Impact of age, clinical conditions, and lifestyle on routine semen parameters and sperm kinematics

Age related semen parameters and ICSI pregnancy outcomes of 8046 men in Turkey over a 9-year period

The effect of paternal age on fertility remains unclear. This retrospective study aims to examine the impact of male age on semen parameters and the reproductive outcomes of men admitted to an infertility center over a 9-year period. A total of 8046 patients were included in the study. Men were divided into four age groups. The groups were evaluated for semen parameters and reproductive outcome. The 21-30 year group presented lower sperm concentrations in comparison to those aged 31-40 and 41-50, yet shared a similar concentration to those over 50 years of age. Moreover, grades A and B decreased significantly in men aged over 50 years. The highest progressive motility and normozoospermia were observed in the age group 31-40 years while men over 50 years of age had the highest rates of asthenozoospermia and oligoasthenozoospermia. Furthermore, live birth results were reported in 5583 of the patients who underwent intracytoplasmic sperm injection (ICSI) and were found highest between 31-40 years of age. To our knowledge, this is the largest study in Turkey focusing on male age-related semen parameters and ICSI pregnancy outcomes. The study demonstrates that age is a significant factor for semen quality and live birth.

Benchmarks defining high-quality sperm in the common marmoset (Callithrix jacchus)

BACKGROUND

Common marmosets (Callithrix jacchus) are increasingly recognized as valuable nonhuman primates (NHPs) for biomedical research due to their small size and short reproductive cycle and lifespan relative to other NHP species. Maximizing the utility of captive research marmosets, including genetically manipulated animals, will require the use of assisted reproductive techniques (ART) including manipulation, storage, and sharing of marmoset sperm. Here, we identify characteristics of high-quality semen samples and validate a simple method for selecting high-quality sperm.

METHODS

Computer-assisted sperm analysis (CASA) was used to evaluate sperm quality in semen samples collected from 44 marmosets and assessed the use of the swim-up method for the selection of high-quality sperm was also tested in half the samples as a potential means to optimize in vitro fertilization or intrauterine insemination.

RESULTS

For each reference parameter, samples at or below the 5th percentile were categorized as abnormal sperm, while those above the 5th percentile were considered to be normal. Among normal samples, those at or above the 50th percentile were categorized as high-quality. High-quality semen samples exhibited the following characteristics: semen volume ≥ 30 µL; sperm count ≥ 107/ejaculate; total motility ≥ 35%; and normal morphology ≥ 5%. Sperm isolated by swim-up exhibited superior sperm progressive motility (19.7% ± 4.5 vs. 5.6% ± 2.1; P = 0.01) and normal morphology (13.1 ± 1.59 vs. 7.65 ± 1.1; P < 0.001) compared with unselected sperm.

CONCLUSION

This study defines robust, statistically supported reference values for evaluating marmoset semen samples to assist with the identification of optimal sperm donors and the selection of high-quality sperm samples for assisted reproduction. Ultimately, these reference values combined with a validated selection method will contribute to consistent standards for the international sharing of genetically diverse and/or gene-edited marmoset sperm for research and reproduction.

Association between body mass index and semen quality: a systematic review and meta-analysis

The continuous decline of human semen quality during the past decades has drawn much concern globally. Previous studies have suggested a link between abnormal BMI and semen quality decline, but the results remain inconsistent. This systematic review and meta-analysis aimed to evaluate the association between body mass index (BMI) and semen quality. We searched PubMed, Embase, and Web of Science for eligible studies from inception to April 17, 2022. We considered men with BMI < 25.0 kg/m2 as the reference and calculated the pooled weighted mean difference of men with overweight (BMI 25.0-29.9 kg/m2), obesity (BMI ≥ 30.0 kg/m2), class I obesity (BMI 30.0-34.9 kg/m2), and class II/III obesity (BMI ≥ 35.0 kg/m2). A total of 5070 articles were identified, of which 50 studies were included (71,337 subjects). Compared with men with BMI < 25.0 kg/m2, men with obesity had an average reduction of 0.24 ml in semen volume, 19.56 × 106 in total sperm number, 2.21% in total motility, 5.95% in progressive motility, and 1.08% in normal forms, respectively, while men with overweight had an average reduction of 0.08 ml in semen volume and 2.91% in progressive motility, respectively. The reduction of semen quality was more pronounced among men with obesity than that among men with overweight. Moreover, significant reductions in semen quality were identified in men with different classes of obesity, which were more pronounced in men with class II/III obesity than that in men with class I obesity. Across men from the general population, infertile or subfertile men, and suspiciously subfertile men, we identified significant semen quality reductions in men with obesity/overweight. In conclusion, obesity and overweight were significantly associated with semen quality reductions, suggesting that maintaining normal weight may help prevent semen quality decline.

Impact of heat waves on semen quality: A retrospective study in Argentina between 2005 and 2023

Heat waves, defined as periods with daily temperatures surpassing the historical average for a specific region, have become more frequent worldwide in recent years. Previous studies have reported a negative association between temperature and semen quality, but the focus has mainly been on Asian and European populations. The study included 54,926 men (18-60 years) undergoing routine semen analysis between 2005 and 2023 at CEUSA-LAEH andrology unit, in Buenos Aires, Argentina. Hourly temperature readings were provided by the Servicio Meteorológico Nacional. R programming (R Studio v2022.07.2) was used to define heat waves, calculate key characteristics, visualize results, and perform statistical tests at the IBYME laboratory. During the period studied, a total of 124 days had heat waves (defined after at least 3 consecutive days with 32.3 °C and 22 °C). Men exposed to heat waves during spermatogenesis exhibited lower sperm number (concentration and count; P < 0.0001) and decreased normal morphology (percentage of normal sperm and normal motile count; P < 0.05) compared to those not exposed. These differences were most pronounced between semen samples from years with several heat waves (2013, 2023) and none (2005, 2007, 2016), displaying 4-5 times higher fold changes (P < 0.05). Further analysis employing multiple regression revealed a significantly negative association between semen quality and heat wave length, suggesting that a prolonged exposure may be more detrimental than an acute exposure. Subsequent analysis focusing on prolonged exposure (≥6-days heat wave) during spermatogenesis revealed a negative (P < 0.05) association between early exposure (spermatocytogenesis: 64-90 days prior semen collection) and semen quality. This study underscores the negative association between early exposure to heat waves during sperm development and semen quality, raising concerns about its possible association with the worldwide declining male fertility. A comprehensive collaborative approach is crucial, involving global governmental policies, sustainable practices, and coordinated efforts across scientific, healthcare, and policy domains.

Assessment of male creatinine levels and fecundity in couples planning pregnancy: a national cohort study in China

STUDY QUESTION

Is there an association between male creatinine levels and time to pregnancy (TTP) in couples planning pregnancy?

SUMMARY ANSWER

Low and high male creatinine concentrations were associated with reduced couple fecundity.

WHAT IS KNOWN ALREADY

Abundant evidence suggests male creatinine dysfunction is associated with infertility in males with kidney diseases. However, the association of preconception creatinine levels with reduced fecundity among general reproductive-aged couples lacks evidence from an in-depth population study.

STUDY DESIGN, SIZE, DURATION

Based on the population-based cohort study from the National Free Preconception Check-up Projects, 4 023 204 couples were recruited and met the inclusion criteria from 1 January 2015 to 31 December 2017. They were planning pregnancy and were followed up every 3 months until achieving pregnancy as detected by gynaecological ultrasonography or were followed up for 1 year for the analysis of TTP.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Cox regression models were used to estimate hazard ratios (HRs) and 95% CI for creatinine deciles. Restricted cubic spline regression was adopted for the dose-response relationship of creatinine with HRs. R statistical software was used for data analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

Of the included participants, 2 756 538 (68.52%) couples successfully conceived. The median male serum creatinine was 81.50 μmol/l. Compared with the reference group (78.00-81.49 μmol/l) including the median creatinine, fecundity in the first (≤64.89 μmol/l), second (64.90-69.99 μmol/l), third (70.00-73.99 μmol/l), and tenth (≥101.00 μmol/l) deciles decreased by 8%, 5%, 2%, and 1%, respectively (Decile 1 Adjusted HR 0.92, 95% CI 0.91-0.92; Decile 2 Adjusted HR 0.95, 95% CI 0.95-0.96; Decile 3 Adjusted HR 0.98, 95% CI 0.97-0.99; Decile 10 Adjusted HR 0.99, 95% CI 0.98-0.99). An inverse-U-shaped association was consistently presented among males such that non-inferiority for fecundity was shown when creatinine was in the 81.66-104.90 μmol/l range (P for non-linearity < 0.001). For males over 40 years old, the risk of fecundity impairment was more obvious and the recommended range of creatinine levels for TTP was reduced and more narrow, compared with that for younger males.

