intended to evaluate transcriptomic consequences of both techniques using single-cell RNA-seq technology.

RESULTS

Post-warming survival rate, oocyte surfaces and resistance to empty micro-injection were comparable between semi-automated and manual vitrification groups. Both oocyte vitrification techniques showed limited differences in the resulting transcriptomic profile of sibling oocytes since only 5 differentially expressed genes were identified. Additionally, there was no difference in median transcript integrity number or percentage of mitochondrial DNA between the two groups. However, a total of 108 genes were differentially expressed between fresh and vitrified oocytes (FDR < 0.05) and showed over-represented of genes related to important cellular process.

CONCLUSIONS

Our results provide reassurance about the influence of semi-automation as compared with the manual vitrification method. Concerning oocyte vitrification itself, no tight common transcriptomic signature associated has been observed across studies.

TRIAL REGISTRATION

NCT03570073.

Hemoperitoneum complicating an oocyte puncture in a chronic hemodialysis patient

We report the case of a 31-year-old patient on chronic hemodialysis for 17 years, after two failed kidney grafts, presently on daily home hemodialysis. She underwent follicle puncture for oocyte retrieval in the context of an in vitro fertilization program. This procedure was complicated by hemoperitoneum, requiring transfusion of 2 units of packed red blood cells and 2 units of fresh-frozen plasma, as well as an emergency laparoscopy to drain the hemoperitoneum and perform local hemostasis of the ovarian bleeding. This complication occurred following the patient's routine hemodialysis session, performed with the usual systemic anticoagulation with unfractionated heparin. The evolution was favorable and there was no recurrence of bleeding or sequelae. A later hematology workup did not reveal any pathology of hemostasis that might have favored bleeding. This case may underline how, even though assisted reproductive procedures are increasingly performed in patients on dialysis, special care should be taken when these procedures are performed in this fragile population.

Quantitative approaches in clinical reproductive endocrinology

Understanding the human hypothalamic-pituitary-gonadal (HPG) axis presents a major challenge for medical science. Dysregulation of the HPG axis is linked to infertility and a thorough understanding of its dynamic behaviour is necessary to both aid diagnosis and to identify the most appropriate hormonal interventions. Here, we review how quantitative models are being used in the context of clinical reproductive endocrinology to: 1. analyse the secretory patterns of reproductive hormones; 2. evaluate the effect of drugs in fertility treatment; 3. aid in the personalization of assisted reproductive technology (ART). In this review, we demonstrate that quantitative models are indispensable tools enabling us to describe the complex dynamic behaviour of the reproductive axis, refine the treatment of fertility disorders, and predict clinical intervention outcomes.

POSEIDON groups and their distinct reproductive outcomes: Effectiveness and cost-effectiveness insights from real-world data research

The Patient-Oriented Strategies Encompassing IndividualizeDOocyte Number (POSEIDON) criteria identify and classify the so-called 'low-prognosis' patients undergoing assisted reproductive technology (ART). Recent large-scale studies using real-world data (RWD) have shown that patients classified under this system have distinct reproductive outcomes. Moreover, these studies also confirm that POSEIDON patients are commonly found in fertility centers. RWD has substantiated the validity of the POSEIDON biomarkers' thresholds (antral follicle count [AFC] and/or anti-Müllerian hormone [AMH]) for patient classification. Lastly, a predictive model has been developed and validated to estimate the POSEIDON metric of success (i.e., number of oocytes needed to achieve at least one euploid blastocyst). Although more evidence is needed in this area, current insights from RWD research indicate that infertility patients can be counseled and managed more effectively under the POSEIDON scope, with potential gains for all parties involved.

Associations of maternal obesity, frozen embryos, and offspring adverse cardiometabolic alterations

OBJECTIVE

To evaluate the long-term cardiometabolic health of offspring conceived by frozen embryo transfer and born to mothers with overweight/obesity.

DESIGN

Retrospective cohort study.

SETTING

Center for Reproductive Medicine.

PATIENT(S)

A total of 2,741 offspring born to mothers who underwent in vitro fertilization/intracytoplasmic sperm injection treatment were followed between June 2014 and August 2021. The offspring were singletons aged 4-11 years at follow-up.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Age-specific z-scores of cardiometabolic parameters were examined, including adiposity, systolic/diastolic blood pressure, glucose, and lipid profiles, and the metabolic sum score of different cardiometabolic characteristics.

RESULTS

Of 2,741 offsprings, 965 (35.21%) were born to mothers with overweight/obesity, including 396 (41.04%) offspring who were conceived by frozen embryo transfer. After adjusting for paternal and maternal age, paternal body mass index (BMI), offspring age, offspring sex, and offspring postnatal energy intake, offspring born to mothers with overweight/obesity and conceived by frozen embryo transfer showed a significantly higher BMI z-score, systolic blood pressure z-score, metabolic sum score-1, and metabolic sum score-2 compared with those conceived by fresh embryo transfer (BMI z-score: adjusted mean difference, 0.17; 95% confidence interval [CI], 0.04-0.30; systolic blood pressure z-score: adjusted mean difference, 0.16; 95% CI, 0.02-0.29; metabolic sum score-1: adjusted mean difference, 0.54; 95% CI, 0.15-0.94; metabolic sum score-2: adjusted mean difference, 0.45; 95% CI, 0.07-0.83). However, in offspring of mothers with normal weight, offspring conceived by frozen embryo transfer showed a significantly lower low-density lipoprotein-cholesterol z-score compared with those conceived by fresh embryo transfer (adjusted mean difference, -0.12; 95% CI, -0.22 to -0.02). Other cardiometabolic parameters were comparable between offspring with frozen and fresh embryo transfers after adjusting for multivariate confounder variables.

CONCLUSIONS

This study found that among offspring from mothers who were overweight/obese, those offspring conceived by frozen embryo transfer were associated with higher systolic blood pressure z-scores and adverse metabolic changes compared with those conceived by fresh embryo transfer. The changes show that the association between frozen embryo transfer and offspring adverse cardiometabolic changes is apparent only among those born to mothers who are overweight/obese.

Validation of a SARS-CoV-2 RT-PCR assay: a requirement to evaluate viral contamination in human semen

RESEARCH QUESTION

Is it possible to validate an accurate and reliable method for direct detection of SARS-CoV-2 by reverse transcription polymerase chain reaction (RT-PCR) in human semen fractions?

DESIGN

This qualitative improvement study aimed to provide a prospective validation of SARS-CoV-2 detection in male semen. The SARS-CoV-2 genome was detected by multiplex real-time RT-PCR on patient samples that underwent routine semen analyses for infertility at the Center for Reproductive Medicine at the University Hospital of Clermont-Ferrand. Samples comprised surplus semen collected for treatment with assisted reproductive technology. Seminal fluid and spermatozoa fractions were isolated with density gradient centrifugation and cryopreserved. Positive samples were prepared with a standard of inactivated SARS-CoV-2 particles.

RESULTS

The analytical method was validated in both seminal fluid and spermatozoa fractions. In both semen fractions, the assay was repeatable, reproducible and showed high sensitivity with a limit of detection of 0.33 SARS-CoV-2 genome copies/µl. The limit of quantification was 1 copy of the SARS-CoV-2 genome/µl. The method was effective regardless of semen quality (normal and altered sperm parameters), number of spermatozoa or the cryoprotectant media used to freeze spermatozoa.

CONCLUSION

This validated RT-PCR assay provided accurate and reliable screening of SARS-CoV-2 in seminal fluid and spermatozoa fractions. This method is essential to ensure protection against viral contamination in the cryobanking process.

