Characterization of the Sperm Proteome and Reproductive Outcomes with in Vitro, Fertilization after a Reduction in Male Ejaculatory Abstinence Period

Global Andrology Forum Clinical Guidelines on the Relevance of Sperm DNA Fragmentation in Reproductive Medicine

PURPOSE

To evaluate the evidence on sperm DNA fragmentation (SDF) and its clinical applications in reproductive medicine, highlighting benefits, limitations, and guidelines for its use to assist clinicians in objective decision-making.

MATERIALS AND METHODS

A multidisciplinary team of clinicians and reproductive experts from the Global Andrology Forum (GAF) reviewed the latest evidence on SDF, covering indications, testing methods, recurrent pregnancy loss, varicocele and its repair, assisted reproductive technologies (ART), treatment of associated conditions, antioxidant therapy, and sperm selection for ART. Expert statements and recommendations were developed and graded with the GRADE system using a modified Delphi process.

RESULTS

Based on the GAF surveys, systematic reviews, and meta-analyses related to SDF, 52 experts introduced and scored 24 statements and recommendations using the GRADE system. Of these, 87.5% (21/24) achieved strong ratings, reflecting broad consensus, while 12.5% (3/24) were rated weak. The guidelines provide evidence-based recommendations for clinical scenarios, including the role of SDF in infertility, recurrent pregnancy loss, and ART outcomes.

CONCLUSIONS

While there is growing interest and evidence regarding the clinical benefit of SDF testing and its utility in managing male infertility, significant gaps in the literature limit its routine use in clinical practice. The guidelines offer a structured framework for integrating SDF testing into male infertility management, emphasizing a tailored approach based on individual clinical scenarios. Clinicians must balance the benefits and limitations of SDF testing and antioxidant treatment to optimize care in reproductive medicine. These guidelines are critical for advancing evidence-based practices in male infertility management.

Sperm tRNA-derived fragments expression is potentially linked to abstinence-related improvement of sperm quality

ABSTRACT

Recent studies have shown that shorter periods of ejaculatory abstinence may enhance certain sperm parameters, but the molecular mechanisms underlying these improvements are still unclear. This study explored whether reduced abstinence periods could improve semen quality, particularly for use in assisted reproductive technologies (ART). We analyzed semen samples from men with normal sperm counts (n = 101) and those with low sperm motility or concentration (n = 53) after 3-7 days of abstinence and then after 1-3 h of abstinence, obtained from the Reproductive & Genetic Hospital of CITIC-Xiangya (Changsha, China). Physiological and biochemical sperm parameters were evaluated, and the dynamics of transfer RNA (tRNA)-derived fragments (tRFs) were analyzed using deep RNA sequencing in five consecutive samples from men with normal sperm counts. Our results revealed significant improvement in sperm motility and a decrease in the DNA fragmentation index after the 1- to 3-h abstinence period. Additionally, we identified 245 differentially expressed tRFs, and the mitogen-activated protein kinase (MAPK) signaling pathway was the most enriched. Further investigations showed significant changes in tRF-Lys-TTT and its target gene mitogen-activated protein kinase kinase 2 (MAP2K2), which indicates a role of tRFs in improving sperm function. These findings provide new insights into how shorter abstinence periods influence sperm quality and suggest that tRFs may serve as biomarkers for male fertility. This research highlights the potential for optimizing ART protocols and improving reproductive outcomes through molecular approaches that target sperm function.

The effect of consecutive ejaculation on the sperm parameters in the oligo-astheno-teratozoospermia (OAT) men

Recently, the World Health Organization recommendation for abstinence time for semen analysis has been challenged in some studies and many of them have supported the advantages of a second short abstinence ejaculation. More evidence is needed to approve this for clinical use. This study aimed to compare the average routine abstinence time (2-7 days) with the short time (1-2 h) on sperm quality based on functional parameters in a population of oligo-astheno-teratozoospermia (OAT) men. The semen samples were retrieved from 50 men with OAT two times: one standard 2-7 days (long ejaculation) and short duration trimming (1-2 hours later the first ejaculation). All semen parameters as well as sperm DNA integrity were compared between groups. Results showed that mean sperm concentration (10.40 vs. 8.76), total sperm count (28.53 vs. 12.24) and mean semen volume (2.69 vs. 1.40) were higher in the first ejaculation (2-7 days of abstinence), while progressive motility (20.52 vs. 13.32), non-progressive motility (53.46 vs. 48.86), morphology (2.46 vs. 1.46) and viability (83.90 vs. 77.96) were significantly higher in the second ejaculation (P < 0.05). The second sample also showed lower immotile (26.82 vs. 38.02) and DNA fragmentation (19.5 vs. 26.96) (P < 0.05). Taking all data into account, an additional short abstinence period (AP) may be a simple and helpful strategy to obtain better sperm quality in couples with male infertility causes, especially in OAT patients. The recommended current guidelines regarding the AP may need to be revisited in severe male factors.

Impact of short abstinence versus testicular sperm on sperm DNA fragmentation: a systematic review and meta-analysis

PURPOSE

Optimal sperm DNA integrity is essential for fertilization and embryo health. Research indicates that testicular sperm (TS), obtained via TESA or TESE, typically show lower sperm DNA fragmentation (SDF) than ejaculated sperm after standard abstinence. Shortening abstinence to less than 2 days might reduce SDF, offering a less invasive and more cost-effective alternative to surgical sperm retrieval. Yet, no studies have directly compared the efficacy of shorter abstinence against TS extraction for lowering SDF. Our meta-analysis aims to address this gap by comparing SDF levels in TS to those in ejaculated sperm after a short abstinence period.

METHODS

Meta-analysis of 16 randomized controlled and prospective observational studies included 4 on TS and 12 on short abstinence ejaculation. The meta-analysis followed MOOSE guidelines, scrutinizing databases including Cochrane Library, Web of Science, Embase, MEDLINE(R), and PUMBED up to November 16, 2023. The analysis was conducted using RevMan. The observational studies' methodological quality was assessed using the Newcastle-Ottawa Scale, and the overall evidence quality was evaluated following the GRADE criteria. To compare short ejaculation duration and TS (are not directly compared in the literature) for SDF levels, we analyzed relevant data from studies of each method. We adjusted the participant numbers in the TS group by 1/3 and included each TS study three times, to perform a comparison against the short duration studies which were in a ratio of 1:3. This approach maintained an unaltered cumulative subject count for the meta-analysis of TS studies.

RESULTS

A total of 641 patients were included, comprising 120 and 521 patients with SDF measurements following TS and ejaculation after a short abstinence period, respectively. The studies had varied inclusion criteria, with not all patients having an initial elevated SDF. Some studies had incomplete details on age and other demographics. However, the mean ± SD age of 93 TS patients was 38.15 ± 5.48 years vs. 37.7 ± 6.0 years of 444 short abstinence patients, demonstrating no significant difference (P = 0.544). Short abstinence durations ranged from 1 to 48 h. Diverse DNA fragmentation tests were used: TUNEL assay in three testicular sperm studies, SCD assay in one, and in the short abstinence group, four used TUNEL and six used SCD assays, along with one each using SCSA and Halosperm. The mean ± SD SDF was lower in the TS group than in the short abstinence group (mean difference - 9.48, 95%CI - 12.45 to - 6.52, P < 0.001, I2 = 85%). Sensitivity analysis revealed that no single study significantly influenced the results. Employing the GRADE criteria, the initial assessment categorized the overall quality of evidence as low due to the observational nature of the acquired data. All studies were of medium to high quality.