LIMITATIONS, REASONS FOR CAUTION

Not including the time couples spend preparing for pregnancy before enrolment would lead to an overestimation of fecundity; additionally some couples place pregnancy plans on hold due to special emergencies, which would not have been recognized. Due to the lack of information regarding semen quality, psychological factors, sexual intercourse frequencies, and hazardous environmental factors, we could not adjust for these factors. Some variates were self-reported and dichotomized, which were prone to bias. Direct variables reflecting muscle mass and impaired kidney function were lacking. Thus, extrapolation should be done with caution.

WIDER IMPLICATIONS OF THE FINDINGS

Male creatinine is associated with couples' fecundity and the relationship varied by age. This study provides a better understanding of the potential implications and significance of different creatinine levels and their association with the clinical significance regarding couples' fecundity.

STUDY FUNDING/COMPETING INTEREST(S)

This research has received funding from the National Natural Science Foundation of China (Grant No. 81872634), the Basic Research Funds of Central Public Welfare Research Institutes of China (Grant No. 2023GJZ03), the National Key Research and Development Program of China (Grant No. 2016YFC1000307), and the Project of National Research Institute for Family Planning (Grant No. 2018NRIFPJ03), People's Republic of China. The authors have no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

A novel homozygous mutation in the DNAAF3 gene leads to severe asthenozoospermia and teratospermia

Primary ciliary dyskinesia (PCD) is an autosomal recessive genetic disorder characterized by ultrastructural defects in the cilia or flagella of cells, causing respiratory abnormalities, sinusitis, visceral transposition, and male infertility. DNAAF3 plays an important role in the assembly and transportation of axonemal dynein complexes in cilia or flagella and has been shown to be associated with PCD. To date, only two cases of PCD with infertility associated with DNAAF3 mutations have been reported, and no mouse models for this gene have been successfully constructed. This study was conducted on an infertile Chinese male patient with a history of bronchitis. Examination of the patient's semen revealed severe asthenozoospermia and teratospermia. Whole exome sequencing revealed a new homozygous loss-of-function DNAAF3 mutation. CRISPR-Cas9 gene-editing technology was used to construct the same mutation in C57/B6 mice, revealing that homozygous C57/B6 mice were characterized by severe hydrocephalus and early death. The results of this study expand the mutation spectrum of DNAAF3 and confirm its correlation with PCD pathogenesis. This study provides new insights on the mechanisms underlying male infertility related to DNAAF3 mutation and PCD.

The effects of vitamin E supplementation on sperm parameters, chromatin integrity, and gene expression before and after freezing in aged mice

OBJECTIVE

Some age-related testicular changes, such as Sertoli cell vacuolization and blood-testis barrier breakdown, reduce total sperm production and male fertility. Therefore, this study investigated the effect of vitamin E on restoring testicular function in aged mice. Sperm cryo-resistance was also assessed.

METHODS

Twenty-eight 48-week-old male Naval Medical Research Institute mice were divided into four groups for a daily gavage of vitamin E: the control group received distilled water, while the three treatment groups were administered 100, 200, and 400 mg/kg, respectively, for 4 weeks. Subsequently, semen analyses, DNA fragmentation index (DFI), and protamine deficiency tests were conducted. Testicular histology, tissue antioxidant enzyme activity, and gene expression levels were also assessed.

RESULTS

The two higher dosages of vitamin E were associated with a higher sperm count, greater progressive motility, and improved sperm morphology (p<0.05). These benefits were also evident after sperm freezing (p<0.05). Although chromatin abnormalities increased following vitrification, the treatment groups showed better outcomes (p<0.05). The tubular diameter, epithelium height, and luminal diameters remained unchanged with age. The tissue antioxidant capacity was greater in the groups receiving the high doses of vitamin E. Additionally, significant increases in inhibitor of DNA binding protein-4 (Id4) and GDNF family receptor alpha-1 (Gfra1) expression were observed in the higher vitamin E dosage groups, and promyelocytic leukemia zinc finger protein (Plzf) expression was notably present in the 400 mg/kg treatment group compared to the control group (p<0.05).

CONCLUSION

Antioxidant supplementation might enhance reproductive outcomes in aging males. The observed effects included improved sperm cryo-resistance, which is advantageous for future applications such as sperm freezing or fertility preservation.

Effect of paternal age on clinical outcomes of in vitro fertilization-embryo transfer cycles

Purpose

This study aimed to investigate the impact of paternal age > 40 years on clinical pregnancy and perinatal outcomes among patients undergoing in vitro fertilization treatment.

Methods

We selected 75 male patients (aged > 40 years) based on predefined inclusion and exclusion criteria. Propensity score matching was performed in a 1:3 ratio, resulting in a control group (aged ≤ 40 years) of 225 individuals. Various statistical tests, including the Mann-Whitney U test, Chi-square test, Fisher's exact test, and binary logistic regression, were used to analyze the association between paternal age and clinical outcomes.

Results

We found no statistically significant differences in semen routine parameters, clinical pregnancy outcomes, and perinatal outcomes between paternal aged > 40 and ≤ 40 years. However, in the subgroup analysis, the live birth rate significantly decreased in those aged ≥ 45 compared to those aged 41-42 and 43-44 years (31.25% vs. 69.23% and 65%, respectively; all p < 0.05). Additionally, the clinical pregnancy rate was significantly lower among those aged ≥ 45 than among those aged 41-42 (43.75% vs. 74.36%; p=0.035).

Conclusion

Paternal age ≥ 45 years was associated with lower live birth and clinical pregnancy rates.

Elucidating the impact of Y chromosome microdeletions and altered gene expression on male fertility in assisted reproduction

BACKGROUND

Genetic abnormalities like Y chromosome microdeletions are implicated in male infertility. This study investigated the association of azoospermia factor (AZF) region microdeletions with unsuccessful assisted reproductive techniques (ART), including in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).

METHODS

This cross-sectional analysis study examined 80 Iranian oligospermic men (mean age 34 years) with prior failed ICSI and IVF cycles (IR.IAU.TNB.REC.1401.041). Semen analysis evaluated quantity/quality parameters based on World Health Organization guidelines. Participants were stratified by sperm DNA fragmentation (SDF) levels into: control (SDF < 15%, n = 20), mild elevation (15% ≤ SDF ≤ 30%, n = 60), and high (SDF > 30%, n = 20). Multiplex PCR mapped AZF microdeletions in the high SDF group. The AZF-associated genes were selected by RNA Seq analysis, and the candidate genes were checked for expression level by real-time PCR.

RESULTS

High SDF individuals exhibited poorer semen metrics, including 69% lower sperm concentration (P = 0.04) than those without SDF. Of this subset, 45% (9/20 men) harboured predominately AZF microdeletions. Men with AZF microdeletions showed higher SDF (32% vs 21%, P = 0.02) and altered AZF-associated genes expression. As USP9Y 3-fold, UTY 1.3-fold, and BPY2 1-fold revealed up-regulation, while IQCF1 8-fold, CDY 6.5-fold, DAZ 6-fold, and DDX3Y 1-fold underwent down-regulation. The PAWP gene was also down-regulated (5.7-fold, P = 0.029) in the IVF/ICSI failure group.

CONCLUSION

AZF microdeletions significantly impact male infertility and ART outcomes. High SDF individuals exhibited poorer semen metrics, with 45% AZF microdeletions. These microdeletions altered AZF-associated genes expression, affecting fertility mediator PAWP independently. Dual AZF and SDF screening enables personalized management in severe male infertility, potentially explaining IVF/ICSI failures.

TLR signaling pathway and the effects of main immune cells and epigenetics factors on the diagnosis and treatment of infertility and sterility

Recurrent pregnancy loss (RPL), often known as spontaneous miscarriages occurring two or more times in a row, is a reproductive disease that affects certain couples. The cause of RPL is unknown in many cases, leading to difficulties in therapy and increased psychological suffering in couples. Toll-like receptors (TLR) have been identified as crucial regulators of inflammation in various human tissues. The occurrence of inflammation during parturition indicates that Toll-like receptor activity in tissues related to pregnancy may play a crucial role in the onset and continuation of normal function, as well as in various pregnancy complications like infection-related preterm. TLRs or their signaling molecules may serve as effective therapeutic targets for inhibiting premature activity. At the maternal-fetal interface, TLRs are found in both immune and non-immune cells, such as trophoblasts and decidual cells. TLR expression patterns are influenced by the phases of pregnancy. In this way, translational combinations like epigenetics, have indicated their impact on the TLRs.Importantly, abnormal DNA methylation patterns and histone alterations have an impressive performance in decreasing fertility by influencing gene expression and required molecular and cellular activities which are vital for a normal pregnancy and embryonic process. TLRs, play a central duty in the innate immune system and can regulate epigenetic elements by many different signaling pathways. The potential roles of TLRs in cells, epigenetics factors their ability to identify and react to infections, and their place in the innate immune system will all be covered in this narrative review essay.

Secondary azoospermia after a successful natural pregnancy: a primary prospective study

BACKGROUND

To date, there is a lack of studies conducted on males with secondary azoospermia as a potential cause of male infertility who had previously fathered children through natural conception. The current study aims to investigate the potential causes of secondary azoospermia as a presentation of male infertility as well as the prognostic factors that can impact sperm retrieval rate (SRR) while undergoing microdissection testicular sperm extraction (microTESE).