Non-invasive evaluation of embryo quality for the selection of transferable embryos in human in vitro fertilization-embryo transfer

The ultimate goal of human assisted reproductive technology is to achieve a healthy pregnancy and birth, ideally from the selection and transfer of a single competent embryo. Recently, techniques for efficiently evaluating the state and quality of preimplantation embryos using time-lapse imaging systems have been applied. Artificial intelligence programs based on deep learning technology and big data analysis of time-lapse monitoring system during in vitro culture of preimplantation embryos have also been rapidly developed. In addition, several molecular markers of the secretome have been successfully analyzed in spent embryo culture media, which could easily be obtained during in vitro embryo culture. It is also possible to analyze small amounts of cell-free nucleic acids, mitochondrial nucleic acids, miRNA, and long non-coding RNA derived from embryos using real-time polymerase chain reaction (PCR) or digital PCR, as well as next-generation sequencing. Various efforts are being made to use non-invasive evaluation of embryo quality (NiEEQ) to select the embryo with the best developmental competence. However, each NiEEQ method has some limitations that should be evaluated case by case. Therefore, an integrated analysis strategy fusing several NiEEQ methods should be urgently developed and confirmed by proper clinical trials.

An explainable deep learning-based algorithm with an attention mechanism for predicting the live birth potential of mouse embryos

In assisted reproductive technology (ART), embryos produced by in vitro fertilization (IVF) are graded according to their live birth potential, and high-grade embryos are preferentially transplanted. However, rates of live birth following clinical ART remain low worldwide. Grading is based on the embryo shape at a limited number of stages and does not consider the shape of embryos and intracellular structures, e.g., nuclei, at various stages important for normal embryogenesis. Here, we developed a Normalized Multi-View Attention Network (NVAN) that directly predicts live birth potential from the nuclear structure in live-cell fluorescence images of mouse embryos from zygote to across a wide range of stages. The input is morphological features of cell nuclei, which were extracted as multivariate time-series data by using the segmentation algorithm for mouse embryos. The classification accuracy of our method (83.87%) greatly exceeded that of existing machine-learning methods and that of visual inspection by embryo culture specialists. Our method also has a new attention mechanism that allows us to determine which values of multivariate time-series data, used to describe nuclear morphology, were the basis for the prediction. By visualizing the features that contributed most to the prediction of live birth potential, we found that the size and shape of the nucleus at the morula stage and at the time of cell division were important for live birth prediction. We anticipate that our method will help ART and developmental engineering as a new basic technology for IVF embryo selection.

Use of a recombinant human follicle-stimulating hormone:recombinant human luteinizing hormone (r-hFSH:r-hLH) 2:1 combination for controlled ovarian stimulation during assisted reproductive technology treatment: A real-world study of routine practice in the Russian Federation

Two observational studies in the Russian Federation described patient demographics/clinical decision for treatment with recombinant human follicle-stimulating hormone:recombinant human luteinizing hormone (r-hFSH:r-hLH) 2:1 combination for ovarian stimulation (OS) during assisted reproductive technology (ART) and outcomes, respectively. The first (prospective) study enrolled 500 patients. After post-hoc regrouping to assign patients to discrete groups, 378 (75.6%) met the local Russian label for an r-hFSH:r-hLH 2:1 combination, 105 (21%) were treated according to other physician preference, and 17 (3.4%) met only the ESHRE Bologna criteria for a poor ovarian response. The clinical pregnancy rate per cycle was 30.4%. A total of 158/175 (90.3%) women achieving clinical pregnancy in the prospective study participated in the second (retrospective) study. The live birth rate per cycle was 25.8%. No new safety concerns were reported. These results support the use of the r-hFSH:r-hLH 2:1 combination in patients with a poor/suboptimal response to OS for ART treatment in the Russian Federation.

An examination of mediation by DNA methylation on birthweight differences induced by assisted reproductive technologies

BACKGROUND

Children born after assisted reproductive technologies (ART) differ in birthweight from those naturally conceived. It has been hypothesized that this might be explained by epigenetic mechanisms. We examined whether cord blood DNA methylation mediated the birthweight difference between 890 newborns conceived by ART (764 by fresh embryo transfer and 126 frozen thawed embryo transfer) and 983 naturally conceived newborns from the Norwegian Mother, Father, and Child Cohort Study (MoBa). DNA methylation was measured by the Illumina Infinium MethylationEPIC array. We conducted mediation analyses to assess whether differentially methylated CpGs mediated the differences in birthweight observed between: (1) fresh embryo transfer and natural conception and (2) frozen and fresh embryo transfer.

RESULTS

We observed a difference in birthweight between fresh embryo transfer and naturally conceived offspring of - 120 g. 44% (95% confidence interval [CI] 26% to 81%) of this difference in birthweight between fresh embryo transfer and naturally conceived offspring was explained by differences in methylation levels at four CpGs near LOXL1, CDH20, and DRC1. DNA methylation differences at two CpGs near PTGS1 and RASGRP4 jointly mediated 22% (95% CI 8.1% to 50.3%) of the birthweight differences between fresh and frozen embryo transfer.

CONCLUSION

Our findings suggest that DNA methylation is an important mechanism in explaining birthweight differences according to the mode of conception. Further research should examine how gene regulation at these loci influences fetal growth.

Comparison of frozen-thawed embryo transfer strategies for the treatment of infertility in young women: a retrospective study

Objective

To investigate transfer strategies in the frozen-thawed embryo transfer (FET) cycle.

Methods

The clinical data of 1,652 FET patients were divided into five groups according to the number and quality of the transferred blastocyst: high-quality single blastocyst group (group A, n = 558), high-quality plus poor-quality double blastocyst group (group B, n = 435), poor-quality double blastocyst group (group C, n = 241), high-quality double blastocyst group (group D, n = 298), and poor-quality single blastocyst group (group E, n = 120). Inter-group comparison analyses of primary conditions, pregnancy outcomes and neonatal outcomes were then performed.

Results

Group A had the highest embryo implantation rate (67.38%), significantly different from the implantation rates of the other four groups. The gemellary pregnancy rate (1.60%), preterm birth rate (5.58%), neonatal birth weight (3,350g [3,000g, 3,650g]), neonatal birth age (39.57 weeks [38.71, 40.34]), and incidence of low birth weight (7.02%) in group A were different from those in groups B, C, and D, but did not significantly differ from those in group E. Moreover, the proportions of male infants born in groups A (56.86%) and D (59.41%) were significantly higher than those in the other three groups. Double blastocyst transfer (0.528, 95% CI [0.410-0.680], P < 0.001) and high-quality blastocyst transfer (0.609, 95% CI [0.453-0.820], P = 0.001) were found to be protective factors for live birth. In addition, double blastocyst transfer was also the largest risk factor for pregnancy complications (3.120, 95% CI [2.323-4.190], P < 0.001) and neonatal complications (2.230, 95% CI [1.515-3.280], P < 0.001), especially for gemellary pregnancy (59.933, 95% CI [27.298-131.58], P < 0.001) and preterm birth (3.840, 95% CI [2.272-6.489], P < 0.001). Based on the ROC curves, a double blastocyst transfer could predict gemellary pregnancy reliably with a high area under the curve (AUC = 78.53%). Additionally, a double blastocyst transfer could effectively predict a high risk of pregnancy complications (AUC = 65.90%), neonatal complications (AUC = 64.80%) and preterm birth (AUC = 66.20%).

Conclusion

The live birth rate of frozen-thawed high-quality single blastocyst transfer is lower than that of double high-quality blastocyst transfer, which can significantly increase the embryo implantation rate. High-quality single blastocyst transfer also significantly lowers the risk of gemellary pregnancy, preterm birth, and low birth weight, and can significantly improve maternal and infant outcomes. After weighing the pros and cons of live birth with pregnancy and neonatal complications, the authors believe that high-quality single blastocyst transfer is the optimal FET strategy for young women and is worthy of further clinical application. Despite this recommendation, high-quality single blastocyst transfer can increase the risk of monozygotic twins, as well as significantly increase the proportion of male infants born.

Functional substitution of zona pellucida with modified sodium hyaluronate gel in human embryos

PURPOSE

Zona pellucida-free (ZP-free) embryos often fail to achieve good developmental outcomes and are routinely discarded in assisted reproductive laboratories. Existing attempts to rescue ZP-free embryos are not widely used due to operational complexity and high technical requirements. To handle cases with missing ZP, we applied modified sodium hyaluronate gel (MSHG) to embryo culture to determine if it can function as a substitute for human zona pellucida.

METHODS

The developmental process and the blastocyst formation rate of embryos were analyzed in both mouse and human. The first clinical application of MSHG was reported, and the pregnancy outcome was continuously followed up.