CONCLUSION

This study suggests testicular sperm may be better than ejaculated sperm for improving SDF in infertility cases. Direct comparisons are needed, before deeming short abstinence less effective. Future research should directly compare reproductive outcomes using both methods.

Impact of Shorter Abstinence Periods on Semen Parameters: A Systematic Review and Meta-Analysis

PURPOSE

The success of assisted reproductive technology (ART) relies heavily on semen parameters, and it is influenced by the length of the abstinence period. The World Health Organization (WHO) recommends a 2- to 7-day abstinence period. Even so, efficacy is still suboptimal. Thus, this study aims to determine whether shorter abstinence periods (<2 days) can improve semen parameters.

MATERIALS AND METHODS

This study is a systematic review and meta-analysis. A literature search was performed across five databases: PubMed, Embase, ProQuest, Scopus, and Wiley Online Library using the PICO format. Retrieved articles were assessed according to eligibility criteria and the PRISMA flow diagram. Those eligible for quantitative analysis were assessed using forest plots. Risks of bias were tested using the Newcastle-Ottawa Scale.

RESULTS

A total of 22 studies and 31,640 samples were included. Studies showed that short abstinence periods significantly reduced semen volume (mean difference [MD] -0.83, p<0.01), sperm concentration (MD -8.39, p<0.01), and DNA fragmentation (MD -3.82, p<0.01). No differences in sperm morphology were identified. Meanwhile, the overall effect for total (MD 2.30, p<0.05) and progressive motile sperm (MD 2.18, p<0.01) was significantly increased. Subgroup analysis on oligospermia patients revealed a significant increase in normal sperm morphology (MD 1.64, p<0.01) along with reduced DNA fragmentation (MD -3.30, p<0.05). However, no significant changes were seen among other sperm parameters.

CONCLUSIONS

In conclusion, our findings suggest a shorter abstinence period could be beneficial due to its effect on sperm motility and DNA fragmentation. Additionally, oligospermia patients will benefit from improved sperm morphology. These findings can provide insight for future guidelines to promote a shorter abstinence period for improving ART outcomes.

Association of abstinence time with semen quality and fertility outcomes: a systematic review and dose-response meta-analysis

BACKGROUND

Infertility affects 186 million people worldwide, with male factors contributing to 50% of infertility cases. Semen analysis is a key for diagnosing male factor infertility, but sperm parameters can be influenced by ejaculatory abstinence (EA) duration. Shortening or prolonging EA can impact on semen quality and assisted reproductive technology (ART) outcomes, but the optimal EA duration remains unclear, particularly for infertility patients.

OBJECTIVES

This study conducts a comprehensive meta-analysis to explore the impact of varying abstinence durations on semen quality and fertility outcomes.

METHODS

Three English database (PubMed, Embase, and Cochrane Central Register of Controlled Trials) as well as four Chinese database (China National Knowledge Infrastructure, Chinese Scientific Journals database, WanFang database, and Chinese Biomedical Literature database) were searched from 2000 to August 2023. The classical meta-analysis and "one-stage" dose-response meta-analysis were conducted to compare the associations of different abstinence durations (short-term abstinence vs. long-term abstinence) on semen quality in healthy adult and different type of infertile patients.

RESULTS

There were 85 eligible studies were finally included. The meta-analysis of volume (mean difference [MD] = -0.95 mL, 95% confidence interval [CI]: -1.16 to -0.74 mL), total sperm count (TSC) (MD = -102.45×106, 95% CI: -117.98×106 to -86.91×106), sperm concentration (SC) (MD = -11.88×106/mL, 95% CI: -18.96×106/mL to -4.80×106/mL), DNA fragmentation index (DFI) (MD = -2.37%, 95% CI: -4.73% to -0.01%) in healthy men showed a significant decrease with different abstinence durations (short-term abstinence vs. long-term abstinence). The meta-analysis of infertile men showed significant decrease in volume in various subgroups (MD range: -0.73 to -1.17 mL) with P < 0.01; TSC (MD = -61.93×106, 95% CI: -88.84×106 to -35.01×106), SC (MD = -5.39×106/mL, 95% CI: -9.97×106 to -0.81×106/mL), DFI (MD = -5.63%, 95% CI: -10.19% to -1.06%) in unexplained infertility subgroup; significant increase in viability (MD = 6.14%, 95% CI: 3.61% to 8.68%) in the unexplained infertility subgroup. The dose-response meta-analysis showed that TSC in oligozoospermia showed a nonlinear increase (coefficient from 3.38 to -5.76, P from 0.02 to 0.22) and the truncation point was around the 4th to 5th abstinence day. The percentage of progressive motile sperm (PR) in asthenozoospermia showed a significant decrease (coefficient = -2.39, 95% CI: -4.28 to -0.50). For fertility outcomes of different ARTs, only the clinical pregnancy rate (CPR) in the intrauterine insemination (IUI) subgroup showed a significant decrease around the 3rd day (coefficient = 0.85, 95% CI: 0.75 to 0.97).

CONCLUSIONS

Short-term abstinence may be associated with limited improvements in semen quality in healthy men but could be more beneficial for infertile men, especially within the first 4 days of abstinence. Caution is urged in making definitive conclusions about the causal relationship between abstinence time and semen quality changes due to potential confounding and interactions.

Abstinence for sperm sample collection and ART outcome: an unsubstantiated myth

PURPOSE OF REVIEW

Semen analysis is a basic component of male evaluation. Reproductive centers typically instruct men to provide a semen specimen based on recommendations from WHO Standard for semen examination. Evidence that these recommendations optimize sperm reproductive capacity is lacking. Existing data to optimize sperm quality with shorter abstinence were reviewed.

RECENT FINDINGS

Several recent studies have reviewed the effects of shorter ejaculatory abstinence of semen quality and assisted reproductive technology (ART) outcomes. Shorter abstinence was defined as 1 h-1 day in one review, and <4 h in the other systematic meta-analysis and review.

SUMMARY

Prior instructions for male patients have not been designed to optimize fertility potential for semen analyses. Optimal sperm quality is obtained by instructing men to have a short abstinence (certainly <1 day, and preferably <4 h) for semen specimens used for in vitro fertilization (assisted reproduction).

Substrate and Functional Diversity of Protein Lysine Post-translational Modifications

Lysine post-translational modifications (PTMs) are widespread and versatile protein PTMs that are involved in diverse biological processes by regulating the fundamental functions of histone and non-histone proteins. Dysregulation of lysine PTMs is implicated in many diseases, and targeting lysine PTM regulatory factors, including writers, erasers, and readers, has become an effective strategy for disease therapy. The continuing development of mass spectrometry (MS) technologies coupled with antibody-based affinity enrichment technologies greatly promotes the discovery and decoding of PTMs. The global characterization of lysine PTMs is crucial for deciphering the regulatory networks, molecular functions, and mechanisms of action of lysine PTMs. In this review, we focus on lysine PTMs, and provide a summary of the regulatory enzymes of diverse lysine PTMs and the proteomics advances in lysine PTMs by MS technologies. We also discuss the types and biological functions of lysine PTM crosstalks on histone and non-histone proteins and current druggable targets of lysine PTM regulatory factors for disease therapy.