RESULTS

Thirty two patients were recruited from the andrology outpatient clinic from August 2023 till January 2024. The mean age of the patients was sixty-two years old. All patients had varicoceles. Twenty seven patients (84%) had palpable varicocele grade 2 and 3 on both sides. Further multivariate logistic regression analysis of the significant factors in the univariate regression revealed that younger age (OR 0.7, 95% C.I. 0.7-1.0, p = 0.03) and having a history of coronary artery disease (CAD) were predictable factors for negative TESE outcome (OR 123.1, 95% C.I. 3.2-4748.5, P = 0.01).

CONCLUSION

It appears that the etiopathogenesis of secondary azoospermia are multifactorial. Varicocele and CAD are major factors to be considered. Future studies should be implemented deploying larger pools of patients suffering from the same condition to affirm the findings of this primary study.

A 2-step remote TUNEL approach for sperm DNA fragmentation assessment. Analysis in donors and patients

OBJECTIVES

Infertility is a disease of the male or female reproductive systems. Male reproductive workup is based on routine semen analysis, although of limited value. The 2021 WHO Manual incorporated Sperm DNA Fragmentation (SDF) assessment, and highlighted the need for individual laboratories to define suitable thresholds. This study aimed to present an alternative to address this issue, determine an SDF cut-off value with fertile donors, and characterize SDF in a patient cohort and their relationship with semen parameters.

STUDY DESIGN

A service unit was established to remotely perform TUNEL assay in a 2 step-process. Semen samples were received at andrology laboratories, subjected to routine semen analysis (WHO, 2010), partially processed and transported to the service unit for SDF evaluation. Using this setting, studies were done in fertile donors (n = 15) to define the cut-off value, and in men undergoing infertility workup (n = 318).

RESULTS

A cut-off value of 9.17 % was determined with the fertile donor cohort. With this cut-off, a 64.46 % abnormal SDF incidence was determined in the patient cohort. SDF negatively correlated with sperm number, vitality and motility, and positively with abnormal morphology and male age (P < 0.05). TUNEL-positive cases depicted lower sperm quality and higher male age (P < 0.05). A similar abnormal SDF incidence was determined among patients with semen abnormalities. Asthenozoospermic and ≥40 years patient samples depicted higher (P < 0.05) SDF than those of the general population. SDF incidence was also high in normozoospermic patients.

CONCLUSIONS

Using a 2-step remote approach with a standardized procedure and an SDF cut-off value established with fertile donors, high SDF incidence in semen samples depicting normal and abnormal quality were identified in men consulting for infertility, highlighting the relevance of its evaluation as part of the male fertility workup.

The Correlation of Paternal Age on Semen Parameters in Assisted Reproduction: A Retrospective Study in Qassim, Saudi Arabia

INTRODUCTION

In the past, fertility concerns have predominantly revolved around the effect of a woman's age on the quality of her eggs and the success of her pregnancy. While men generally retain their ability to father children throughout their lives, there is evidence suggesting a decline in natural conception rates as paternal age increases. A growing body of research indicates a potential link between advanced paternal age (APA) and various adverse outcomes, including changes in sperm genetics, reduced conception rates, higher rates of miscarriage, lower live birth rates, and even long-term health consequences in offspring. However, it remains unclear whether there is an association between APA and the effectiveness of assisted reproductive technology (ART). This study aims to shed light on the relationship between APA and semen parameters.

METHODOLOGY

This is a retrospective, descriptive study analyzing data from electronic medical records of men undergoing ART at a fertility clinic in Saudia Arabia (2017-2022). Men aged 21-60 with at least one semen analysis and no missing data/hormonal treatment were included. Data on age and semen parameters (count, motility, and morphology) were extracted and analyzed using Jeffreys's Amazing Statistics Program (JASP; University of Amsterdam, Amsterdam, Netherlands) (descriptive statistics, Spearman's rank correlation).

RESULTS

Analysis of 1506 men undergoing ART revealed a mean age of 37 years (SD=6.94) and a mean sperm count of 55.0 million/mL (SD=46.05). The correlation between age and sperm count indicates a minimal association (r=0.075, p<0.01); moderate positive correlations were observed between sperm count and motility (r=0.406); count and morphology (r=0.543); and motility and morphology (r=0.458).

CONCLUSION

Age may not be a major factor in overall sperm parameters for this population, but a strong positive correlation was observed between sperm count, motility, and normal morphology. These findings suggest that these semen parameters are interconnected, with higher sperm counts potentially indicating better overall sperm quality.

Advanced Paternal Age in Focus: Unraveling Its Influence on Assisted Reproductive Technology Outcomes

As global demographics shift toward increasing paternal age, the realm of assisted reproductive technologies (ARTs), particularly in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), faces new challenges and opportunities. This study provides a comprehensive exploration of the implications of advanced paternal age on ART outcomes. Background research highlights the social, cultural, and economic factors driving men toward later fatherhood, with a focus on the impact of delayed paternity on reproductive outcomes. Methods involve a thorough review of existing literature, centering on changes in testicular function, semen quality, and genetic and epigenetic shifts associated with advancing age. Study results point to intricate associations between the father's age and ART outcomes, with older age being linked to diminished semen quality, potential genetic risks, and varied impacts on embryo quality, implantation rates, and birth outcomes. The conclusions drawn from the current study suggest that while advanced paternal age presents certain risks and challenges, understanding and mitigating these through strategies such as sperm cryopreservation, lifestyle modifications, and preimplantation genetic testing can optimize ART outcomes. Future research directions are identified to further comprehend the epigenetic mechanisms and long-term effects of the older father on offspring health. This study underscores the need for a comprehensive approach in navigating the intricacies of delayed fatherhood within the context of ART, aiming for the best possible outcomes for couples and their children.

Current global status of male reproductive health

BACKGROUND

The widespread interest in male reproductive health (MRH), fueled by emerging evidence, such as the global decline in sperm counts, has intensified concerns about the status of MRH. Consequently, there is a pressing requirement for a strategic, systematic approach to identifying critical questions, collecting pertinent information, and utilizing these data to develop evidence-based strategies. The methods for addressing these questions and the pathways toward their answers will inevitably vary based on the variations in cultural, geopolitical, and health-related contexts. To address these issues, a conjoint ESHRE and Male Reproductive Health Initiative (MRHI) Campus workshop was convened.

OBJECTIVE AND RATIONALE

The three objectives were: first, to assess the current state of MRH around the world; second, to identify some of the key gaps in knowledge; and, third, to examine how MRH stakeholders can collaboratively generate intelligent and effective paths forward.

SEARCH METHODS

Each expert reviewed and summarized the current literature that was subsequently used to provide a comprehensive overview of challenges related to MRH.

OUTCOMES

This narrative report is an overview of the data, opinions, and arguments presented during the workshop. A number of outcomes are presented and can be summarized by the following overarching themes: MRH is a serious global issue and there is a plethora of gaps in our understanding; there is a need for widespread international collaborative networks to undertake multidisciplinary research into fundamental issues, such as lifestyle/environmental exposure studies, and high-quality clinical trials; and there is an urgent requirement for effective strategies to educate young people and the general public to safeguard and improve MRH across diverse population demographics and resources.

LIMITATIONS REASONS FOR CAUTION

This was a workshop where worldwide leading experts from a wide range of disciplines presented and discussed the evidence regarding challenges related to MRH. While each expert summarized the current literature and placed it in context, the data in a number of areas are limited and/or sparse. Equally, important areas for consideration may have been missed. Moreover, there are clear gaps in our knowledge base, which makes some conclusions necessarily speculative and warranting of further study.

WIDER IMPLICATIONS

Poor MRH is a global issue that suffers from low awareness among the public, patients, and heathcare professionals. Addressing this will require a coordinated multidisciplinary approach. Addressing the significant number of knowledge gaps will require policy makers prioritizing MRH and its funding.