RESULTS

Human and mouse ZP-free embryos cultured with MSHG showed a blastocyst formation rate similar to ZP-intact embryos. MSHG improves blastocysts formation rate by maintaining blastomere spatial arrangement at early stages. Compared to ZP-free embryos, the proportion of tetrahedrally arranged blastomeres at the 4-cell stage increased significantly in embryos cultured with MSHG in humans. A ZP-free blastocyst cultured in MSHG with the highest score was successfully implanted after day 5 transplantation and developed normally.

CONCLUSION

These data demonstrate that MSHG can substitute the function of zona pellucida and rescue human ZP-free embryos during assisted reproductive technology.

Assisted Reproductive Technology and Natural Law: How Seven Years as an Embryologist Revealed IVF's Disordered Approach to Patient Care

This article is a case study illuminating the experience of a cradle Catholic who pursued a career in the field of Assisted Reproductive Technology (ART) as a laboratory director and embryologist. Twenty years after leaving the field, the observations leading to the crisis of conscience are further amplified by the reports of social, legal, ethical, and medical consequences of the technology. These consequences are explored in detail and can serve as a mini-review of the published scientific literature describing the obstetrical complications, peri-natal outcomes, and the long-term health effects on the offspring. This paper provides the documented evidence that can be used by the religious and medical community for shepherding the flock. The disordered approach to patient care is evidenced by five serious consequences resulting from the use of the technology. These include multiple pregnancy and selective reduction, abandoned and discarded embryos, adverse health effects to the women and children, legal and ethical problems, and human experimentation. An explanation for the adverse consequences can be found by exploring and applying the principles of Natural Law. Natural Law, as embraced by the Catholic Church, can be used as a starting point for conversion of heart for many who struggle with the immorality of ART. Deterring use of the technology coupled with increased motivation by scientist and health professionals to pursue restorative approaches within a moral framework offer our best solution to the treatment of infertility. Natural Law and the consequences of violating it provide evidence that science and medicine should not be practiced in a vacuum void of ethical and moral boundaries grounded in divine Wisdom.

Embryo transfer-the who, what, when, how, and why does it matter?

Embryo transfer is the ultimate step in the in vitro fertilization process and is the culmination of months to years of preparation. Many factors contribute to embryo transfer success before, during, and after the transfer. This series is a comprehensive review of the factors that converge to influence embryo transfer success. Robust discussion is included regarding the impact of the physician who performs the transfer, adjunct therapies used, timing of embryo transfer, endometrial receptivity, and resultant health of the pregnancy and offspring.

Does Testicular Sperm Alter Reproductive and Perinatal Outcomes in Assisted Reproductive Technology Cycles? 10 Years' Experience in an Indian Clinic

Background

Intra-Cytoplasmic Sperm Injection (ICSI) has revolutionized the reproductive outcomes for couples with male factor infertility. Especially in azoospermic men, use of ICSI with surgically retrieved testicular sperm has helped them have their own biological child. However, considering the immature nature of testicular sperm safety of testicular sperm has been debated.

Aims

To compare reproductive outcomes, neonatal outcomes and the incidence of congenital malformations in children born after intracytoplasmic sperm injection (ICSI), using different sperm origins.

Settings and Design

This is a retrospective study in which a total of 989 participants were enrolled. Study group (Testicular Sperm Aspiration (TESA) ICSI group) had 552 couples with female partners aged ≤37 and had self gamete cycles. ICSI cycles with ejaculated sperm (EJS) acted as the control group.

Materials and Methods

All male patients underwent surgical sperm retrieval and all the women underwent controlled ovarian stimulation and transvaginal oocyte retrieval and Ovum Pick Up (OPU) as per the standard operating procedures of the clinic. Frozen embryo transfer with two good-grade blastocysts, which had shown 100% survival, were transferred in subsequent cycles.

Statistical Analysis Used

The Student's t-test was performed for age distribution; odds ratio was performed to find the confounding factors.

Results

Embryonic and reproductive outcomes were comparable and not statistically significant in the study and control groups. Incidence of congenital anomalies was observed in singleton live births and twin live births in both the TESA-ICSI group and the EJS-ICSI group, but the difference was not statistically significant.

Conclusions

Our study revealed that congenital malformations in children born out of ICSI using testicular sperm and EJS were similar; no difference was observed in miscarriages between the testicular sperm-ICSI and EJS-ICSI group. Our data suggests that surgical sperm retrieval in couples with male factor infertility does not alter their reproductive outcome.

Study of differential proteomics in granulosa cells of premature ovarian insufficiency (POI) and the roles and mechanism of RAC1 in granulosa cells

In the present study, we focused on characterizing the proteome in granulosa cells in patients with biochemical premature ovarian insufficiency (bPOI) in order to identify differential proteins and investigate the fundamental mechanisms of POI. A total of 2688 proteins were identified based on the data-independent acquisition method, and 70 differentially expressed proteins were significant. Bioinformatic analyses, including gene expression pattern analysis, gene ontology enrichment analysis, Kyoto Encyclopedia of Genes and Genomes pathway analysis, and Search Tool for the Retrieval of Interacting Genes/Proteins analysis, revealed discrete modules and the underlying molecular mechanisms in bPOI. Importantly, we observed that Ras-related C3 botulinum toxin substrate 1 (RAC1) was downregulated in the granulosa cells of bPOI. Low expression of RAC1 may affect the development process of POI by affecting the proliferation, apoptosis, and hormone synthesis of granulosa cells. Downregulation of RAC1 expression in the KGN and COV434 cells inhibited cell proliferation, blocked cells in the G1/G0 phase, and promoted apoptosis. Western blot results showed that β-catenin and cyclin D1 in the KGN and COV434 cells transfected with RAC1-siRNA were downregulated, while P21 and Bax were upregulated. Knocking down RAC1 in the KGN cells or adding the RAC1 enzyme inhibitor to the human luteinized granulosa cells (hLGC) inhibited the synthesis of E₂, and the expression of aromatase and follicle-stimulating hormone receptor (FSHR) was reduced.

Aging endometrium in young women: molecular classification of endometrial aging-based markers in women younger than 35 years with recurrent implantation failure

BACKGROUND

To explore the differences between a population with premature endometrial aging and a population with normal endometrial status in young women with recurrent implantation failure (< 35 years).

METHODS

Systematic analysis of the endometrium transcriptome of 274 RIF women. The NMF algorithm was used for classification based on endometrial-specific aging markers in CellAge, and the endometrial receptivity, gene expression patterns, and clinical data were compared between the classifications.

RESULTS

Two hundred forty-five young RIF women could be divided into two clusters, in which the aging gene expression pattern of cluster 2 was closer to the reference cluster. Cluster 1 was characterized by high immune activity, while cluster 2 was characterized by high metabolic activity. Combined with clinical data, cluster 2 was worse than cluster 1 in window of implantation deviation rate and endometrial receptivity.

CONCLUSION

Premature aging of the endometrium exists in young women with RIF, and premature aging of the endometrium was associated with poor reproductive outcomes.

Micronucleus formation during early cleavage division is a potential hallmark of preimplantation embryonic loss in cattle

In assisted reproductive technology (ART)-derived embryos of non-rodent mammals, including humans and cattle, chromosome segregation errors are highly likely to occur during early cleavage division, resulting in aneuploidy, including mosaicism. However, the relationship between chromosomal segregation errors during early cleavage and subsequent embryonic development has not been detailed in these mammals. In the present study, we developed non-invasive live-cell imaging of chromosome segregation dynamics using a histone H2B-mCherry mRNA probe in bovine preimplantation embryos. Chromosome segregation errors in early cleavage affected blastocyst formation. Especially, embryos that underwent abnormal chromosome segregation (ACS) with multiple or large micronucleus formation rarely developed into blastocysts. Embryos with the severe ACS had prolonged cell cycle duration. After transfer of blastocysts with live-cell imaging of chromosome segregation to ten cows, six became pregnant and four of them gave full-term offspring. Interestingly, two of them were derived from blastocysts with ACS. Hence, chromosomal segregation errors with micronucleus formation during early cleavage can be a fatal hallmark of preimplantation embryogenesis in cattle. This technique has shown potential for understanding the relationship between chromosome segregation error and subsequent embryo development, and for selecting viable ART-derived embryos for medical and livestock production.