The Association between Abstinence Period and Semen Parameters in Humans: Results in Normal Samples and Different Sperm Pathology

BACKGROUND

The impact of sexual abstinence on sperm quality, particularly in pathological cases, is a subject of debate. We investigated the link between abstinence duration and semen quality in both normal and pathological samples.

METHODS

We analyzed semen samples from 4423 men undergoing fertility evaluation, comprising 1256 samples from healthy individuals and 3167 from those with conditions such as oligozoospermia, asthenozoospermia, teratozoospermia, or a combination of these factors, namely oligoasthenoteratozoospermia (OAT). Parameters including sperm concentration, the percentage of progressively motile spermatozoa, total motile sperm count, and the percentage of spermatozoa with normal morphology were assessed at various abstinence durations (each day, 0-2, 3-7, and >7 days).

RESULTS

Extended abstinence correlated with higher sperm concentration overall (p < 0.001), except in oligozoospermia. Longer abstinence reduced progressive motility in normal (p < 0.001) and teratozoospermic samples (p < 0.001). Shorter abstinence was linked to higher morphologically normal sperm in normal samples (p = 0.03), while longer abstinence did so in oligoasthenoteratozoospermic samples (p = 0.013).

CONCLUSION

The findings suggest that a prolonged abstinence time is linked to higher sperm concentration, while optimal sperm motility is observed after shorter abstinence periods. However, results regarding morphology remain inconclusive. Recommendations on abstinence duration should be tailored based on the specific parameter requiring the most significant improvement.

GlycoTCFM: Glycoproteomics Based on Two Complementary Fragmentation Methods Reveals Distinctive O-Glycosylation in Human Sperm and Seminal Plasma

Human semen, consisting of spermatozoa (sperm) and seminal plasma, represents a special clinical sample type in human body fluid. Protein glycosylation in sperm and seminal plasma plays key roles in spermatogenesis, maturation, capacitation, sperm-egg recognition, motility of sperm, and fertilization. In this study, we profiled the most comprehensive O-glycoproteome map of human sperm and seminal plasma using our recently presented Glycoproteomics based on Two Complementary Fragmentation Methods (GlycoTCFM). We showed that sperm and seminal plasma contain many novel and distinctive O-glycoproteins, which are mostly located in the extracellular region (seminal plasma) and sperm membrane, enriched in the biological processes of cell adhesion and angiogenesis, and mainly involved in multiple biological functions including extracellular matrix structural constituents and binding. Based on GlycoTCFM, we created a comprehensive human sperm and seminal plasma O-glycoprotein database that contains 371 intact O-glycopeptides and 202 O-glycosites from 68 O-glycoproteins. Interestingly, 105 manually confirmed O-glycosites from 25 O-glycoproteins were reported for the first time, and they were mainly modified by core 1 O-glycans. We also found that three highly abundant, highly complex, and highly O-glycosylated proteins (semenogelin-1, semenogelin-2, and equatorin) may play important roles in sperm or seminal plasma composition and function. These data deepen our knowledge about O-glycosylation in sperm and seminal plasma and lay the foundation for the functional study of O-glycoproteins in male infertility.

Improved sperm DNA fragmentation levels in infertile men following very short abstinence of 3-4 hours

Background

Limited data exists on possible approaches to improve sperm DNA fragmentation index (DFI) when no identifiable cause is found. The effect of short abstinence on sperm parameters has been extensively studied, but rarely reported on the effect on DFI in infertile men. In this study, we aimed to determine whether a second ejaculate provided after very short abstinence demonstrates lower DFI rates in infertile men.

Methods

This prospective cohort study was conducted at Mount Sinai Hospital, Toronto, Canada, a tertiary university affiliated hospital. All men having DFI testing in addition to the standard semen analysis were identified via a prospectively collected database. Infertile men were instructed to provide two semen samples 3-4 hours apart (the first sample was given after 2-5 days of abstinence) to test the effect on DFI levels. Data analysis was performed for the comparison of the change in sperm parameters and DFI between samples and between men with DFI above and under 30%.

Results

A total of 52 men provided double ejaculates 3-4 hours apart. In the entire group, DFI decreased from 38.9%±21.4% to 35.1%±21.6% in the second sample (P<0.001). Semen volume was lower on the second sample (2.3±1.4 vs. 1.5±0.9 mL, P<0.001), while the remaining parameters did not change. Forty out of 52 patients (76.9%) had improved DFI (average of 6.0±4.0 percentage points). Change in DFI varied with 22/52 (42.3%) and 7/52 (13.5%) of patients found to have decreases in DFI >5% and >10% in the second ejaculate, respectively. For men with DFI of 30-40%, 64% (7/11) of DFIs reduced to the under 30% range. First DFI value was the only parameter associated with DFI decrease to under 30% in multivariate models [odds ratio (OR), 0.62; 95% confidence interval (CI): 0.39-0.98; P=0.04].

Conclusions

This study identified significant improvements in DFI in infertile men providing a second sample after 3-4 hours. Controlled trials are needed to determine if reproductive outcomes are improved using a second ejaculate for infertile men with high initial sperm DFI values.

Controversy and Consensus on the Management of Elevated Sperm DNA Fragmentation in Male Infertility: A Global Survey, Current Guidelines, and Expert Recommendations

PURPOSE

Sperm DNA fragmentation (SDF) has been associated with male infertility and poor outcomes of assisted reproductive technology (ART). The purpose of this study was to investigate global practices related to the management of elevated SDF in infertile men, summarize the relevant professional society recommendations, and provide expert recommendations for managing this condition.

MATERIALS AND METHODS

An online global survey on clinical practices related to SDF was disseminated to reproductive clinicians, according to the CHERRIES checklist criteria. Management protocols for various conditions associated with SDF were captured and compared to the relevant recommendations in professional society guidelines and the appropriate available evidence. Expert recommendations and consensus on the management of infertile men with elevated SDF were then formulated and adapted using the Delphi method.

RESULTS

A total of 436 experts from 55 different countries submitted responses. As an initial approach, 79.1% of reproductive experts recommend lifestyle modifications for infertile men with elevated SDF, and 76.9% prescribe empiric antioxidants. Regarding antioxidant duration, 39.3% recommend 4-6 months and 38.1% recommend 3 months. For men with unexplained or idiopathic infertility, and couples experiencing recurrent miscarriages associated with elevated SDF, most respondents refer to ART 6 months after failure of conservative and empiric medical management. Infertile men with clinical varicocele, normal conventional semen parameters, and elevated SDF are offered varicocele repair immediately after diagnosis by 31.4%, and after failure of antioxidants and conservative measures by 40.9%. Sperm selection techniques and testicular sperm extraction are also management options for couples undergoing ART. For most questions, heterogenous practices were demonstrated.