STUDY FUNDING/COMPETING INTERESTS

The authors would like to extend their gratitude to ESHRE for providing financial support for the Budapest Campus Workshop, as well as to Microptic S.L. (Barcelona) for kindly sponsoring the workshop. P.B. is the Director of the not-for-profit organization Global Action on Men's Health and receives fees and expenses for his work, (which includes the preparation of this manuscript). Conflicts of interest: C.J.D.J., C.L.R.B., R.A.A., P.B., M.P.C., M.L.E., N.G., N.J., C.K., AAP, M.K.O., S.R.-H., M.H.V.-L.: ESHRE Campus Workshop 2022 (Travel support-personal). C.J.D.J.: Cambridge University Press (book royalties-personal). ESHRE Annual Meeting 2022 and Yale University Panel Meeting 2023 (Travel support-personal). C.L.R.B.: Ferring and IBSA (Lecture), RBMO editor (Honorarium to support travel, etc.), ExSeed and ExScentia (University of Dundee), Bill & Melinda Gates Foundation (for research on contraception). M.P.C.: Previously received funding from pharmaceutical companies for health economic research. The funding was not in relation to this work and had no bearing on the contents of this work. No funding from other sources has been provided in relation to this work (funding was provided to his company Global Market Access Solutions). M.L.E.: Advisor to Ro, Doveras, Next, Hannah, Sandstone. C.K.: European Academy of Andrology (Past president UNPAID), S.K.: CEO of His Turn, a male fertility Diagnostic and Therapeutic company (No payments or profits to date). R.I.M.: www.healthymale.org.au (Australian Government funded not for profit in men's health sector (Employed as Medical Director 0.2 FET), Monash IVF Pty Ltd (Equity holder)). N.J.: Merck (consulting fees), Gedeon Richter (honoraria). S.R.-H.: ESHRE (Travel reimbursements). C.N.: LLC (Nursing educator); COMMIT (Core Outcomes Measures for Infertility Trials) Advisor, meeting attendee, and co-author; COMMA (Core Outcomes in Menopause) Meeting attendee, and co-author; International Federation of Gynecology and Obstetrics (FIGO) Delegate Letters and Sciences; ReproNovo, Advisory board; American Board of Urology Examiner; American Urological Association Journal subsection editor, committee member, guidelines co-author Ferring Scientific trial NexHand Chief Technology Officer, stock ownership Posterity Health Board member, stock ownership. A.P.: Economic and Social Research Council (A collaborator on research grant number ES/W001381/1). Member of an advisory committee for Merck Serono (November 2022), Member of an advisory board for Exceed Health, Speaker fees for educational events organized by Mealis Group; Chairman of the Cryos External Scientific Advisory Committee: All fees associated with this are paid to his former employer The University of Sheffield. Trustee of the Progress Educational Trust (Unpaid). M.K.O.: National Health and Medical Research Council and Australian Research Council (Funding for research of the topic of male fertility), Bill and Melinda Gates Foundation (Funding aimed at the development of male gamete-based contraception), Medical Research Future Fund (Funding aimed at defining the long-term consequences of male infertility). M.H.V.-L.: Department of Sexual and Reproductive Health and Research (SRH)/Human Reproduction Programme (HRP) Research Project Panel RP2/WHO Review Member; MRHI (Core Group Member), COMMIT (member), EGOI (Member); Human Reproduction (Associate Editor), Fertility and Sterility (Editor), AndroLATAM (Founder and Coordinator).

Mediation of association between semen microcystin exposure and semen quality by sex hormones in Chinese men

Numerous studies have shown microcystins (MCs) inducing male reproductive toxicity, but the underlying mechanisms in humans are unclear. Therefore, this study aimed to evaluate the mediating role of serum sex hormones in the association between MC exposure and semen quality. In this study, we measured the levels of semen MCs and serum sex hormones in Chinese men [sample 1 (n = 649); sample 2 (n = 924)]. The results showed that there was a non-significant dose-dependent relationship between semen MCs and semen volume reduction (p for trend = 0.079) in sample 1, and semen MCs were significantly negatively associated with total motility, progressive motility, curvilinear velocity, mean angular displacement and acrosome integrity (p < 0.05) in sample 2. We also found that semen MCs were significantly positively associated with serum follicle stimulating hormone (FSH) (β = 0.151; 95% CI: 0.065, 0.236), but negatively associated with serum inhibin B (INHB) (β = -0.605; 95% CI: -0.944, -0.265), and these linear associations were confirmed in restricted cubic spline (RCS) models (all pnon-linearity > 0.1). Furthermore, mediation analysis revealed that serum INHB mediated 19.86% of the adverse effect of MC exposure on acrosome integrity. In conclusion, this study reveals the mediating roles of serum sex hormones in the relationship between MC exposure and decreased semen quality in men.

Does an increase in adipose tissue 'weight' affect male fertility? A systematic review and meta-analysis based on semen analysis performed using the WHO 2010 criteria

INTRODUCTION

Obesity negatively impact on the metabolism of sex hormones, leading to reduced testosterone serum levels. However, how the obesity could negatively impact on the overall gonadal function, particularly on male fertility, remained unclear so far.

OBJECTIVE

To systematically review evidences regarding the influence of body weight excess on the sperm production.

METHODS

A meta-analysis was conducted, searching all prospective and retrospective observational studies reporting male subjects older than 18 years old, with body weight excess from overweight to severe obesity were considered. Only studies using the V edition of the World Health Organization (WHO) manual for semen analysis interpretation were considered. No specific interventions were considered. Search was focused on studies comparing overweight/obese to normal weight subjects.

RESULTS

Twenty-eight studies were considered. Total sperm count and sperm progressive motility were significantly lower in overweight compared to normal weight subjects. Meta-regression analyses demonstrated that patients' age impacted on sperm parameters. Similarly, obese men showed lower sperm concentration, total sperm number, progressive and total motilities, and normal morphology lower than normal weight subjects. Reduced sperm concentration in obese men was influenced by age, smoking habit, varicocele, and total testosterone serum levels at meta-regression analyses.

CONCLUSIONS

The male potential fertility is reduced in subjects with increased body weight, compared to normal weight men. The higher was the increased body weight, the worst was the sperm quantity/quality. This result comprehensively included obesity among non-communicable risk factor for male infertility, shedding new lights on the negative impact of increased body weight on overall gonadal function.

Clinical management of transgender and non-binary patients in the fertility preservation service: Current evidence

Background: Transgender and non-binary individuals face unique challenges when it comes to fertility preservation (FP). Objective: Despite the growing prevalence of gender dysphoria (GD) and gender transitioning, there is a lack of clear guidelines and consensus on the management of these patients in the FP setting. Clinicians and institutions providing FP services should ensure that they are aware of the needs and circumstances of this underrepresented group of patients and offer them accurate and evidence-based information when counseling and tailoring their FP treatment. Materials and methods: For this scoping review, three major search engines were used. Including Embase, Epistemonikos, Google Scholar, MEDLINE and PubMed. Sources of grey literature were also explored (ResearchGate and Web of Science). The combination of only two keywords [transgender] AND [fertility preservation] was used up to May 2023. Results: The available evidence on clinical management and FP outcomes in transgender patients is limited and mainly originates from case reports or small case series. The main limitation of current FP services for transgender and non-binary individuals is the lack of scientific evidence regarding their care. Discussion: Overall, FP in transgender patients requires individualized and realistic plans, and psychological counseling should be offered. This review aims to provide the latest evidence coming from original studies to facilitate proper counseling and fertility management for these individuals. Conclusions: Inclusive health systems that provide comprehensive reproductive health care to transgender individuals can help them make informed decisions about FP and improve their quality of life. Future research is needed to establish more robust evidence-based guidelines for the management of transgender and non-binary individuals in the FP setting.

Sperm DNA damage: The possible link between obesity and male infertility, an update of the current literature

Obesity prevalence worldwide is increasing significantly. Whilst maternal obesity has clear detrimental impacts on fertility, pregnancy and foetal outcomes, more recently there has been an increasing focus on the role of paternal obesity in human fertility. Recent meta-analyses have indicated that obesity in men negatively affects basic sperm parameters such as sperm count, concentration and motility, increases the incidence of infertility and reduces the chances of conception. Sperm DNA damage, typically characterised by DNA strand breaks and oxidation of DNA nucleotides, is a specialised marker of sperm quality that has been independently associated with recurrent miscarriage, reduced assisted reproduction success and increased mutational loads in subsequent offspring. Whilst, there are still conflicting data in humans as to the association of obesity in men with sperm DNA damage, evidence from rodent models is clear, indicating that male obesity increases sperm DNA damage. Human data are often conflicting because of the large heterogeneity amongst studies, the use of body mass index as the indicator of obesity and the methods used for detection of sperm DNA damage. Furthermore, comorbidities of obesity (i.e., heat stress, adipokines, insulin resistance, changes in lipids, hypogonadism and obstructive sleep apnoea) are also independently associated with increased sperm DNA damage that is not always modified in men with obesity, and as such may provide a causative link to the discrepancies amongst human studies. In this review, we provide an update on the literature regarding the associations between obesity in men and fertility, basic sperm parameters and sperm DNA damage. We further discuss potential reasons for the discrepancies in the literature and outline possible direct and indirect mechanisms of increased sperm DNA damage resulting from obesity. Finally, we summarise intergenerational obesity through the paternal linage and how sperm DNA damage may contribute to the transmission.