Out-of-pocket payment and patients' treatment choice for assisted reproductive technology by household income: a conjoint analysis using an online social research panel in Japan

BACKGROUND

Economic disparities affect access to assisted reproductive technology (ART) treatment in many countries. At the time of this survey, Japan provided partial reimbursement for ART treatment only for those in low- or middle-income classes due to limited governmental budgets. However, the optimal level of financial support by income class remains unclear.

METHODS

We conducted a conjoint analysis of ART in Japan in January 2020. We recruited 824 women with fertility problems aged 25 to 44 years via an online social research panel. They completed a questionnaire of 16 hypothetical scenarios measuring six relevant ART attributes (i.e., out-of-pocket payment, pregnancy rate, risk of adverse effects, number of visits to outpatient clinics, consultation hours and kindness of staff) and their relations to treatment choice.

RESULTS

Mixed-effect logistic regression models showed that all six attributes significantly influenced treatment preferences, with participants valuing out-of-pocket payment the most, followed by pregnancy rates and kindness of staff. Significant interactions occurred between high household income (≥ 8 million JPY) and high out-of-pocket payment (≥ 500,000 JPY). However, the average marginal probability of the highest-income patients (i.e., ≥ 10 million JPY, ineligible for the subsidy) receiving ART treatment at the average cost of 400,000 JPY was 47%, compared to 56 - 61% of other income participants, who opted to receive ART at an average cost of 100,000 JPY after a 300,000 JPY subsidy.

CONCLUSION

Our results suggest that out-of-pocket payment is the primary determinant in patients' decision to opt for ART treatment. High-income patients were more likely to choose treatment, even at a high cost, but their income-based ineligibility for government financial support might discourage some from receiving treatment.

Emergency department utilization for ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a rare, but serious, risk of assisted reproductive technologies. In severe cases, patients may present to the emergency department (ED) for assessment, treatment of related complications, and even in-patient admission. Significant effort has been made to reduce the incidence and complications of OHSS; however, it is unknown if these strategies have decreased patient presentation for treatment in the ED.

PURPOSE

To assess ED utilization for OHSS over time and to examine admission rates, patient demographics, and charges.

METHODS

Retrospective longitudinal study utilizing data from the Nationwide Emergency Department Sample Database and the National ART Surveillance System. All ED visits between 2006 and 2016 with an ICD-9 or -10 diagnosis of OHSS were included. Demographics including age, geographic location, and income quartile and alternative diagnoses, admission rates, overall charges, and number of stimulation cycles annually were assessed.

RESULTS

The number of ovarian stimulation cycles steadily increased from 2006 (n = 110,183) to 2016 (n = 157,721), while the number of OHSS-related ED visits remained relatively stable (APC 2.08, p = 0.14). Admission rates for OHSS decreased from 52.7% in 2006 to 33.1% in 2016 (APC -4.43%, p < 0.01). The average charge for OHSS-related ED visits almost doubled from 2006 to 2016 (APC 8.53, p < 0.01) and was significantly higher than charges for non-OHSS-related visits for age-matched controls (p < 0.01).

CONCLUSION

Despite an increase in total stimulation cycles, there was no significant change in the estimated number of patients presenting to the ED; however, admission rates significantly declined. These observations suggest a possible shift in the severity and/or management of OHSS during the study period.

Impact of in vitro fertilization state mandates for third party insurance coverage in the United States: a review and critical assessment

The American Society for Reproductive Medicine estimates that fewer than a quarter of infertile couples have sufficient access to infertility care. Insurers in the United States (US) have long considered infertility to be a socially constructed condition, and thus in-vitro fertilization (IVF) an elective intervention. As a result, IVF is cost prohibitive for many patients in the US. State infertility insurance mandates are a crucial mechanism for expanding access to fertility care in the US in the absence of federal legislation. The first state insurance mandate for third party coverage of infertility services was passed by West Virginia in 1977, and Maryland passed the country's first IVF mandate in 1985. To date, twenty states have passed legislation requiring insurers to cover or offer coverage for the diagnosis and treatment of infertility. Ten states currently have "comprehensive" IVF mandates, meaning they require third party coverage for IVF with minimal restrictions to patient eligibility, exemptions, and lifetime limits. Several studies analyzing the impact of infertility and IVF mandates have been published in the past 20 years. In this review, we characterize and contextualize the existing evidence of the impact of state insurance mandates on access to infertility treatment, IVF practice patterns, and reproductive outcomes. Furthermore, we summarize the arguments in favor of insurance coverage for infertility care and assess the limitations of state insurance mandates as a strategy for increasing access to infertility treatment. State mandates play a key role in the promotion of evidence-based practices and represent an essential and impactful strategy for the advancement of gender equality and reproductive rights.

Conception by fertility treatment and cardiometabolic risk in middle childhood

OBJECTIVE

To evaluate whether children conceived using assisted reproductive technology (ART) or ovulation induction (OI) have greater cardiometabolic risk than children conceived without treatment.

DESIGN

Clinical assessments in 2018-2019 in the Upstate KIDS cohort.

SETTING

Clinical sites in New York.

PATIENT(S)

Three hundred thirty-three singletons and 226 twins from 448 families.

INTERVENTION(S)

Mothers reported their use of fertility treatment and its specific type at baseline and approximately 4 months after delivery. High validity of the self-reported use of ART was previously confirmed. The children were followed up from infancy through 8-10 years of age. A subgroup was invited to participate in clinic visits.

MAIN OUTCOME MEASURE(S)

The measurements of blood pressure (BP), arterial stiffness using pulse wave velocity, anthropometric measures, and body fat using bioelectrical impedance analysis were performed (n = 559). The levels of plasma lipids, C-reactive protein, and hemoglobin A1c were measured using blood samples obtained from 263 children.

RESULT(S)

The average age of the children was 9.4 years at the time of the clinic visits Approximately 39% were conceived using fertility treatment (18% using ART and 21% using OI). Singletons conceived using fertility treatment (any type or using ART or OI specifically) did not statistically differ in systolic or diastolic BP, heart rate, or pulse wave velocity. Singletons conceived using OI were smaller than singletons conceived without treatment, but the average body mass index of the latter was higher (z-score: 0.41 [SD, 1.24]) than the national norms. Twins conceived using either treatment had lower BP than twins conceived without treatment. However, twins conceived using OI had significantly higher arterial stiffness (0.59; 95% CI, 0.03-1.15 m/s), which was attenuated after accounting for maternal BP (0.29; 95% CI, -0.03 to 0.46 m/s). Twins did not significantly differ in size or fat measures across the groups. The mode of conception was not associated with the levels of lipids, C-reactive protein, or glycosylated hemoglobin.

CONCLUSION(S)

Clinical measures at the age of 9 years did not indicate greater cardiometabolic risk in children conceived using ART or OI compared with that in children conceived without treatment.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov #NCT03106493.

Assisted reproductive technologies in Latin America: the Latin American Registry, 2019

RESEARCH QUESTION

What was the utilization, effectiveness and safety of assisted reproductive technology (ART) in Latin America during 2019?

DESIGN

This was a retrospective collection of multinational data on ART performed at 196 institutions from 15 countries.

RESULTS

A total of 106,918 initiated cycles, 18,133 deliveries and 21,096 births were reported. ART utilization was 24-558 cycles per million inhabitants. Women aged ≥40 years represented 32.9% of fresh IVF and intracytoplasmic sperm injection (ICSI) cycles. After removing freeze-all cycles, the delivery rate per oocyte retrieval was 17.3% for ICSI and 19.5% for IVF. Overall, single-embryo transfer (SET) represented 36.2% of fresh transfers, with a 19.5% delivery rate per transfer, increasing to 30.7% for elective SET and 32.7% for blastocyst elective SET (eSET). The delivery rate for double-embryo transfers (DET) was 27.8%, increasing to 37.1% after elective DET. This 6.4% increment in deliveries between eSET and elective DET resulted in a 12-fold increase in twin births. Furthermore, overall perinatal mortality was more than two-fold higher for twin compared with singleton deliveries. The delivery rate for frozen-thawed SET reached 28.1%, most being blastocyst transfers. Of all births, 72.3% were singletons, 26.4% twins and 1.3% triplets and higher multiples. Preterm deliveries reached 14.3% for singletons and 58.1% for twins. Perinatal mortality was 7.4‰ in singletons, 17.2‰ for twins and 62.9‰ for triplets or higher.