CONCLUSIONS

This paper presents the results of a large global survey on the management of infertile men with elevated SDF and reveals a lack of consensus among clinicians. Furthermore, it demonstrates the scarcity of professional society guidelines in this regard and attempts to highlight the relevant evidence. Expert recommendations are proposed to help guide clinicians.

Short-interval second ejaculation improves sperm quality, blastocyst formation in oligoasthenozoospermic males in ICSI cycles: a time-lapse sibling oocytes study

Background

Does short-interval second ejaculation improve sperm quality, embryo development and clinical outcomes for oligoasthenozoospermia males received intracytoplasmic sperm injection (ICSI) treatment?

Methods

All enrolled male patients underwent short-interval secondary ejaculation on the day of oocyte retrieval, and 786 sibling MII oocytes from 67 cycles were equally divided into two groups based on whether the injected spermatozoons originated from the first or second ejaculation. Semen parameters, embryo development efficiency, morphokinetic parameters and clinical outcomes were compared between the two groups to assess the efficiency and clinical value of short-interval second ejaculation in ICSI cycles.

Results

Short-interval second ejaculation significantly improved sperm motility, normal morphological rate, and sperm DNA integrity both before and after sperm swim-up. The high-quality blastocyst rate (24.79% versus 14.67%), available blastocyst rate (57.56% versus 48.44%), and oocyte utilization rate (52.93% versus 45.29%) were significantly higher in the second ejaculation group (P<0.05). The clinical pregnancy rate (59.09% versus 47.37%), implantation rate (42.11% versus 32.35%) and live birth rate (40.91% versus 31.58%) were higher in the second ejaculation group, but the differences were not significant (P>0.05). Time-lapse analysis showed that morphokinetic time points after the 7-cell stage were earlier in the second ejaculation group but without a significant difference (P>0.05), and abnormal embryo cleavage patterns between the two groups were not significantly different (P>0.05).

Conclusions

Short-interval second ejaculation significantly improves sperm quality in oligoasthenozoospermic males, and is beneficial for blastocyst formation efficiency in ICSI cycles. This study suggested a non-invasive and simple but effective strategy for improving ICSI treatment outcomes.

Mapping the human sperm proteome - novel insights into reproductive research

INTRODUCTION

Spermatozoa are highly specialized cells with unique morphology. In addition, spermatozoa lose a considerable amount of cytoplasm during spermiogenesis, when they also compact their DNA, resulting in a transcriptionally quiescent cell. Throughout the male reproductive tract, sperm will acquire proteins that enable them to interact with the female reproductive tract. After ejaculation, proteins undergo post-translational modifications for sperm to capacitate, hyperactivate and fertilize the oocyte. Many proteins have been identified as predictors of male infertility, and also investigated in diseases that compromise reproductive potential.

AREAS COVERED

In this review we proposed to summarize the recent findings about the sperm proteome and how they affect sperm structure, function, and fertility. A literature search was performed using PubMed and Google Scholar databases within the past 5 years until August 2022.

EXPERT OPINION

Sperm function depends on protein abundance, conformation, and PTMs; understanding the sperm proteome may help to identify pathways essential to fertility, even making it possible to unravel the mechanisms involved in idiopathic infertility. In addition, proteomics evaluation offers knowledge regarding alterations that compromise the male reproductive potential.

The Impact of a Very Short Abstinence Period on Assisted Reproductive Technique Outcomes: A Systematic Review and Meta-Analysis

BACKGROUND

Previous studies supported the beneficial effects of a very short abstinence period on sperm quality. This systematic review and meta-analysis aimed to evaluate the effects of a very short abstinence period (within 4 h) on assisted reproductive technique (ART) outcomes.

METHODS

A literature search was performed using the Pubmed, Scopus, Web of Science, and Cochrane databases. A meta-analysis was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) for randomized controlled trials (RCTs). All eligible studies were selected following the PICOS (Population, Intervention, Comparison/Comparator, Outcomes, Study type) model. The following pregnancy outcomes after ART were considered: fertilization rate (FR), implantation rate (IR), clinical pregnancy rate (CPR), live birth rate (LBR), and miscarriage rate (MR). This study was registered on PROSPERO (CRD42023396429).

RESULTS

We evaluated 414 records for eligibility, and 7 studies were ultimately included. Our analysis showed that a very short abstinence period significantly increased the IR, CPR, and LBR after ART. No significant differences were found for the FR and MR.

CONCLUSIONS

A second ejaculation collected very shortly after the first one could represent a simple strategy to improve the results of ART, especially in couples including patients with abnormal sperm parameters.

The Influence of Male Ejaculatory Abstinence Time on Pregnancy Rate, Live Birth Rate and DNA Fragmentation: A Systematic Review

Variation in ejaculatory abstinence time and its influence on semen quality and clinical reproductive outcomes is a growing concern among clinicians and researchers. The WHO (World Health Organization) recommends 2–7 days of abstinence time prior to semen collection for diagnostic purposes; however, the evidence that such an abstinence period leads to better pregnancy outcomes remains unclear. The aim of this systematic review is to evaluate short and long ejaculatory abstinence time in association with pregnancy rate, live birth rate and DNA fragmentation, in order to make a recommendation on an ideal timeframe for ejaculatory abstinence. This review is conducted according to the PRISMA guidelines and registered in PROSPERO (CRD42022379039). The electronic databases PubMed, Embase and Cochrane were searched for eligible studies. The Scottish Intercollegiate Guidelines Network was used for the assessment of the risk of bias across the included studies. Twenty-four studies were included in this systematic review. The included studies confirm that a shorter abstinence time is associated with improved pregnancy rates and live birth rates following assisted reproductive technology compared with longer ejaculatory abstinence times at different cut-off points. Similarly, a lower DNA fragmentation index was reported in semen analyses collected from short abstinence times compared with long abstinence times. However, due to the heterogeneity of the included studies, it is not possible to extract an ideal time of ejaculatory abstinence, but all outcomes improved with shorter ejaculatory abstinence times. This systematic review confirms that short ejaculatory abstinence times, less than those recommended by the WHO for diagnostic purposes, are associated with higher pregnancy and live birth rates and improved DNA fragmentation, when compared to long ejaculatory abstinence times.

Identification of selection signatures in Capra hircus and Capra aegagrus in Iran

Identification of selection signatures may provide a better understanding of domestication process and candidate genes contributing to this process. In this study, two populations of domestic and wild goats from Iran were analyzed to identify selection signatures. RSB, iHS, and XP-EHH statistics were used in order to identify robust selection signatures in the goat genome. Genotype data of domestic and wild goats from the NextGen project was used. The data was related to 18 Capra aegagrus (wild goat) and 20 Capra hircus (domestic goat) from Iran. The iHS method indicated 675 and 441 selection signatures in C. aegagrus and C. hircus, respectively. RSB and XP-EHH methods showed about 370 and 447 selection signatures in C. aegagrus and C. hircus, respectively. These selection signatures were mainly associated with milk production, fleece trait, mammary epithelial cells, reproduction, and immune system.

Blood trihalomethane concentrations in relation to sperm mitochondrial DNA copy number and telomere length among 958 healthy men

BACKGROUND

In animal and human studies, exposure to trihalomethanes (THMs) has been associated with reduced semen quality. However, the underlying mechanisms remain poorly understood.