Male reproductive ageing: a radical road to ruin

In modern post-transition societies, we are reproducing later and living longer. While the impact of age on female reproductive function has been well studied, much less is known about the intersection of age and male reproduction. Our current understanding is that advancing age brings forth a progressive decline in male fertility accompanied by a reduction in circulating testosterone levels and the appearance of age-dependent reproductive pathologies including benign prostatic hypertrophy and erectile dysfunction. Paternal ageing is also associated with a profound increase in sperm DNA damage, the appearance of multiple epigenetic changes in the germ line and an elevated mutational load in the offspring. The net result of such changes is an increase in the disease burden carried by the progeny of ageing males, including dominant genetic diseases such as Apert syndrome and achondroplasia, as well as neuropsychiatric conditions including autism and spontaneous schizophrenia. The genetic basis of these age-related effects appears to involve two fundamental mechanisms. The first is a positive selection mechanism whereby stem cells containing mutations in a mitogen-activated protein kinase pathway gain a selective advantage over their non-mutant counterparts and exhibit significant clonal expansion with the passage of time. The second is dependent on an age-dependent increase in oxidative stress which impairs the steroidogenic capacity of the Leydig cells, disrupts the ability of Sertoli cells to support the normal differentiation of germ cells, and disrupts the functional and genetic integrity of spermatozoa. Given the central importance of oxidative stress in defining the impact of chronological age on male reproduction, there may be a role for antioxidants in the clinical management of this process. While animal studies are supportive of this strategy, carefully designed clinical trials are now needed if we are to realize the therapeutic potential of this approach in a clinical context.

The Effect of Age on Semen Quality Among Male Partners of Infertile Couples: An Observational Study in a Tertiary Care Center in Eastern India

INTRODUCTION

Male infertility contributes to a significant proportion of infertility cases, and advanced paternal age has been suggested to affect semen quality and fertility. However, the relationship between age and semen quality remains inconclusive, with conflicting findings reported in the literature. This study aimed to investigate the effect of age on semen quality among male partners of infertile couples in a tertiary care center in eastern India.

METHODS

A cross-sectional observational study was conducted, involving 390 male participants aged 21-50 years, who were referred to the andrology laboratory for semen analysis between January 2019 and December 2022. Participants were categorized into three age groups (21-30, 31-40, and 41-50 years). Semen parameters, including sperm concentration, semen volume, motility, and morphology, were assessed according to the World Health Organization guidelines.

RESULTS

Among the participants, no significant differences were observed in semen volume, motility, and morphology across different age groups. However, a statistically significant difference in sperm concentration among the three age groups was observed (p = 0.022). Spearman correlation analysis revealed a positive correlation between age and sperm concentration (r = 0.124, p = 0.013) as well as total sperm count (r = 0.10, p = 0.049).

CONCLUSION

In this study, no significant decline in semen quality with age was found among male partners of infertile couples aged 21-50 years. These findings highlight the complex relationship between age and semen quality and emphasize the need for further research to better understand the underlying mechanisms and provide more conclusive evidence regarding the impact of age on male fertility.

Biomarkers of aging

Aging biomarkers are a combination of biological parameters to (i) assess age-related changes, (ii) track the physiological aging process, and (iii) predict the transition into a pathological status. Although a broad spectrum of aging biomarkers has been developed, their potential uses and limitations remain poorly characterized. An immediate goal of biomarkers is to help us answer the following three fundamental questions in aging research: How old are we? Why do we get old? And how can we age slower? This review aims to address this need. Here, we summarize our current knowledge of biomarkers developed for cellular, organ, and organismal levels of aging, comprising six pillars: physiological characteristics, medical imaging, histological features, cellular alterations, molecular changes, and secretory factors. To fulfill all these requisites, we propose that aging biomarkers should qualify for being specific, systemic, and clinically relevant.

Biallelic variants in IQCN cause sperm flagellar assembly defects and male infertility

STUDY QUESTION

What is the effect of defects in the manchette protein IQ motif-containing N (IQCN) on sperm flagellar assembly?

SUMMARY ANSWER

Deficiency in IQCN causes sperm flagellar assembly defects and male infertility.

WHAT IS KNOWN ALREADY

The manchette is a transient structure that is involved in the shaping of the human spermatid nucleus and protein transport within flagella. Our group recently reported that the manchette protein IQCN is essential for fertilization. Variants in IQCN lead to total fertilization failure and defective acrosome structure phenotypes. However, the function of IQCN in sperm flagellar assembly is still unknown.

STUDY DESIGN, SIZE, DURATION

Fifty men with infertility were recruited from a university-affiliated center from January 2014 to October 2022.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Genomic DNA was extracted from the peripheral blood samples of all 50 individuals for whole-exome sequencing. The ultrastructure of the spermatozoa was assessed by transmission electron microscopy. Computer-assisted sperm analysis (CASA) was used to test the parameters of curvilinear velocity (VCL), straight-line velocity (VSL), and average path velocity (VAP). An Iqcn knockout (Iqcn-/-) mouse model was generated by CRISPR-Cas9 technology to evaluate sperm motility and the ultrastructure of the flagellum. Hyperactivation and sperm fertilizing ability were assessed in a mouse model. Immunoprecipitation followed by liquid chromatography-mass spectrometry was used to detect IQCN-binding proteins. Immunofluorescence was used to validate the localization of IQCN-binding proteins.

MAIN RESULTS AND THE ROLE OF CHANCE

Biallelic variants in IQCN (c.3913A>T and c.3040A>G; c.2453_2454del) were identified in our cohort of infertile men. The sperm from the affected individuals showed an irregular '9 + 2' structure of the flagellum, which resulted in abnormal CASA parameters. Similar phenotypes were observed in Iqcn-/- male mice. VSL, VCL, and VAP in the sperm of Iqcn-/- male mice were significantly lower than those in Iqcn+/+ male mice. Partial peripheral doublet microtubules (DMTs) and outer dense fibers (ODFs) were absent, or a chaotic arrangement of DMTs was observed in the principal piece and end piece of the sperm flagellum. Hyperactivation and IVF ability were impaired in Iqcn-/- male mice. In addition, we investigated the causes of motility defects and identified IQCN-binding proteins including CDC42 and the intraflagellar transport protein families that regulate flagellar assembly during spermiogenesis.

LIMITATIONS, REASONS FOR CAUTION

More cases are needed to demonstrate the relation between IQCN variants and phenotypes.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings expand the genetic and phenotypic spectrum of IQCN variants in causing male infertility, providing a genetic marker for sperm motility deficiency and male infertility.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the National Natural Science Foundation of China (81974230 and 82202053), the Changsha Municipal Natural Science Foundation (kq2202072), the Hunan Provincial Natural Science Foundation (2022JJ40658), and the Scientific Research Foundation of Reproductive and Genetic Hospital of CITIC-Xiangya (YNXM-202114 and YNXM-202201). No conflicts of interest were declared.

TRIAL REGISTRATION NUMBER

N/A.

Fertility in the aging male: a systematic review

The negative effect of advanced female age on fertility and offspring health is well understood. In comparison, much less is known about the implications of male age on fertility, with many studies showing conflicting results. Nevertheless, increasing evidence suggests that advanced paternal age has negative effects on sperm parameters, reproductive success, and offspring health. Herein, we summarize the current body of knowledge on this controversial topic, with the belief that this review will serve as a resource for the clinicians providing fertility counseling to couples with older male partners.

Reproductive axis ageing and fertility in men

Compared to women, increasing male age is not accompanied by such marked changes in reproductive function but changes certainly do happen. These include alterations to the hypothalamo-pituitary-testicular axis, with resultant implications for testosterone production and bioavailability as well as spermatogenesis. There is a decline in sexual function as men age, with a dramatic increase in the prevalence of erectile dysfunction after the age of 40, which is a marker for both clinically evident as well as covert coronary artery disease. Despite a quantitative decline in spermatogenesis and reduced fecundability, the male potential for fertility persists throughout adult life, however there are also increasingly recognised alterations in sperm quality and function with significant implications for offspring health. These changes are relevant to both natural and medically assisted conception.

The future of sperm: a biovariability framework for understanding global sperm count trends

The past 50 years have seen heated debate in the reproductive sciences about global trends in human sperm count. In 2017, Levine and colleagues published the largest and most methodologically rigorous meta-regression analysis to date and reported that average total sperm concentration among men from 'Western' countries has decreased by 59.3% since 1973, with no sign of halting. These results reverberated in the scientific community and in public discussions about men and masculinity in the modern world, in part because of scientists' public-facing claims about the societal implications of the decline of male fertility. We find that existing research follows a set of implicit and explicit assumptions about how to measure and interpret sperm counts, which collectively form what we term the Sperm Count Decline hypothesis (SCD). Using the study by Levine and colleagues, we identify weaknesses and inconsistencies in the SCD, and propose an alternative framework to guide research on sperm count trends: the Sperm Count Biovariability hypothesis (SCB). SCB asserts that sperm count varies within a wide range, much of which can be considered non-pathological and species-typical. Knowledge about the relationship between individual and population sperm count and life-historical and ecological factors is critical to interpreting trends in average sperm counts and their relationships to health and fertility.