CONCLUSIONS

The number of initiated cycles has slowly increased in countries with laws or regulations facilitating access. FET cycles predominate and blastocyst SET are also increasing. The data show that, especially in young women and oocyte recipients, when there is more than one blastocyst for transfer, eSET should be the rule.

Fertility preservation practices for female oncofertility differ significantly across the USA: results of a survey of SREI members

PURPOSE

The field of oncofertility has maintained an important focus on improving access, yet standardized practices are lacking. To assess how female cancer patients are provided oncofertility care, we sought to determine provider-level differences and whether there are physician or practice characteristics that predict these variations.

METHODS

A cross-sectional survey was sent to SREI members. The survey included fifteen questions about physician practice characteristics and oncofertility cryopreservation protocols. Topics included ovarian stimulation protocols, fertilization techniques, stage of embryo cryopreservation, routine use of pre-implantation genetic testing for aneuploidy (PGT-A), and ovarian tissue cryopreservation (OTC). Statistical analyses assessed whether practice setting, geographic region, time in practice, and mandatory state insurance coverage had effects on cryopreservation protocols.

RESULTS

A total of 141 (17%) from diverse REI practice backgrounds completed the survey. The median number of new female oncofertility consults per year was 30 (range 1 to 300). Providers in academic settings treated more patients (median 40 vs. 15, p < 0.001). Providers in academic settings more often use gonadotropin-releasing hormone agonists (85% vs. 52%, p < 0.001) and perform OTC (41% vs. 4%, p < 0.001). Providers in academic practices were less likely to perform intracytoplasmic sperm injection in every cycle (37% vs. 55%, p = 0.032) and less likely to usually advise PGT-A (21% vs. 36%, p = 0.001). Mandated state insurance coverage had no effect on oncofertility practices.

CONCLUSION

Oncofertility practices vary among providers. Factors such as practice setting and region may affect the services provided. We do not yet know the best practices in oncofertility patients, and future research is needed.

The fatty acid composition in follicles is related to the developmental potential of oocytes up to the blastocyst stage: a single-centre cohort study

BACKGROUND

Advanced maternal age and obesity are associated with impaired female fertility. Moreover, fatty acids (FA) in follicular fluid (FF) play important roles in oocyte maturation and embryo development. However, the effects of body mass index (BMI), age, and FF FA composition on embryo development between days 3 and 5 and blastocyst stage on day 5 are still unclear.

METHODS

This study included 138 patients undergoing assisted reproductive technology (ART), which were divided into three BMI groups (18.5-24.9 kg/m² vs. 25.0-29.9 kg/m² vs. ≥ 30.0 kg/m²) and three age-related groups (20-30 years vs. 31-34 years vs. ≥ 35 years) which were compared for ART outcomes. Further, observations were divided into quartiles based on either of three parameters related to embryo outcome, i.e. (i) embryos developing between days 3 and 5 (ED3-5) and (ii) expanded blastocysts on day 5 (EB5), both expressed proportionally to the number of oocytes with two pronuclei (2PN), as well as (iii) the embryo utilization rate (EUR). Proportions of FF FA were then compared between Q1 and Q4, representing the quartile with the worst vs. the best embryo outcome, respectively. Finally, regression models were created to assess the relationships between BMI, age, FF total FA (TFA) concentration, relative proportions of specific FA and embryo outcome.

RESULTS

Patients of Q1 had higher proportions of FF C20:5n-3, C22:6n-3 and total n-3 PUFA than Q4 patients. Furthermore, Q4 patients tended to be younger than Q1 patients. Within the whole cohort, the proportion of C20:5n-3 negatively correlated with ED3-5/2PN and EUR, while EB5/2PN tended to be negatively correlated with age. Regression models within the overweight and obese group confirmed the negative relation between C20:5n-3 and ED3-5/2PN, but also indicated additional associations: C18:1n-9 and C20:4n-6 were positively associated with ED3-5/2PN and EUR, respectively while the proportion of C18:0 was negatively associated with EUR.

CONCLUSION

The proportions of n-3 PUFA, particularly C20:5n-3 and C22:6n-3 were reduced in the patients' quartile with the best embryo outcome. This group of patients was also younger. However, the embryo quality parameters of overweight/obese patients were not associated with age but were positively associated with FF C18:1n-9 and negatively with the proportions of C18:0 or C20:5n-3.

TRIAL REGISTRATION

This study' registration number was B670201627735.

Strategy for embryo transfer to improve pregnancy outcomes in advanced maternal age

The purpose of this retrospective study was to optimize the transplantation strategy for women of advanced maternal age to achieve live births within the shortest time. Data were collected from patients older than 40 years who underwent assisted reproductive therapy at our centre from 1 January 2009 to 31 December 2019. In total, 1023 cases of fresh cleavage embryo transfer (CET) cycles, 280 cases of frozen-thawed blastocyst transfer (FBT) cycles, and 26 cases of frozen-thawed CET (FCET) cycles were included. The main outcome was the live birth rate (LBR). The secondary outcomes were the clinical pregnancy rate (CPR) and neonatal outcomes. Multivariable logistic regression was performed to adjust for confounding factors. The blastocyst formation rate of patients older than 40 years was 23.5%, the freezing cycle rate was 19.8%, and the fresh-embryo transfer rate was 83.0%. The implantation rate, CPR, and LBR were significantly different among the CET, FCET, and FBT groups. There were no significant differences in multiple pregnancies and abortion rates among the groups, and neonatal outcomes were similar. Multivariate logistic regression analysis showed that, compared with the CET group, LBR did not increase in the FCET group, whereas LBR increased in the FBT group. For patients older than 40 years when having approximately eight embryos after fertilization, blastocyst transfer can be considered after fully discussing the advantages and disadvantages of blastocyst culture. Alternatively, CET can be performed first, followed by FBT if the cleavage embryo transfer is unsuccessful.

Impact of satellite clinics on geographic access to assisted reproductive technology services in the United States

Background

Many assisted reproductive technology (ART) centers utilize satellite clinics to expand reach and access to clinical services, but their contribution to lowering geographic barriers in access to care has not been examined. This study’s purpose is to determine the extent to which satellite clinics impact geographic access to ART and estimate the percentage of reproductive-age women who have geographic access to ART services.

Methods

A systematic web-search collected the locations of all main and satellite ART clinics in the United States (US). Driving times were calculated between satellite clinics and main clinics. The percentage of women with geographic access to care was characterized by clinic type using US Census Core Based Statistical Areas (CBSAs). Logistic regression was used to statistically model the presence of main and satellite clinics as a function of CBSA median income and female reproductive-age population.

Results

Four hundred sixty-nine main clinics with embryology labs and 583 satellite clinics were found in the US. Practices with satellite clinics tend to perform more ART cycles. Satellite clinics are located on average 66 minutes from their practice’s main clinic and 31 minutes from any main clinic. 22% of satellite clinics were in CBSAs without a main clinic. 46 M (72%) US reproductive-age women live in a CBSA with a main clinic, 5.1 M (8%) women live in a CBSA without a main clinic but at least one satellite clinic, and 13 M (20%) women live in an area with no ART clinic of either type. Female reproductive-age population was found to be a more important predictor of clinic presence than median income.

Conclusions

The majority of satellite clinics in the US are positioned in relative proximity to a main clinic. 85% of satellite clinics are located closer to the main clinic of other practices than to their own main clinic. Less than a quarter of ART satellite clinics expand geographic access to ART services by being located in areas without a main clinic, and the vast majority of practices with satellite clinics position their satellite clinics close to another practice’s main clinic.

Trial registration

Not applicable.