OBJECTIVE

To investigate the associations of blood THM concentrations with sperm mitochondrial DNA copy number (mtDNAcn) and telomere length (TL) among healthy men.

METHODS

We recruited 958 men who volunteered as potential sperm donors. A single blood sample was collected from each participant at recruitment and measured for chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM) concentrations. Within a 90-day follow-up, the last semen sample provided by each participant was quantified for sperm mtDNAcn and TL. We used multivariable linear regression models to assess the associations between blood THM concentrations and sperm mtDNAcn and TL. We also performed stratified analyses according to the time intervals between baseline blood THM determinations and semen collection (i.e., 0-9, 10-14, 15-69, or >69 days) to explore potential windows of susceptibility.

RESULTS

After adjusting for potential confounders, we found inverse associations between quartiles (or categories) of blood TBM, brominated THM (Br-THM, the sum of BDCM, DBCM, and TBM), and total THM (TTHM, the sum of all four THMs) concentrations and sperm mtDNAcn (all P for trend≤0.03). Besides, we found inverse associations between quartiles of blood TCM, Br-THM, chlorinated THM (Cl-THM, the sum of TCM, BDCM, and DBCM), and TTHM concentrations and sperm TL (all P for trend<0.10). Stratified analyses showed stronger associations between Br-THM concentrations and sperm mtDNAcn determined 15-69 days since baseline exposure determinations, and between blood TCM and TTHM concentrations and sperm TL determined >69 days since baseline exposure determinations.

CONCLUSION

Exposure to THMs may be associated with sperm mitochondrial and telomeric dysfunction.

Proteomic Landscape of Human Spermatozoa: Optimized Extraction Method and Application

Human spermatozoa proteomics exposed to some physical, biological or chemical stressors is being explored. However, there is a lack of optimized sample preparation methods to achieve in-depth protein coverage for sperm cells. Meanwhile, it is not clear whether antibiotics can regulate proteins to affect sperm quality. Here, we systematically compared a total of six different protein extraction methods based the combination of three commonly used lysis buffers and physical lysis strategies. The urea buffer combined with ultrasonication (UA-ultrasonication) produced the highest protein extraction rate, leading to the deepest coverage of human sperm proteome (5685 protein groups) from healthy human sperm samples. Since the antibiotics, amoxicillin and clarithromycin, have been widely used against H. pylori infection, we conduct a longitudinal study of sperm proteome via data-independent acquisition tandem mass spectrometry (DIA-MS/MS) on an infected patient during on and off therapy with these two drugs. The semen examination and morphological analysis were performed combined with proteomics analysis. Our results indicated that antibiotics may cause an increase in the sperm concentration and the rate of malformed sperm and disrupt proteome expression in sperm. This work provides an optimized extraction method to characterize the in-depth human sperm proteome and to extend its clinical applications.

The Impact of a Very Short Abstinence Period on Conventional Sperm Parameters and Sperm DNA Fragmentation: A Systematic Review and Meta-Analysis

PURPOSE

In recent years, a growing number of studies have supported the beneficial effects of a very short abstinence period on sperm parameters, especially in patients with oligoasthenozoospermia. However, the results are controversial and no consensus exists regarding whether to request a second semen collection in clinical practice. Therefore, this systematic review and meta-analysis aimed to evaluate the influence of a very short abstinence period (within 4 h) on conventional sperm parameters and sperm DNA fragmentation (SDF) rate.

MATERIALS AND METHODS

The literature search was performed using Scopus and PubMed databases. The meta-analysis was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol (PRISMA-P) guidelines. All eligible studies were selected according to the Population, Intervention, Comparison/Comparator, Outcomes, and Study design (PICOS) model. The quality of evidence of the included studies was analyzed through the Cambridge Quality Checklists. The standardized mean difference (SMD) was used to analyze the outcomes. Cochran-Q and I² statistics were used to evaluate statistical heterogeneity.

RESULTS

We assessed for eligibility 1334 abstracts, and 19 studies were finally included. All 19 articles evaluated the effects of a very short abstinence period on sperm parameters and, among these, 5 articles also evaluated the effects on SDF rate. The quantitative analysis showed a significant reduction in semen volume after a very short abstinence period in both normozoospermic men and patients with oligozoospermia, asthenozoospermia, and/or teratozoospermia (OAT) patients. We found a statistically significant increase in sperm concentration and total and progressive motility in the second ejaculation of patients with OAT. In contrast, the SDF rate decreased significantly in the second ejaculate of OAT patients.

CONCLUSIONS

This is the first systematic review and meta-analysis investigating the impact of a very short abstinence period on sperm parameters and SDF rate. The results suggest that collecting a second consecutive ejaculation after a very short time from the first could represent a simple and useful strategy for obtaining better-quality spermatozoa, especially in patients with abnormal sperm parameters.

Longitudinal semen parameter assessments and live birth: variability and implications for treatment strategies

OBJECTIVE

To examine whether semen parameters are associated with live birth among couples seeking infertility treatment after accounting for semen parameter variability.

DESIGN

Folic Acid and Zinc Supplementation Trial (FAZST) prospective cohort.

SETTING

Four US reproductive endocrinology and infertility care study centers, 2013-2017.

PATIENT(S)

Couples (n = 2,369) seeking fertility consultations at 4 US infertility care study centers.

INTERVENTION(S)

Semen volume, pH, sperm viability, morphology, progressive and total motility, concentration, count, and total and progressive motile count assessed at baseline and at 2, 4, and 6 months after enrollment.

MAIN OUTCOME MEASURE(S)

Log-binomial models stratified by fertility treatment received (in vitro fertilization [IVF], intrauterine insemination [IUI], ovulation induction [OI], or no treatment) estimated risk differences (RDs) between semen parameter quartiles and live birth and accounted for multiple semen assessments per person. We accounted for abstinence time, the biological interdependence of semen parameters, and potential selection bias because of loss to follow-up.

RESULT(S)

Among couples using OI only or no treatment, 39% had a live birth, and relative to the highest quartile, the lowest quartiles of morphology (RD, -19 [95% CI, -23 to -15] per 100 couples), motility (RD, -13 [95% CI, -17 to -9]), concentration (RD, -22 [95% CI, -26 to -19]), and total motile count (RD, -18 [95% CI, -22 to -14]) were associated with fewer live births. For IUI, 26% had a live birth, and the lowest quartiles of volume (RD, -6 [95% CI, -11 to -0.4]), concentration (RD, -6 [95% CI, -11 to -0.1]), count (RD, -10 [95% CI, -15 to -4]), and total motile count (RD, -7 [95% CI, -13 to -1]) were associated with fewer live births. For IVF, 61% had a live birth, and only morphology (Q1 RD, -7 [95% CI, -14 to 0.2]; Q2 RD, -10 [95% CI, -17 to -2.2]) was associated with live birth.

CONCLUSION(S)

Semen parameters are critical in couples undergoing OI/IUI. Only low morphology was important for live birth after IVF. Although data supporting the use of semen parameters are fragmented across differing populations, current findings are generalizable across the range of male fertility and couple fertility treatments, providing evidence about which semen parameters are most relevant in which settings.