Testicular aging, male fertility and beyond

Normal spermatogenesis and sperm function are crucial for male fertility. The effects of healthy testicular aging and testicular premature aging on spermatogenesis, sperm function, and the spermatogenesis microenvironment cannot be ignored. Compared with younger men, the testis of older men tends to have disturbed spermatogenic processes, sperm abnormalities, sperm dysfunction, and impaired Sertoli and Leydig cells, which ultimately results in male infertility. Various exogenous and endogenous factors also contribute to pathological testicular premature aging, such as adverse environmental stressors and gene mutations. Mechanistically, Y-chromosomal microdeletions, increase in telomere length and oxidative stress, accumulation of DNA damage with decreased repair ability, alterations in epigenetic modifications, miRNA and lncRNA expression abnormalities, have been associated with impaired male fertility due to aging. In recent years, the key molecules and signaling pathways that regulate testicular aging and premature aging have been identified, thereby providing new strategies for diagnosis and treatment. This review provides a comprehensive overview of the underlying mechanisms of aging on spermatogenesis. Furthermore, potential rescue measures for reproductive aging have been discussed. Finally, the inadequacy of testicular aging research and future directions for research have been envisaged to aid in the diagnosis and treatment of testicular aging and premature aging.

The impact of male factors and their correct and early diagnosis in the infertile couple's pathway: 2021 perspectives

PURPOSE

The current clinical practice in reproductive medicine should pose the couple at the centre of the diagnostic-therapeutic management of infertility and requires intense collaboration between the andrologist, the gynaecologist and the embryologist. The andrologist, in particular, to adequately support the infertile couple, must undertake important biological, psychological, economical and ethical task. Thus, this paper aims to provide a comprehensive overview of the multifaceted role of the andrologist in the study of male factor infertility.

METHODS

A comprehensive Medline, Embase and Cochrane search was performed including publications between 1969 and 2021.

RESULTS

Available evidence indicates that a careful medical history and physical examination, followed by semen analysis, always represent the basic starting points of the diagnostic work up in male partner of an infertile couple. Regarding treatment, gonadotropins are an effective treatment in case of hypogonadotropic hypogonadism and FSH may be used in men with idiopathic infertility, while evidence supporting other hormonal and nonhormonal treatments is either limited or conflicting. In the future, pharmacogenomics of FSHR and FSHB as well as innovative compounds may be considered to develop new therapeutic strategies in the management of infertility.

CONCLUSION

To provide a high-level of care, the andrologist must face several critical diagnostical and therapeutical steps. Even though ART may be the final and decisive stage of this decisional network, neglecting to treat the male partner may ultimately increase the risks of negative outcome, as well as costs and psychological burden for the couple itself.

Genome-wide methylation analyses of human sperm unravel novel differentially methylated regions in asthenozoospermia

Aims & objectives: To investigate DNA methylation patterns in asthenozoospermic and normozoospermic sperm and to explore the potential roles of differential methylations in the etiology of the disease. Materials & methods: The authors performed whole-genome bisulfite sequencing analysis between normozoospermic controls and asthenozoospermic individuals. Results: The authors identified 238 significant differentially methylated regions. These differentially methylated regions were annotated to 114 protein-coding genes, with many genes showing associations with spermatogenesis, sperm motility etc. Conclusion: There are plenty of genomic regions exhibiting altered DNA methylation in asthenozoospermia, a number of which are located within or adjacent to sperm-related genes, suggesting novel methylation markers of asthenozoospermia and potential epigenetic regulation mechanisms through DNA methylation in the disease.

Age-Dependent Variations in Functional Quality and Proteomic Characteristics of Canine (Canis lupus familiaris) Epididymal Spermatozoa

Increased male age is associated with a significant reduction in semen quality. Little is known about the sperm proteome changes resulting from the aging process. This study aimed to investigate the relationship between the functional quality and proteome of epididymal spermatozoa of dogs that were differing in age. The study was conducted on 30 male dogs that were divided into three age groups. G1—12 to 41 months old, G2—42 to 77 months old, and G3—78 to 132 months old. The sperm samples were assessed using a computer-assisted semen analysis (CASA). The epididymal sperm proteins were analyzed using gel electrophoresis (SDS-PAGE), nano-liquid chromatography coupled to quadrupole time of flight mass spectrometry (NanoUPLC-Q-TOF/MS) and bioinformatic tools. The sperm quality parameters were significantly lower in older dogs. NanoUPLC-Q-TOF/MS identification resulted in 865 proteins that were found in the G1, 472 in G2, and 435 in G3. There were seven proteins that were present in all three age groups, and four of them (ACTB, CE10, NPC2, CRISP2) showed significant changes among the studied groups. Age-dependent variations were detected in the sperm proteome composition and were related to important metabolite pathways, which might suggest that several proteins are implicated in sperm maturation and could be potential aging biomarkers.

Effects of Sleep Disorders and Circadian Rhythm Changes on Male Reproductive Health: A Systematic Review and Meta-analysis

Objectives: The purpose of this study was to elucidate the relationship between sleep disorders and male reproductive health, and to explore the underlying mechanisms via a systematic review and meta-analysis.

Methods: PubMed, Embase, The Cochrane library, Web of Science, Scopus databases were searched to collect clinical research on the effects of sleep disorders on male semen parameters from inception to February 24, 2022. RevMan 5.4 was used for meta-statistical analysis. Stata16 software was used to detect publication bias.

Results: The results of meta-analysis showed that sleep disorders were associated with reduced total sperm count (mean difference (MD) = −27.91, 95% CI = (−37.82, −18.01), p < 0.001), reduced sperm concentration (MD = −5.16, 95% CI = (−9.67, −0.65), p = 0.02), reduced progressive motility (MD = −2.94, 95% CI = (−5.28, −0.59), p = 0.01), and reduced normal morphology (MD = −0.52, 95% CI = (−0.80, −0.24), p < 0.001). However, there is no significant association between sleep disorders and semen volume/reproductive hormones. Further bioinformatics mining revealed that related clock genes (PER1, PER2, CRY2, NR1D1 and NPAS2) were down-regulated in non-obstructive azoospermia patients.

Conclusion: In conclusion, current evidence suggests that sleep disorders have a negative impact on male reproductive health, and its underlying mechanism may be related to circadian rhythm disorders. However, the relationship between sleep disorders and reproductive hormone levels has not been found. Due to the limited number and quality of included studies, the above findings need to be validated by more high-quality studies.

Male infertility and the impact of lifestyle in the Greek population: A case-control study

Background and Aims

Collection of epidemiological data has become a crucial step in every fertility evaluation, especially regarding idiopathic male infertility. Information on data such as tobacco smoking, alcohol intake, and body mass index can provide crucial information regarding the dynamics between fertility status and everyday practices. We aim to set the base for epidemiological studies on male infertility in the Greek population.

Methods

Four hundred and fourteen Greek volunteers were asked to fill in a questionnaire regarding their characteristics and lifestyle preferences, followed by a seminogram. Depending on their answers, they were divided into groups and data were analyzed for correlation with seminogram parameters using Spearman's rank correlation test.

Results

Our results indicate that a high body mass index (BMI) is negatively correlated with all three seminogram parameters (number, motility, and morphology) and exposure to radiation or chemicals is negatively correlated with sperm motility, with a p < 0.01.

Conclusions

These findings indicate negative correlations of BMI and exposure to radiation/chemicals with semen parameters in the Greek population. Such information can be used to plan a diagnostic approach or even therapeutic interventions.

Effect of sexual arousal on semen parameters during abstinence

Semen analysis and physical examination are performed while first evaluation for patients with male infertility. Alcohol, smoking and dietary habits can affect the semen parameters. This study aimed to evaluate whether semen parameters are changed with sexual arousal. After excluding, 100 patients with ages of 18-45 were included to the study. All semen analysis were performed with three days of sexual abstinence. An identified 20 min video link was determined to the patients and while the sexual abstinence were told to watch this video once a day; after 3 days abstinence semen analysis was examined again. In the detailed examination normal spermatozoa ratio (Tygerberg strict criteria), spermatozoa concentration, semen volume, total motility and progressive motility ratios were noted. When the two semen analysis from the same patient are compared, it was observed that all parameters did not change except semen volume and total motile sperm count (p < 0.001). In conclusion, to understand the effect of sexual arousal during the sexual abstinence, we need studies with high patient number and longer follow-up.

Paternal ageing impacts blastulation and the outcomes of pregnancy at different levels of maternal age: A clustering analysis of 21,960 oocytes and 3837 ICSI cycles

The objective of this cross-sectional study was to investigate the impact of paternal age on the outcomes of intracytoplasmic sperm injection (ICSI) cycles at different values of maternal age. A total of 21,960 injected oocytes deriving from 3837 ICSI cycles performed between January 2014 and October 2020, performed in a private university-affiliated in vitro fertilization centre was included. The main effects of maternal and paternal age, as well as the effect of their product (interaction term) on embryo development and pregnancy outcomes were investigated considering the clustering of data. The coefficients for the interaction term were statistically significant for blastocyst development, top-quality blastocyst, implantation, pregnancy, miscarriage, and live-birth rates. For every 1-year increase in paternal age, the odds ratio of live-birth reduces by 1% in females aged 37 years, 1.6% in those aged 38 years, 2.4% in 39-year-old females, 5% in 42-year-old females and so on. An increase in the interaction term by 1 year decreases the pregnancy rate by 0.4% and live-birth rate by 0.8 and increases the miscarriage rate by 1.2%. The slopes of maternal age on blastulation, blastocyst quality, and implantation, pregnancy, miscarriage, and live-birth rate significantly changed (worsened) for every year increase in paternal age.