The newly non-uniform endometrial echogenicity on transvaginal ultrasound do not impact in vitro fertilization and embryo transfer success: A retrospective cohort study

OBJECTIVE

To evaluate the effect of newly non-uniform endometrial echogenicity diagnosed by transvaginal ultrasound on the outcome of pregnancy in vitro fertilization-embryo transfer (IVF-ET) during controlled ovarian hyperstimulation (COH) by retrospective cohort analysis.

METHODS

A retrospective cohort study of a total of 604 patients with newly non-uniform endometrial echogenicity from January 2013 to June 2017, each woman was matched with three control subjects of similar age (±1 year), type of infertility (primary or secondary), the protocol used for COH, and the number of ET cycles in our unit. The patients in the study group and control group were matched according to the strict 1:3 matching principle. Baseline characteristics and pregnancy outcomes were compared.

RESULTS

There were no statistically significant difference in baseline characteristics, live birth rate, biochemical pregnancy rate, clinical pregnancy rate, clinical pregnancy miscarriage rate and ectopic pregnancy rate between the two groups. But there were significant statistical differences in past history of uterine cavity surgery between the two groups (35.26% VS 21.19%), especially in history of endometrial polyp surgery (94.84% VS 90.10%).

CONCLUSIONS

Our results demonstrate the newly diagnosed non-uniform endometrial echogenicity during controlled ovarian hyperstimulation does not affect the pregnancy outcome of in vitro fertilization-embryo transfer, and fresh embryo transfer can be continued.

Diamour®, a newly vitrification device for human blastocysts, provides the same efficient perinatal outcomes as the commonly used Cryotop®

OBJECTIVE

The purpose of this study was to investigate the effectiveness of Diamour®, a newly developed vitrification device, for the ultra-rapid frozen storage of human blastocysts.

MATERIALS AND METHODS

Surplus blastocysts obtained using assisted reproductive technology at our clinic during a 2-year period (2018-2019) were assigned for vitrification with the Diamour® device in 2019 or a comparator device in 2018. We retrospectively compared outcomes (clinical pregnancy rate, abortion rate, live birth rate, and perinatal outcomes) between the two vitrification devices.

RESULTS

We obtained 228 blastocysts from 178 patients, and 118 blastocysts were cryopreserved using the Diamour® vitrification device and the other 110 were cryopreserved using a Cryotop®, the comparator device. We found no significant difference between the Diamour®-vitrified and comparator-vitrified blastocysts in clinical pregnancy rate (32.2% vs. 30.9%; p = 0.83), abortion rate (17.0% vs. 9.1%; p = 0.08), and live birth rate (25.4% vs. 26.4%; p = 0.87). The Diamour®-vitrified blastocysts yielded 30 live births, and the comparator-vitrified blastocysts 29. The two devices yielded no significant difference in birth weight (Diamour®: 3049 ± 337 g, comparator: 3008 ± 340 g; p = 0.65) and congenital abnormalities, with just 1 case (cleft lip) noted with Diamour® vitrification (p = 0.33). The devices also showed no significant differences in the incidence of gestational diabetes mellitus, hypertensive disorders of pregnancy, placenta previa, preterm birth, macrosomia, low birth weight, and delivery method.

CONCLUSION

The Diamour® device achieves outcomes similar to those of the currently widely used Cryotop® device for clinical pregnancy with frozen-thawed human blastocysts.

Patient and clinician experiences with cross-border reproductive care: A systematic review

OBJECTIVES

This review analyzes the experiences of patients and clinicians with regards to international cross-border reproductive care (CBRC) for the purpose of conception.

METHODS

Electronic databases PubMed, Embase, Web of Science, and Scopus were searched using 'medical tourism' AND 'assisted reproductive technology' from 1978 to 2020.

RESULTS

Predominant patient motivators for CBRC were cost and legality of assisted reproduction technology (ART) in one's home country, followed by cultural factors like shared language, religion, and cultural familiarity. Clinicians suggested global laws for CBRC would reduce the potential for exploitation of vulnerable populations but believed the enactment of international regulations unlikely and, even if enacted, difficult to enforce.

CONCLUSIONS

While patient and clinician experiences with CBRC varied, patients frequently cited financial and legal reasons for pursuing CBRC, while many providers had concern for the patient's safety.

CLINICAL PRACTICE IMPLICATIONS

This review recommends clinicians involved in family planning counsel patients seeking treatment abroad by: (i) informing patients of the risks and benefits of treatment abroad, (ii) establishing guidelines and standards for clinicians on resuming patient care post-CBRC, and (iii) creating a directory of reputable CBRC clinicians and experts.

Analysis of the risk of complications during pregnancy in pregnant women with assisted reproductive technology: a retrospective study using registry linkage from 2013 to 2018 in Shanghai, China

Background

To evaluate the differences in pregnancy outcomes between assisted reproductive technology (ART) patients and natural pregnant women in Shanghai, China in the past 6 years objectively. And to assess the feasibility of the research method of registry-database linkage in mainland China.

Methods

This retrospective study was conducted using registry-database linkage. A total of 8102 pregnancies with ART and 8096 parturients with spontaneous conception (SC) from 10 reproductive centers and 111 hospitals composed our retrospective study. The primary outcomes were the rates of obstetric complications (pregnancy-induced hypertention [PIH], gestational diabetes mellitus [GDM], placenta previa, mode of delivery, preterm birth [PTB], low birth weight [LBW], and macrosomia). The prenatal outcomes were compared between ART and SC parturients, frozen-thawed embryo transfer (FET) and fresh embryo transfer, and in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). We calculated odds ratios (ORs) and 95% confidence intervals (CIs).

Results

The final matching rate of the target population was 92% by using registry linkage. ART resulted in a higher rate of multiple birth, PTB, LBW, cesarean section, placenta previa and GDM compared with SC in the singleton cohort. In ART patients, pregnant women with FET had a significantly higher risk of PIH than those with fresh embryo transfer (14.1% Vs 9.3%, AOR1.528, 95% CI 1.303–1.793), but there was no difference between IVF and ICSI. FET is also related to the severity of PIH.

Conclusions

ART increased the rate of complications during pregnancy, the risk and severity of PIH in patients with FET was higher than that in patients with fresh embryo transfer. The registry-database linkage study is an objective and feasible research method in mainland China.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04846-1.

Dose-response association between maternal pre-pregnancy bodyweight and gestational diabetes mellitus following ART treatment: a population-based cohort study

BACKGROUND

The impact of maternal pre-pregnancy bodyweight on gestational diabetes mellitus (GDM) following assisted reproductive technology (ART) treatment has been insufficiently investigated. The aim of this study was to investigate the association between maternal pre-pregnancy bodyweight and GDM following ART.

METHODS

From January 2014 to March 2019, this population-based retrospective cohort study included pregnancies achieved by ART treatment in a pregnancy registration database in China. Multivariate regression analysis and restricted cubic splines were used to explore the association between bodyweight and GDM.

RESULTS

A total of 6,598 pregnancies were included. The incidence of GDM was 26.0% (1715/6598). A total of 868 (13.2%) pregnant women were underweight, 665 (10.8%) were overweight, and 145 (2.20%) were obesity. We found a linear dose-response relation between maternal body mass index and GDM by restricted cubic splines, where one unit body mass index increase was associated with the 15% elevated risk of GDM (adjusted odds ratio [OR] 1.15, 95% CI 1.08-1.22). Compared to the normal weight group, maternal underweight was associated with lower risk of GDM (adjusted OR 0.68, 95% CI 0.57-0.82), while increased risk was found for overweight (adjusted OR 1.54 95% CI 1.29-1.84) and obesity (adjusted OR 1.74, 95% CI 1.23-2.47).

CONCLUSIONS

Our study found a linear dose-effect relationship between pre-pregnancy bodyweight and GDM following ART treatment. The findings in this study support the clinical recommendation of advising women with overweight or obesity to lose weight prior to ART treatment.

Severe maternal morbidity and maternal mortality associated with assisted reproductive technology

OBJECTIVE

To assess the association between use of assisted reproductive technologies (ART) and severe maternal morbidity and maternal mortality (SMM).