CLINICAL TRIAL REGISTRATION NUMBER

NCT#01857310.

TRPV1 channel in spermatozoa is a molecular target for ROS-mediated sperm dysfunction and differentially expressed in both natural and ART pregnancy failure

Bi-directional crosstalk between Ca2+ signaling and ROS modulates physiological processes as a part of a regulatory circuit including sperm function. The role of transient receptor potential vanilloid 1 (TRPV1) in this regard cannot be undermined. This is the first report demonstrating the Ca2+-sensitive TRPV1 channel to be under-expressed in spermatozoa of subfertile men, idiopathic infertile men, and normozoospermic infertile males with high ROS (idiopathic infertility and unilateral varicocele). To study the effect of TRPV1 in determining the fertility outcome, we compared the expression profile of TRPV1 in spermatozoa of male partners who achieved pregnancy by natural conception (NC+, n = 10), IVF (IVF+, n = 23), or ICSI (ICSI +, n = 9) and their respective counterparts with failed pregnancy NC (n = 7), IVF (n = 23), or ICSI (n = 10), by both immunocytochemistry and flow-cytometry. Reduced expression of TRPV1 in sperm of IVF ± and ICSI ± men with respect to that NC+ men imply its role in mediating successful fertilization. Unsuccessful pregnancy outcome with an underexpression of TRPV1 in sperm of NC-/IVF-/ICSI-men suggests its role in conception and maintenance of pregnancy. Since ROS is regarded as one of the major contributors to sperm dysfunction, the effect of H2O2 +/- TRPV1 modulators (RTX/iRTX) on acrosomal reaction and calcium influx was evaluated to confirm TRPV1 as a redox sensor in human sperm. A significant increment in the percentage of acrosome reacted spermatozoa along with augmented Ca2+-influx was observed after H2O2 treatment, both in the presence or absence of TRPV1 agonist resiniferatoxin (RTX). The effect was attenuated by the TRPV1 antagonist iodoresiniferatoxin (iRTX), indicating the involvement of TRPV1 in mediating H2O2 response. Enhancement of motility and triggering of acrosomal reaction post TRPV1 activation suggested that disruption of these signaling cascades in vivo, possibly due to down-regulation of TRPV1 in these subfertile males. Bioinformatic analysis of the crosstalk between TRPV1 with fertility candidate proteins (reported to influence IVF outcome) revealed cell death and survival, cellular compromise, and embryonic development to be the primary networks affected by anomalous TRPV1 expression. We therefore postulate that TRPV1 can act as a redox sensor, and its expression in spermatozoa may serve as a fertility marker.

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.

Influence of sperm DNA fragmentation on the clinical outcome of in vitro fertilization-embryo transfer (IVF-ET)

PURPOSE

To evaluate the effect of elevated sperm DNA fragmentation index (DFI) on fresh and frozen embryo transfer cycles.

METHODS

A retrospective study was performed with 549 fresh embryo transfer cycles and 1340 frozen embryo transfer cycles after in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) from 2016 to 2021.

RESULTS

The statistical results of 549 fresh embryo transfer cycles showed that the delivery rate in the normal sperm DFI group (43.9% vs. 27.1%, P = 0.014) was significantly higher than that in the abnormal sperm DFI group, and there were no significant differences in the biochemical pregnancy rate (59.0% vs. 50.8%, P = 0.232), clinical pregnancy rate (53.1% vs. 40.7%, P = 0.072), or miscarriage rate (17.3% vs. 33.3%, P = 0.098) between the two groups. The results of 1340 frozen embryo transfer cycles showed that the biochemical pregnancy rate (57.9% vs. 45.6%, P = 0.006) and clinical pregnancy rate (50.3% vs. 40.7%, P = 0.027) in the normal sperm DFI group were significantly higher than those in the abnormal sperm DFI group. The delivery rate (40.9% vs. 33.3%, P = 0.074) and miscarriage rate (18.6% vs. 18.0%, P = 0.919) were not significantly different between the two groups.

CONCLUSION

The increase of sperm DFI significantly reduced the delivery rate of fresh embryo transfer cycles and the biochemical pregnancy rate and clinical pregnancy rate of frozen embryo transfer cycles.

Exploration of the lactation function of protein phosphorylation sites in goat mammary tissues by phosphoproteome analysis

BACKGROUND

Protein phosphorylation plays an important role in lactation. Differentially modified phosphorylation sites and phosphorylated proteins between peak lactation (PL, 90 days postpartum) and late lactation (LL, 280 days postpartum) were investigated using an integrated approach, namely, liquid chromatography with tandem mass spectrometry (LC-MS/MS) and tandem mass tag (TMT) labeling, to determine the molecular changes in the mammary tissues during the different stages of goat lactation.

RESULTS

A total of 1,938 (1,111 upregulated, 827 downregulated) differentially modified phosphorylation sites of 1,172 proteins were identified (P values < 0.05 and fold change of phosphorylation ratios > 1.5). Multiple phosphorylation sites of FASN, ACACA, mTOR, PRKAA, IRS1, RPS6KB, EIF4EBP1, JUN, and TSC2 were different in PL compared with LL. In addition, the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the calcium signaling pathway, oxytocin signaling pathway and MAPK signaling pathway were enriched. The western blot results showed that the phosphorylation levels of ACACA (Ser80), EIF4EBP1 (Thr46) and IRS1 (Ser312) increased and JUN (Ser63) decreased in PL compared with LL. These results were consistent with the phosphoproteome results.

CONCLUSIONS

In this study, we identified for the first time the differentially modified phosphorylation sites in goat mammary tissues between PL and LL. These results indicate that the multiple differentially modified phosphorylation sites of FASN, ACACA, mTOR, PRKAA, IRS1, RPS6KB, EIF4EBP1, TSC2, and JUN and proteins involved in the calcium signaling pathway, oxytocin signaling pathway, and MAPK signaling pathway are worthy of further exploration.

Does a Very Short Length of Abstinence Improve Assisted Reproductive Technique Outcomes in Infertile Patients with Severe Oligo-Asthenozoospermia?

In recent years, a growing number of studies seem to support the beneficial effects of a very short abstinence period on sperm parameters, especially in patients with oligo-asthenozoospermia (OA). On this basis, the aim of this study was to evaluate the effects of a short period of abstinence (1 h) on intracytoplasmic sperm injection (ICSI) outcomes in infertile patients with severe OA. We performed a retrospective study on 313 ICSI cycles in which couples were divided into two different groups based on sperm parameters of the male partners. Group 1 included normozoospermic men or male partners with a mild OA (n = 223). Group 2 included male partners with severe OA (n = 90). They were asked to provide a second consecutive ejaculation after 1 h from the first one. The best ejaculate was used to perform ICSI. We found a significant increase of total (p < 0.001) and progressive motility (p < 0.001) in the second ejaculate of patients of Group 2 compared with those of the first one. Spermatozoa of the second ejaculate were chosen for ICSI for all patients in Group 2. We found statistically significant improvement of clinical pregnancy rate (p = 0.001) and embryo quality (p = 0.003) in couples in Group 2 compared to those of Group 1. No statistically significant difference was found in fertilization, implantation, live birth delivery, and miscarriage rates between the two groups. Therefore, a second semen sample collected after a very short time-interval in patients with severe OA allowed us to obtain significantly higher clinical pregnancy rate with improved embryo quality compared to normozoospermic men or patients with mild OA. Fertilization, implantation, live birth delivery, and miscarriage rates were similar between the two groups. The present study shows that a second consecutive ejaculate could represent a simple strategy to obtain better sperm parameters and assisted reproductive technology (ART) outcomes in infertile patients with mild-severe OA.