Management of male factor infertility: position statement from the Italian Society of Andrology and Sexual Medicine (SIAMS) : Endorsing Organization: Italian Society of Embryology, Reproduction, and Research (SIERR)

PURPOSE

Infertility affects 15-20% of couples and male factors are present in about half of the cases. For many aspects related to the diagnostic and therapeutic approach of male factor infertility, there is no general consensus, and the clinical approach is not uniform.

METHODS

In the present document by the Italian Society of Andrology and Sexual Medicine (SIAMS), endorsed by the Italian Society of Embryology, Reproduction, and Research (SIERR), we propose evidence-based recommendations for the diagnosis, treatment, and management of male factor infertility to improve patient and couple care.

RESULTS

Components of the initial evaluation should include at minimum medical history, physical examination, and semen analysis. Semen microbiological examination, endocrine assessment, and imaging are suggested in most men and recommended when specific risk factors for infertility exist or first-step analyses showed abnormalities. Full examination including genetic tests, testicular cytology/histology, or additional tests on sperm is clinically oriented and based on the results of previous investigations. For treatment purposes, the identification of the specific cause and the pathogenetic mechanism is advisable. At least, distinguishing pre-testicular, testicular, and post-testicular forms is essential. Treatment should be couple-oriented, including lifestyle modifications, etiologic therapies, empirical treatments, and ART on the basis of best evidence and with a gradual approach.

CONCLUSION

These Guidelines are based on two principal aspects: they are couple-oriented and place high value in assessing, preventing, and treating risk factors for infertility. These Guidelines also highlighted that male infertility and in particular testicular function might be a mirror of general health of a man.

Pregnancy Achievement by Medical Assisted Reproduction Is Correlated to the G Protein-Coupled Receptor 30 mRNA Abundance in Human Spermatozoa

Estrogens, specifically 17β-estradiol (E2), play an important role in male health, including male fertility. The G protein-coupled receptor for estrogen 30 (GPR30) is essential for mediating the rapid non-genomic effects of E2 on a variety of testicular cells, including spermatozoa, although its molecular effects remain largely unknown. In this work, we hypothesized that the GPR30 mRNA abundance in spermatozoa could be correlated to sperm quality. Sperm GPR30 mRNA could also be carried into the oocyte, potentially impacting embryo development and the success of a pregnancy. For this study, 81 sperm samples were collected from couples seeking fertility treatment and undergoing medically assisted reproduction treatments (ART), following the World Health Organization guidelines. GPR30 mRNA abundance in spermatozoa was assessed with a quantitative polymerase chain reaction. The resulting data show that there is no correlation between the abundance of the GPR30 transcript with paternal BMI, age, or sperm quality parameters. Interestingly, we observed that higher levels of GPR30 mRNA abundance in spermatozoa were related to the achievement of biochemical pregnancy and clinical pregnancy (p < 0.05) by couples undergoing treatment. These results highlight the role of the sperm’s RNA cargo in offspring development, suggesting that spermatozoa mRNA content can influence ART success.

Necrozoospermia: The tree that hides the forest

BACKGROUND

Necrozoospermia is a condition found in 0.2 to 0.4 % of male infertility cases. The causes of necrozoospermia are multiple: they can be related to testicular and/or post-testicular damage. Additionally, these causes most often involve the production of reactive oxygen species (ROS) and/or sperm DNA fragmentation (SDF) which can reduce the chances of spontaneous pregnancy or affect the outcome of assisted reproductive technologies.

OBJECTIVE

To focus on potential etiologies of necrozoospermia, its diagnosis and its therapeutic management especially before the employment of ICSI.

METHODS

Authors searched PubMed/Medline, Web of Science, Cochrane Library, Google and Institutional websites for medical subheading terms and free text words referred to "necrozoospermia", "sperm vitality", "sperm viability", "sperm DNA fragmentation" and "ICSI".

RESULTS

We identified twelve main etiologies of necrozoospermia responsible for either a decrease of sperm vitality, a mild a moderate or a severe necrozoospermia. In case of a confirmed decreased vitality, a thorough check-up should be conducted and if available, etiological treatment should be proposed. Therapeutic management could also include repeated ejaculations, drug treatments, the use of ICSI with ejaculated or surgically extracted spermatozoa in case of a non-treatable necrozoospermia.

DISCUSSION AND CONCLUSION

The potential causes of necrozoospermia should be investigated because many of them could be corrected, thus avoiding the use of ICSI. Moreover, if ICSI procedure remains necessary, the therapeutic management of necrozoospermia could also improve the chances of success by reducing oxidative stress and/or sperm DNA fragmentation. This article is protected by copyright. All rights reserved.

Diet-induced maternal obesity and overnutrition cause a decrease in the sperm quality of the offspring

The present work aimed to study the changes caused by maternal obesity and overnutrition in both the quality and function of spermatozoa of the offspring. To this end, female rats received either a standard (SD) or cafeteria (CD) diet from 22 days of age until the weaning of their offspring, and the male offspring (OSD and OCD respectively) were used. Different endpoints in the offspring, as body weight, weight gain and glycemia were recorded and the testes were removed at 60 days of age. Different spermatozoa parameters, such as mitochondrial function, functional integrity of the sperm plasma membrane, capacitation, and acrosome status, were evaluated. The OCD group was heavier than the OSD group and exhibited lower testis and epididymal indices. The OCD group also showed a decrease in the ability of the sperm tail to react in the presence of a hypoosmotic solution, deficiency in sperm mitochondrial function, a lower percentage of spermatozoa without acrosome when exposed to a capacitation medium, and a higher number of abnormal metaphases. In addition, compared with OSD, OCD rats had a higher number of TUNEL-positive cells in the histological sections of the testis, and greater presence of reactive oxygen species in the spermatozoa, evaluated by a fluorescent probe. However, the OCD group displayed lower protein levels of cytochrome c and caspase-3 in testis tissue than the control group. These results suggest that maternal obesity and overnutrition program the offspring to develop poor sperm quality and function, which may imply a condition of subfertility.

Paternal alcohol consumption has intergenerational consequences in male offspring

PURPOSE

Alcoholism is a heterogeneous set of disorders caused by ethanol intake. Harmful effects of paternal consumption on the offspring are poorly explored and not fully understood. We analyzed the effect of paternal alcohol consumption on both their own reproductive capacity and that of their male offspring.

METHODS

We used a model of ethanol consumption (15% v/v in drinking water) for 12 days in adult CF-1 male mice. DNA integrity and post-translational modifications of histones were assessed in sperm; testicular weight, histology, and DNA fragmentation were analyzed. Treated or untreated male mice were mated with non-treated females to obtain two cell embryos that were cultured for 7 days; morphology and embryonic cell death were evaluated. Males of both groups were mated with non-treated females. Adult male offspring was euthanized, and sperm and testicular parameters determined.

RESULTS

Paternal ethanol consumption caused histological and epigenetic changes, as well as damage in DNA integrity in the testicular germline and sperm. These alterations gave rise to deleterious effects on embryonic development and to testicular and spermatic changes in the offspring.

CONCLUSION

This study provides critical information on reproductive disturbances brought about by paternal alcohol consumption and the profound impact these could have on the male progeny. The need to explore the effects of paternal alcohol consumption in detail and warn about the importance of controlling alcohol intake for the well-being of future generations should not be underscored.

Reprotoxic Impact of Environment, Diet, and Behavior

Reproductive health is progressively declining due to multiples endogenous and exogenous factors, such as environmental contaminants, diet and behavior. Accumulated evidences confirm that fertility and reproductive function have been adversely affected by exposure to chemical contaminants released in the environment. Today, the impact of diet and behavior on reproductive processes is also receiving special attention from the scientific community. Indeed, a close relationship between diet and fertility has been proven. Furthermore, a combination of unhealthy behavior, such as exposure to hazardous compounds and stress factors, poses living organisms at higher risk of reprotoxic effects. In particular, it has been described that poor life behaviors are associated with reduced male and female fertility due to decreased gamete quality and function. Most of the erroneous behaviors are, furthermore, a source of oxidative stress that, leading to epigenetic alterations, results in an impaired reproductive fitness. This review reports the detrimental impact of the most common environmental chemical stressors, diet, and behavior on reproductive functionality and success. Although clear evidences are still scarce, reassuring data are provided that a healthy diet and reverting unhealthy lifestyles may be of help to recover physiological reproductive conditions.