METHODS

We carried out a cohort study that included all hospital deliveries at ≥20 weeks gestation in Canada (excluding Québec) between April 2009 and March 2018. Outcomes of interest included composite SMM and SMM types (e.g., severe preeclampsia, HELLP syndrome, and eclampsia; severe hemorrhage; acute renal failure). Multivariable regression was used to estimate crude and adjusted rate ratios (RR and aRR) and 95% confidence intervals (CI).

RESULTS

The study included 2 535 056 women, of whom 72 023 (2.8%) delivered following the use of ART. The composite SMM rate for women who used ART was 34.7 per 1000 deliveries (95% CI 33.0-36.0) versus 11.5 per 1000 deliveries (95% CI 11.4-11.6) for women who did not use ART (RR 3.01; 95% CI 2.89-3.14). ART use was associated with SMM types such as severe preeclampsia, HELLP syndrome, and eclampsia (RR 3.50; 95% CI 3.27-3.73), severe hemorrhage (RR 3.58, 95% CI 3.27-3.92), and acute renal failure (RR 6.79; 95% CI 5.78-7.98). Associations between ART and composite SMM were attenuated but remained elevated after adjusting for maternal characteristics (aRR 2.34; 95% CI 2.24-2.45). Women who used ART and had a multi-fetal pregnancy had a 4.7 times higher rate of composite SMM compared with women who did not use ART and delivered singletons.

CONCLUSION

Women who deliver following the use of ART have increased risks of SMM and require counselling that includes mention of the lower risks of SMM associated with ART-conceived singleton pregnancy.

Preconception period in women and men undergoing Assisted Reproduction: A gender approach for reproductive health

OBJECTIVE

To evaluate lifestyle and risk factors playing a role in increasing the burden of cardiovascular diseases and to increase attention of clinicians who should envision a broader preconception approach in ART, not only in women but also in men.

STUDY DESIGN

In this cross-sectional study we investigated 90 Caucasian couples, referred to the Internal Medicine Clinic at the Assisted Reproductive Technology Centre, in order to better define in preconceptional period their cardiovascular risk profile, based on metabolic parameters and lifestyle behaviours.

RESULTS

We observed two-fold increase of overweight in men in comparison to women (p = 0.006). Values of waist ≥ 94 cm in men and ≥ 80 cm in women were present in 53.3% of men and 32.2% of women (p = 0.007). Similarly, values of WHR according to gender cut-off, were present in 64.4% of men and in 32.2% of women (p < 0.0001). In men we observed a significantly higher prevalence of hypertension (p = 0.02), significantly lower HDL-c (p = 0.001) and higher levels of total cholesterol (p = 0.01), LDL-c and triglycerides (p = 0.001). Sedentary behaviour was observed in about 60% of both genders. Alcohol consumption was reported by 42.2% of men and 26.7% of women (p = 0.04) and smokers were more prevalent among women (26.7%) than men (24.4%). We observed a lower adherence to Mediterranean Diet related to consumption of red meat and meat products (p = 0.02), as well as of legumes consumption (p = 0.01) in men, whereas sweet/pastries (p = 0.05) and fruits (p = 0.06) in women. Men and women with normal BMI, waist and WHR, showed a higher Mediterranean diet adherence in comparison to overweight/obese study population(p < 0.001). Finally, higher education level predicted the higher Mediterranean diet adherence in both gender (p = 0.01 for men, p = 0.03 for women).

CONCLUSIONS

This study paid attention on preconceptional health in couples planning ART. Women have a greater biological role in childbearing, whereas the role of men is underestimated. The need to conceive through ART offers a window of opportunity not only to evaluate cardiovascular profile and lifestyle factors in couples prior to conception, but also to manage comorbidities and promote health behaviours in order to improve fertility and health outcomes in both women and men at short and long-term.

Analysis of IVF/ICSI outcomes in infertile women with early-stage endometrial cancer and atypical endometrial hyperplasia after conservative treatment

PURPOSE

To investigate the in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes and identify factors that might affect live births in patients with early-stage endometrial cancer (EEC) and atypical endometrial hyperplasia (AEH).

METHODS

This retrospective study was performed in a tertiary hospital. Patients (n = 123) with EEC or AEH, who underwent IVF/ICSI treatment between January 2010 and December 2019, were divided into a live birth group and a non-live birth group. Clinical characteristics and IVF/ICSI outcomes were assessed.

RESULTS

A total of 123 patients (28 with EEC and 95 with AEH) underwent 215 ovarian stimulation cycles, resulting in 121 fresh embryo transfer (ET) and 108 frozen-thawed ET. Among 229 ET cycles, 91 (23.7%) of 384 embryos were implanted and 86 pregnancies were achieved, including five ectopic pregnancies (5.8%), 28 miscarriages (32.6%), and 53 live births (61.6%). The clinical pregnancy and live birth rates in each ET cycle were 37.6% and 23.1%, respectively. Fifty-one patients gave birth to 57 live neonates, and the cumulative live birth rate was 41.46%. Multiple logistic regression analysis showed that maternal age, histological type, thin endometrium, and time after complete remission (CR) to IVF cycle started were significantly associated with live births.

CONCLUSIONS

The live birth rate after IVF/ICSI is promising in infertile patients with EEC and AEH. A shorter interval between CR and IVF/ICSI treatment might be a positive factor, while age > 35 years, endometrial thickness < 8 mm on the day of ET, and degree of endometrial lesion progressing into carcinoma can negatively influence IVF/ICSI outcomes.

Down syndrome live births following assisted reproductive technology in Japan: a nationwide survey between 2007 and 2016

PURPOSE

The use of assisted reproductive technology (ART) and prenatal genetic testing have become more widespread in line with an increase in maternal age. However, the effect of the introduction of non-invasive prenatal testing (NIPT) in April 2013 on pregnancy outcomes in Japan, including the prevalence of Down syndrome live births following ART, has not been investigated. This study aimed to evaluate the trends in the prevalence of Down syndrome live births following ART in Japan.

METHODS

This population-based retrospective study used the Japanese nationwide ART registry. All clinical pregnancies resulting in live births, stillbirths, and termination of pregnancy (TOP) following ART from 2007 to 2016 were included. Pregnancy outcomes involving infants with Down syndrome were evaluated.

RESULTS

Among 351,808 pregnancies, the proportion of mothers with advanced age increased significantly from 2007 to 2016 (from 49.5 to 62.4% and 8.9 to 17.8% for mothers aged ≥ 35 and ≥ 40 years, respectively). The proportion of live births with Down syndrome was 77.3% in 2007, which remained consistent until 2012, but then decreased significantly to 45.1% after 2013 (P < 0.001). The prevalence of Down syndrome live births increased up to 2012 (19.5/10,000 live births), decreased significantly in 2013 (12.1/10,000 live births), and then remained almost stable (11.1-14.7/10,000 live births).

CONCLUSION

The introduction of NIPT balanced the prevalence of Down syndrome live births following ART with recent increasing maternal age in Japan.

The impact of biparental hepatitis B virus infection on pregnancy outcomes in patients undergoing assisted reproductive technology treatment: a systematic review and meta-analysis

PURPOSE

To evaluate the association between biparental hepatitis B virus (HBV) infection (hepatitis B surface antigen [HBsAg] seropositivity) and pregnancy outcomes in patients undergoing assisted reproductive technology (ART) treatment, including clinical pregnancy rate (CPR) and live birth rate (LBR).

METHODS

We searched various literature databases from the earliest date available until May 20, 2021, including PubMed, Embase, Medline, Web of Science, Scopus, CNKI, and Wangfang. Four patterns of biparental HBV infection for pregnancy outcomes following ART were synthesized separately by using random-effects model. We also performed subgroup analyses (matched or unmatched) and two forms of sensitivity analysis.

RESULTS

A total of 25 retrospective cohort studies, involving more than 19,269 couples, were included. Maternal and paternal HBV co-infection (crude relative risk [cRR]: 0.58, 95% confidence interval: 0.28-1.23), either maternal or paternal infection (cRR: 1.05, 0.88-1.24), maternal HBV infection alone (cRR: 0.96, 0.79-1.16), or paternal HBV infection alone (cRR: 1.02, 0.91-1.13) were not associated with significant reductions in CPR at per woman level. These patterns of infection were also not significantly associated with decreased LBR at per woman level. However, paternal HBV infection alone reduced CPR (adjusted odds ratio: 0.54, 0.33-0.86) and LBR (cRR: 0.52, 0.28-0.99) at per cycle level. Subgroup analyses and sensitivity analyses were mostly consistent with the primary results.