The Effect of Male Sexual Abstinence Periods on the Clinical Outcomes of Fresh Embryo Transfer Cycles Following Assisted Reproductive Technology: A Meta-Analysis

A sexual abstinence period (SAP) lasting for 2–7 days is recommended before undertaking semen analyses. However, there is no consensus regarding the length of the SAP for couples using assisted reproductive technology (ART). Therefore, a meta-analysis was performed to compare the effect of short SAPs (less than 4 days) and long SAPs (4–7 days) on the clinical outcomes of fresh embryo transfer cycles after ART. A total of four studies were included in the meta-analysis. Although the fertilization rate in short SAP couples was higher than that in long SAP couples, a pooled analysis demonstrated that it was not statistically significant (p = .09). The implantation rate was, however, significantly higher in short SAP couples (p = .0001). The pooled analysis revealed that the pregnancy rate was significantly higher in short SAP couples than that in long SAP couples. The overall odds ratio (OR) for the pregnancy rate was 1.44 (p = .0006). No significant difference in miscarriage rates between the short and long SAP couples was found (p = .88). The meta-analysis indicates that a shorter abstinence period could result in higher implantation and pregnancy rates for patients undertaking ART treatments.

The Effect of Ejaculatory Abstinence Interval on Sperm Parameters and Clinical Outcome of ART. A Systematic Review of the Literature

Since the publication of the first edition of the WHO (World Health Organization) Laboratory Manual for the examination of Human Semen in 1980, the reference values of sperm parameters have been updated on four occasions. Currently and globally, most of the laboratories analyzing semen samples use the latest, 5th edition of the manual that recommends ejaculatory abstinence from two to seven days before producing the sample for examination. While this standardized interval of time facilitates the interpretation of the results and research, no solid evidence exists to support the WHO-recommended abstinence time for a semen analysis in order to optimize clinical outcomes after assisted reproduction. Most of the studies refer to different clinical outcomes, different groups of patients and different editions of the WHO Laboratory Manual, including heterogeneous intervals of abstinence or sperm parameters. The aim of the current systematic review was to evaluate available evidence correlating ejaculatory abstinence time with clinical outcomes and sperm parameters analyzed according to the last edition of the World Health Organization Laboratory Manual reference values in different male populations. The results from the included studies indicate that WHO abstinence recommendations may need revision, given that a shorter ejaculatory abstinence interval appears to be associated with improved sperm parameters, such as sperm DNA fragmentation, progressive motility or morphology, while evidence suggests a potential increase in embryo euploidy rates and pregnancy outcomes.

Spatio-temporal landscape of mouse epididymal cells and specific mitochondria-rich segments defined by large-scale single-cell RNA-seq

Spermatozoa acquire their fertilizing ability and forward motility during epididymal transit, suggesting the importance of the epididymis. Although the cell atlas of the epididymis was reported recently, the heterogeneity of the cells and the gene expression profile in the epididymal tube are still largely unknown. Considering single-cell RNA sequencing results, we thoroughly studied the cell composition, spatio-temporal differences in differentially expressed genes (DEGs) in epididymal segments and mitochondria throughout the epididymis with sufficient cell numbers. In total, 40,623 cells were detected and further clustered into 8 identified cell populations. Focused analyses revealed the subpopulations of principal cells, basal cells, clear/narrow cells, and halo/T cells. Notably, two subtypes of principal cells, the Prc7 and Prc8 subpopulations were enriched as stereocilia-like cells according to GO analysis. Further analysis demonstrated the spatially specific pattern of the DEGs in each cell cluster. Unexpectedly, the abundance of mitochondria and mitochondrial transcription (MT) was found to be higher in the corpus and cauda epididymis than in the caput epididymis by scRNA-seq, immunostaining, and qPCR validation. In addition, the spatio-temporal profile of the DEGs from the P42 and P56 epididymis, including transiting spermatozoa, was depicted. Overall, our study presented the single-cell transcriptome atlas of the mouse epididymis and revealed the novel distribution pattern of mitochondria and key genes that may be linked to sperm functionalities in the first wave and subsequent wave of sperm, providing a roadmap to be emulated in efforts to achieve sperm maturation regulation in the epididymis.

Two subsequent seminal productions: A good strategy to treat very severe oligoasthenoteratozoospermic infertile couples

BACKGROUND

Sexual abstinence is considered one of the several factors that influence sperm quality. Recent studies show that a shortening of the abstinence period could be beneficial mostly in oligoasthenoteratozoospermic (OAT) patients.

OBJECTIVE

Retrospective study to verify the efficacy of a second semen sample after a short abstinence to treat severe OAT infertile patients.

MATERIALS AND METHODS

127 couples treated between May 2014 and May 2018 were divided into two groups. Study Group 1 (75 cycles): severe OAT characteristics: count <0.2 × 10⁶ /mL no progressive motility; count ≥0.2 × 10⁶ /mL and no total or progressive motility; 0% normal morphology; a second semen sample was requested after abstinence of 2 h. Control Group 0 (52 cycles): normozoospermic or mild OAT; only one sample was requested. Intracytoplasmic sperm injection was utilized in all cases.

RESULTS

All semen parameters were significantly different between Group 0 vs both samples of Group 1 (p < 0.001), excluding volume between Group 0 and 1st sample of Group 1 (p = 0.682). The comparison between 1st and 2nd samples from Group 1 showed significant differences in volume, total and progressive motility and morphology (p < 0.001, p < 0.001, p < 0.020) but not in total sperm count (p = 0.970). Fertilization, pregnancy rate/transfer, implantation and miscarriage rates were 85.9% and 61.1% (p < 0.001), 30.6% and 35.8% (p = 0.700), 17.5% and 24.0 (p = 0.292), 20.0% and 25.0% (p = 0.017) in Group 0 and Group 1 respectively.

DISCUSSION AND CONCLUSION

The results show that a short abstinence in severe OAT patients allows us to obtain spermatozoa with better motility. The request for a second semen sample in couples with extreme semen parameters is a valid and simple strategy that helps to achieve the same probability of pregnancy compared to a Control Group. Furthermore, it allows us to utilize fresh spermatozoa avoiding the need to resort to cryopreserved reserves or testicular surgery.

Current Insights and Latest Updates in Sperm Motility and Associated Applications in Assisted Reproduction

Spermatozoon is a motile cell with a special ability to travel through the woman’s reproductive tract and fertilize an oocyte. To reach and penetrate the oocyte, spermatozoa should possess progressive motility. Therefore, motility is an important parameter during both natural and assisted conception. The global trend of progressive reduction in the number and motility of healthy spermatozoa in the ejaculate is associated with increased risk of infertility. Therefore, developing approaches for maintaining or enhancing human sperm motility has been an important area of investigation. In this review we discuss the physiology of sperm, molecular pathways regulating sperm motility, risk factors affecting sperm motility, and the role of sperm motility in fertility outcomes. In addition, we discuss various pharmacological agents and biomolecules that can enhance sperm motility in vitro and in vivo conditions to improve assisted reproductive technology (ART) outcomes. This article opens dialogs to help toxicologists, clinicians, andrologists, and embryologists in understanding the mechanism of factors influencing sperm motility and various management strategies to improve treatment outcomes.