Association of sexually transmitted infection with semen quality in men from couples with primary and secondary infertility

This study aims to compare the prevalence of sexually transmitted infections (STIs) with semen quality in men from couples with primary and secondary infertility. Semen samples were collected from 133 men who requested fertility evaluation. Seminal tract infection with Ureaplasma spp. (UU), Mycoplasma hominis (MH), Mycoplasma genitalium (MG), Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and herpes simplex virus-2 (HSV-2) was assessed by PCR-based diagnostic assays. Among all patients, the prevalence of STIs was higher in men from couples with primary infertility than that in men from couples with secondary infertility (39.7% vs 21.7%, P = 0.03). The prevalence of UU was 28.8% and 13.3% in men from couples with primary and secondary infertility, respectively. Men from couples with primary infertility were more likely to be positive for UU than men from couples with secondary infertility (P = 0.04). Regarding the UU subtype, the prevalence of Ureaplasma urealyticum (Uuu) and Ureaplasma parvum (Uup; including Uup1, Uup3, Uup6, and Uup14) did not differ between the two groups. No associations between the prevalence rates of MH, MG, and CT were found in men from either infertility group. A lower sperm concentration was associated with STI pathogen positivity in men with primary infertility according to the crude model (P = 0.04). The crude and adjusted models showed that semen volume (both P = 0.03) and semen leukocyte count (both P = 0.02) were independently associated with secondary infertility. These findings suggest the importance of classifying the type of infertility during routine diagnosis of seminal tract infections.

Association between meteorological variables and semen quality: a retrospective study

Spermatogenesis is a temperature-dependent process, and high summer temperatures have been linked to lower sperm concentration and count. However, reports describing the association between other meteorological variables and semen quality are scarce. This study evaluated the association between semen quality and temperature, humidity, pressure, apparent temperature (AT), temperature-humidity index (THI), simplified wet-bulb global temperature (sWBGT), and sunshine duration. Semen samples were obtained at the Laboratorio de Andrología y Reproducción (LAR, Argentina), from men undergoing routine andrology examination (n=11657) and computer-assisted sperm analysis (n=4705) following WHO 2010 criteria. Meteorological variables readings were obtained from the Sistema Meteorológico Nacional. Sperm quality parameters were negatively affected in summer when compared to winter. Additionally, there was a significant decrease in sperm kinematics between winter and spring. Branch and bound variable selection followed by multiple regression analysis revealed a significant association between semen quality and meteorological variables. Specifically, changes in sunshine duration and humidity reinforced the prognosis of semen quality. Highest/lowest sunshine duration and humidity quantiles resulted in decreased sperm concentration, count, motility, vitality and membrane competence, nuclear maturity, and sperm kinematics associated to highest sunshine duration and lowest humidity. Findings from this report highlight the relevance of environmental studies for predicting alterations in male reproductive health associated to variations in meteorological variables, especially considering the current climate changes around the planet due to global warming and its consequences for human health.

Reproductive aging and telomeres: Are women and men equally affected?

Successful reproduction is very important for individuals and for society. Currently, the human health span and lifespan are the object of intense and productive investigation with great achievements, compared to the last century. However, reproduction span does not progress concomitantly with lifespan. Reproductive organs age, decreasing the levels of sexual hormones, which are protectors of health through their action on several organs of the body. Thus, this is the starting point of the organismal decay and infertility. This starting point is easily detected in women. In men, it goes under the surface, undetected, but it goes, nevertheless. Regarding fertility, aging alters the hormonal equilibrium, decreases the potential of reproductive organs, diminishes the quality of the gametes and worsen the reproductive outcomes. All these events happen at a different pace and affecting different organs in women and men. The question is what molecular pathways are involved in reproductive aging and if there is a possible halting or even reversion of the aging events. Answers to all these points will be explained in the present review.

Does obesity based on body mass index affect semen quality?-A meta-analysis and systematic review from the general population rather than the infertile population

Whether obesity affects the quality of semen has become the focus of research. However, there are some deficiencies in the past research, because the vast majority of known infertile patients were included in the study samples. Taking infertile men as the research object to analyse the impact of obesity on semen quality, which cannot accurately prove that the impact on semen quality is caused by obesity, because the impact on semen quality may also be caused by other factors. Therefore, we selected ordinary obese men rather than infertile patients to conduct a systematic review and meta-analysis of the effects of obesity on semen parameters. The results showed that obesity had no effect on sperm concentration (SMD: -0.15, 95% CI: -0.32 ~ 0.02, p = .088) and percentage of normal sperm morphology (SMD: -0.17, 95% CI: -0.66 ~ 0.32, p = .487), but decreased semen volume (SMD: -0.32, 95% CI: -0.52 ~ -0.12, p = .002), total sperm number (SMD: -0.77, 95% CI: -1.31 ~ -0.23, p = .005), percentage of forward progression (SMD: -0.95, 95% CI: -1.7 ~ -0.19, p = .014) and percentage of viability (SMD: -0.812, 95% CI: -1.532 ~ -0.093, p = .027). Therefore, obesity affects semen quality to a certain extent, and maintaining normal weight may be one of the effective ways to improve male fertility.

Decline of semen quality over the last 30 years in Uruguay

BACKGROUND

Over the last years, there has been an increasing concern about a global decline in men's fertility. Specifically, some evidence indicates that sperm quality has decreased over the last years. However, reports showing the changes in sperm quality with time are inconsistent. Part of the contradictions between studies is attributed to geographical differences. Surprisingly, few studies include data from South American countries, creating a bias in the conclusions. This study aims to determine how sperm quality has evolved over the past 30 years in Uruguay. For this purpose, 317 medical records from allegedly healthy sperm donor candidates, aged between 18 and 36 years old, who voluntarily requested to be considered as sperm donors between 1988 and 2019, were analyzed. The studied variables were the following sperm parameters: semen volume, sperm cell concentration, total sperm number, progressive motility, vitality, and sperm morphology. A correlative statistical analysis was performed between seminal parameter values and the year data were collected.

RESULTS

We found a statistically significant decrease in sperm concentration and normal sperm morphology during the studied period. There was no decrease in vitality, seminal volume, and total progressive motility. Semen parameters were not associated with tobacco, drugs, or alcohol consumption.

CONCLUSIONS

We conclude that the sperm quality of donor candidates in Uruguay decreased during this period. Further studies should be carried out to verify the occurrence of this phenomenon in the general population and find its possible causes.

Impact of Mitochondrial Genetic Variants in ND1, ND2, ND5, and ND6 Genes on Sperm Motility and Intracytoplasmic Sperm Injection (ICSI) Outcomes

Sperm mitochondrial dysfunction causes the generation of an insufficient amount of energy needed for sperm motility. This will affect sperm fertilization capacity, and thus, most asthenozoospermic men usually require assisted reproductive techniques. The etiology of asthenozoospermia remains largely unknown. The current study aimed to investigate the effect of mitochondrial genetic variants on sperm motility and intracytoplasmic sperm injection (ICSI) outcomes. A total of 150 couples from the ICSI cycle were enrolled in this study. One hundred five of the male partners were asthenozoospermic patients, and they were subdivided into three groups according to their percentage of sperm motility, while forty-five of the male partners were normozoospermic. Genetic variants were screened using direct Sanger's sequencing in four mitochondrial genes (nicotinamide adenine dinucleotide hydrogen (NADH) dehydrogenase 1 (ND1), NADH dehydrogenase 2 (ND2), NADH dehydrogenase 5 (ND5), and NADH dehydrogenase 6 (ND6)). We identified three significant variants: 13708G>A (rs28359178) in ND5, 4216T>C (rs1599988) in ND1, and a novel 12506T>A in ND5 with P values 0.006, 0.036, and 0.013, respectively. The medians of sperm motility, fertilization rate, embryo cleavage score, and embryo quality score were significantly different between men showing 4216T>C, 12506T>A, 13708G>A and wild type, Mann-Whitney P values for the differences in the medians were < 0.05 in all of them. The results from this study suggest that 13708G>A, 12506T>A, and 4216 T>C variants in sperm mitochondrial DNA negatively affect sperm motility and ICSI outcomes.

Protective effects of ginseng stem-leaf saponins on D-galactose-induced reproductive injury in male mice

Panax ginseng is a perennial plant in the Araliaceae family. In this study, we investigated the protective effects of ginseng stem-leaf saponins (GSLS) isolated from P. ginseng against D-galactose-induced reproductive function decline, oxidative stress, and inflammatory response. Reproductive injuries were induced in mice via the subcutaneous injection of D-galactose (300 mg/kg) for six weeks. The mice were then treated with GSLS by intragastric administration. GSLS inhibited markers of oxidative stress and inflammatory cytokines induced by D-galactose in serum, liver and kidney, whereas GSLS increased the activities of antioxidant enzymes. Compared to the mice treated only with D-galactose, GSLS treatment significantly increased the average path velocity, straight line velocity, curvilinear velocity, and amplitude of the lateral head displacement of mouse sperm. Meanwhile, GSLS significantly increased the testosterone level and reduced the cortisol, FSH, and LH levels. Histopathological examination revealed alterations in the number and the arrangement of spermatogenic cells in the seminiferous tubules of the mice in the GSLS group. GSLS treatment suppressed MAPKs pathway activation in testes. These results suggest that GSLS can attenuate D-galactose-induced oxidative stress and inflammatory response in serum, liver and kidney, and ameliorate reproductive damage by inhibiting MAPKs signaling pathway.