CONCLUSIONS

Paternal HBV infection alone probably decrease CPR after ART at per cycle level. However, maternal HBV infection was not associated with reductions in CPR and LBR in women undergoing ART at per woman level.

Exposure to air pollution is associated with congenital anomalies in the population born by in vitro fertilization

BACKGROUND

Congenital anomalies (CAs) are the leading causes for children's disabilities and mortalities worldwide. The associations between air pollution and CAs are not fully characterized in fetuses born by in vitro fertilization (IVF) who are at high risk of congenital anomalies.

METHODS

We conducted a cross-sectional study including 16,971 IVF cycles from three hospitals in Hebei Province, China, 2014-2019. Air quality data was obtained from 149 air monitoring stations. Individual average daily concentrations of PM_2.5, PM₁₀, NO₂, SO₂, CO, and O₃ were estimated by spatiotemporal kriging method. Exposure windows were divided into 5: preantral follicle period, antral follicle period, germinal period, embryonic period and early fetal period. Logistic generalized estimating equations were used to estimate the associations between air pollutants and overall or organ-system specific congenital anomalies. Negative control exposure method was used to detect and reduce bias of estimation.

RESULTS

We found increasing levels of PM_2.5 and PM₁₀ were associated with higher risk of overall congenital anomalies during early fetal period, equating gestation 10-12 weeks (OR: 1.05, 95% CI: 1.02-1.09, p = 0.013 for a 10 μg/m³ increase of PM_2.5; OR: 1.03, 95% CI: 1.01-1.06, p = 0.021 for a 10 μg/m³ increase of PM₁₀). Cleft lip and cleft palate were associated with PM₁₀ in germinal period and early fetal period. The CAs of eye, ear, face and neck were related to CO in preantral follicle stage. We did not find an association between chromosome abnormalities and air pollution exposure.

CONCLUSIONS

We concluded that ambient air pollution was a risk factor for congenital anomalies in the fetuses conceived through IVF, especially exposure in early fetal period.

Preliminary findings of age and male sexual characteristics andand potential effect to semen characteristics and cryopreservation of the critically endangered Bornean orangutan in Malaysia

Bornean orangutan is a critically endangered non-human primate; however, the threat of extinction is not merely from poaching and habitat loss. Orangutan survival is also threatened by the genetic loss and genetic bottleneck due to the low effective population, prompting the dire need for an immediate genetic preservation program through systematic biobanking and assisted reproductive technology (ART). This study aims to provide integral data to the semen characteristics, extension, and cryopreservation of the Bornean orangutan and the potential relationship to male traits. Five captive orangutans from Sepilok Orangutan Rehabilitation Centre (SORC) with a mean body weight of 52.81 ± 7.00 kg were used for this study. Semen collection was performed using electroejaculation (EE) under complete general anesthesia. Semen was subjected to macroscopic and microscopic evaluation while testicular measurement was obtained using digital calipers. The semen characteristics of the orangutans are volume (778 ± 250.21 µl), pH (7.80 ± 0.25), concentration (32.38 ± 17.40 × 10⁶ sperm/ml), total motility (61.00 ± 12.88%), adjusted motility index (48.76 ± 11.32%), live spermatozoa (77.75 ± 6.94%) and normal spermatozoa (11.48 ± 11.34%). Analysis of variance statistical analysis test was used to compare the significant difference between means, at (p < 0.05). Spermatozoa concentration was the only significant different parameter between individuals. Testes biometry parameters are statistically significant between the flanged and unflanged individuals. Live spermatozoa are different in adult and sub-adult individual while teratospermia was found to be consistently high in all individuals. Chilled and post-thaw quality after cryopreservation suggests promising survivability of spermatozoa. Semen collection with EE yields a consistent and acceptable quality of spermatozoa for cryopreservation, biobanking purposes, and potential application of ART.

Antiphospholipid antibodies in women with recurrent embryo implantation failure: A systematic review and meta-analysis

OBJECTIVE

Antiphospholipid antibodies (aPL) are related to poor pregnancy outcomes, but their effect on embryo implantation is unclear. We aimed to assess the prevalence of different aPL in women with recurrent implantation failure (RIF).

METHODS

We searched studies in PubMed (MEDLINE), Scopus and Cochrane Library. Quality of studies was scored by the Newcastle-Ottawa Scale and risk of bias assessment by items described in RevMan5 software. Statistical analyses were made using random-effects model and presented as pooled Odds Ratio (OR), 95% confidence interval (CI). Heterogeneity was assessed by I²% and D²%.

RESULTS

This systematic review and meta-analysis included 17 studies and showed a high degree of variability in aPL positivity in RIF. In the latter, the risk of bias assessment suggested unclear bias on study performance with a median sample size and interquartile range for RIF patients and fertile women of 96 (57-417) and 100 (60.5-202.5), respectively. Among the criteria aPL, IgG anticardiolipin autoantibodies (OR 5.02, 95% CI [1.95, 12.93]) were associated with RIF. Within the non-criteria aPL, anti-β2 glycoprotein I-IgA (OR 64.8, 95% CI [9.74, 431.0]), and antiphosphatidylglycerol-IgG and IgM (OR 10.74, 95% CI [5.25, 22.0]; OR 4.26, 95% CI [1.76,10.31]; respectively) were associated with RIF, too.

CONCLUSIONS

Anticardiolipin-IgG is a prevalent autoantibody in women with RIF. Three other non-criteria aPL, aβ2GP I-IgA, aPG-IgG and aPG-IgM also present a positive rate in RIF. Overall, these results advise about testing them as indicators of RIF risk in women seeking IVF treatment.

Mitochondrial supplementation of Sus scrofa metaphase II oocytes alters DNA methylation and gene expression profiles of blastocysts

Background

Mitochondrial DNA (mtDNA) copy number in oocytes correlates with oocyte quality and fertilisation outcome. The introduction of additional copies of mtDNA through mitochondrial supplementation of mtDNA-deficient Sus scrofa oocytes resulted in: (1) improved rates of fertilisation; (2) increased mtDNA copy number in the 2-cell stage embryo; and (3) improved development of the embryo to the blastocyst stage. Furthermore, a subset of genes showed changes in gene expression. However, it is still unknown if mitochondrial supplementation alters global and local DNA methylation patterns during early development.

Results

We generated a series of embryos in a model animal, Sus scrofa, by intracytoplasmic sperm injection (ICSI) and mitochondrial supplementation in combination with ICSI (mICSI). The DNA methylation status of ICSI- and mICSI-derived blastocysts was analysed by whole genome bisulfite sequencing. At a global level, the additional copies of mtDNA did not affect nuclear DNA methylation profiles of blastocysts, though over 2000 local genomic regions exhibited differential levels of DNA methylation. In terms of the imprinted genes, DNA methylation patterns were conserved in putative imprint control regions; and the gene expression profile of these genes and genes involved in embryonic genome activation were not affected by mitochondrial supplementation. However, 52 genes showed significant differences in expression as demonstrated by RNAseq analysis. The affected gene networks involved haematological system development and function, tissue morphology and cell cycle. Furthermore, seven mtDNA-encoded t-RNAs were downregulated in mICSI-derived blastocysts suggesting that extra copies of mtDNA affected tRNA processing and/or turnover, hence protein synthesis in blastocysts. We also showed a potential association between differentially methylated regions and changes in expression for 55 genes due to mitochondrial supplementation.

Conclusions

The addition of just an extra ~ 800 copies of mtDNA into oocytes can have a significant impact on both gene expression and DNA methylation profiles in Sus scrofa blastocysts by altering the epigenetic programming established during oogenesis. Some of these changes may affect specific tissue-types later in life. Consequently, it is important to determine the longitudinal effect of these molecular changes on growth and development before considering human clinical practice.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13072-022-00442-x.