One day is better than four days of ejaculatory abstinence for sperm function

According to the World Health Organization guidelines, ejaculatory abstinence (EA) of 2–7 days is recommended for semen analysis. This study aimed to determine how seminal quality may be affected by two EA periods from the same man. Seminal samples from 65 men were evaluated by conventional semen analysis and qualitative characteristics after 1 and 4 days of EA (two samples/man). The semen was qualitatively analyzed by examining oxidative activity (intracellular and seminal plasma), sperm function (acrosome integrity, mitochondrial activity, and nuclear DNA integrity), and epididymal function. As expected, samples collected after 1 day of EA showed a decrease in volume and sperm total number compared to samples collected after 4 days of EA. The sperm motility of the samples collected after 1 day of EA was better compared to samples collected after 4 days of EA. Oxidative activity measured was lower after 1 day of EA compared with those measured after 4 days of EA. With regards to sperm function, samples collected after 1 day of EA showed an increase in acrosome integrity, mitochondrial activity, and nuclear DNA integrity compared with samples collected after 4 days of EA. Epididymal function showed no difference between the two-time points. Although samples collected after 4 days of EA showed better results for sperm quantity, samples collected after 1 day of EA showed better qualitative results, including motility, oxidative activity, and sperm function. Thus, it can be concluded that sperm storage at the epididymal tail may make spermatozoa more susceptible to oxidative damage.

Social Media Sensationalism in the Male Infertility Space: A Mixed Methodology Analysis

Purpose

Infertile couples increasingly turn to the internet for medical guidance. The aims of this study were: (1) to identify popular male infertility content on social media, and (2) to assess the accuracy and quality of this content. We hypothesized that inaccurate/misleading information proliferates online.

Materials and Methods

We used the analytics module BuzzSumo to identify article links that were most shared on Facebook, Pinterest, Reddit, and Twitter related to male infertility during September 2018 to August 2019. We excluded articles with <100 engagements, defined as “likes,” “comments,” and “shares.” Two researchers graded content as accurate, misleading, or inaccurate by comparing content to references cited and contemporary research. Inter-rater reliability was determined with Cohen's κ. Binary logistic regression was performed to compare user engagement with accurate versus inaccurate/misleading articles.

Results

Fifty-two unique article links were identified, with 421,004 total engagements. Thirty-four articles referenced 15 scientific studies; no reference was available for 18 links. Fifty-six percent of articles were accurate and 44% misleading/inaccurate (κ=0.743). No significant difference was found in total engagement between accurate vs. misleading/inaccurate links (p=0.805). Twenty-four percent of engagements referenced studies using non-human models, and 26% of studies had sample sizes <100.

Conclusions

Social media platforms foster engagement with male infertility information. However, sensationalism predominates, as patients are highly likely to encounter misleading/inaccurate information, articles that overstate implications of animal research, and conclusions made based on limited sample sizes. Urologists should consider adding social media to their armamentarium to stave off misinformation and engage proactively with patients.

Sperm Parameters before and after Swim-Up of a Second Ejaculate after a Short Period of Abstinence

Background: Recent studies have supported the beneficial effects of a short abstinence period on sperm parameters. The aim of this study was to assess sperm motility, morphology and DNA fragmentation before and after swim-up of a second ejaculate obtained after a short abstinence period in normozoospermic men and oligo-astheno-teratozoospermic (OAT) patients. Material and methods: Semen analyses and swim-up preparations of two consecutive semen samples (collected within 1 h) were carried out in 30 normozoospermic and 35 OAT patients enrolled in an assisted reproductive technique (ART) program. Results: Compared to the first ejaculate, the second sample showed a higher percentage of spermatozoa with normal form (p < 0.01) and lower percentage of spermatozoa with DNA fragmentation (p < 0.01) in normozoospermic men, whereas a higher percentage of spermatozoa with progressive motility (p < 0.001) and normal morphology (p < 0.0001) was found in OAT patients. Swim-up separation showed a lower DNA fragmentation rate (p < 0.05) in the second ejaculate in normozoospermic men, whereas the second ejaculate of OAT patents showed an increase in normally-shaped spermatozoa (p < 0.01) and lower percentage of spermatozoa with fragmented DNA (p < 0.001) compared to the first one. Conclusions: Swim-up separation of a second ejaculate collected within 1 h might be suggested for ART procedures, especially in OAT patients.

Human sperm acrosomal status, acrosomal responsiveness, and acrosin are predictive of the outcomes of in vitro fertilization: A prospective cohort study

The sperm acrosome reaction (AR) is a physiological secretory course of membrane fusion and hydrolytic enzymes, as well as matrix protein release, enabling spermatozoa to penetrate the egg surroundings. An instable acrosomal status before a specific stimulus, insufficient acrosomal responsiveness, or inadequate enzymatic activity of acrosomal content can be detrimental to male fertility. This prospective cohort study was designed to determine whether three human sperm acrosome evaluation parameters-including spontaneous AR rate, AR after calcium ionophore A23187 challenge (ARIC) rate, and modified Kennedy acrosin activity-can predict fertilization outcomes in vitro and are correlated with male characteristics. A total of 485 eligible couples undergoing in vitro fertilization (IVF) therapy were included in two phases of this study. In a 'construction phase', three acrosome evaluation parameters were determined simultaneously in 132 cases, whereas in a 'validation phase', the spontaneous AR rate was determined in 353 cases. The results of the 'construction phase' revealed that the spontaneous AR rate was the only significant predictor of fertilization outcome (unadjusted odds ratio [OR] = 0.68, 95% confidence interval [CI]: 0.53-0.88, P =  0.003; adjusted OR = 0.64, 95% CI: 0.43-0.95, P =  0.03), and the cut-off value for total fertilization failure (TFF) prediction, determined by ROC curve analysis, was 9.91%; higher acrosin activity was shown to predict a higher fertilization rate only when patients were divided into groups (≥25 μIU/10⁶ spermatozoa, 14-25 μIU/10⁶ spermatozoa, <14 μIU/10⁶ spermatozoa). The spontaneous AR rate was negatively correlated with sperm motility, forward progression motility, and normal morphology; modified Kennedy acrosin activity was positively correlated with normal morphology; and the ARIC rate was not correlated with any of the male characteristics. A similar result was obtained for the spontaneous AR rate in the 'validation phase', and the cut-off value in predicting TFF was calibrated for 9.52%. Clinically, patients can voluntarily choose spontaneous AR rate alone or in combination with modified Kennedy acrosin activity to predict TFF, and early rescue intracytoplasmic sperm injection (ICSI), half ICSI, or full ICSI should be considered in advance for men with spontaneous AR rates ≥9.52% or spontaneous AR rates ≥9.52% and AE activities <25 μIU/10⁶ spermatozoa.