Impact of sperm DNA fragmentation in couples with unexplained recurrent pregnancy loss: A cross-sectional study.

OBJECTIVE: Recurrent pregnancy loss (RPL) has a multifactorial etiology, with a majority of cases remaining unexplained. To account for these unexplained cases, possible male factors are being explored. Conventional semen analysis lacks a qualitative assessment of sperms and information regarding sperm DNA integrity. Sperm DNA fragmentation (SDF) has diagnostic value in unexplained RPL, and it may account for a number of unexplained cases. Hence, we planned a study to explore and evaluate the impact of sperm DNA fragmentation in couples with unexplained recurrent pregnancy losses. STUDY DESIGN: Analytical cross-sectional study was conducted at a tertiary-level referral facility in India between August 2021 and July 2023. Participants (n = 70) were divided into two groups-male partners of couples with unexplained RPL (following spontaneous conceptions) (n = 35) and men with at least one previous live birth (spontaneous or following fertility treatments for female factor infertility such as ovulation induction or intrauterine insemination) as controls (n = 35). Neither of the two groups of couples recruited for this study had undergone ART as fertility treatment. Primary outcome assessed was mean DNA fragmentation index (DFI). Secondary outcomes included differences in semen parameters such as sperm concentration, progressive sperm motility and morphology, proportion of men with high (≥30%) and low DFI in the two groups, and the association between various semen parameters and DFI. RESULTS: Univariate logistic regression revealed that sperm DNA fragmentation was higher in men with unexplained RPL (30.0; IQR (interquartile range) 19.0, 46.0) as compared to controls (22.0; IQR 14.0, 30.0) although it was not statistically significant (OR, odds ratio, 1.02; 95% CI 1.0-1.1, p = 0.08). A higher proportion of men with unexplained RPL had DFI ≥30% compared to controls (54.2% vs. 25.7%; OR 3.43 (95% CI 1.2-9.4); p = 0.02). No statistically significant differences were observed in semen volume, sperm concentration, progressive motility, and morphology between the two groups. Sperm DNA fragmentation index also showed a weak but significant inverse relationship with sperm morphology (r = -0.336, p = 0.004). CONCLUSION: The current study did not show any significant difference in the mean sperm DNA fragmentation levels in male partners of couples with unexplained RPL compared to controls. However, a higher proportion of men with DFI ≥30% were observed in unexplained RPL population when compared to controls.

Correlation of Sperm DNA Fragmentation Index With Semen Parameters, Lifestyle and Clinical Pregnancy Outcome After Intracytoplasmic Injection.

Objective: This study aimed to measure the correlation of sperm DNA fragmentation with semen parameters, lifestyle, and fertility outcomes after intracytoplasmic injection (ICSI). Materials and methods: The partners who were candidates for ICSI with a history of one In vitro fertilization (IVF) failure or male factor were recruited in the study. Semen parameters including sperm count, motility, and morphology as well as DNA fragmentation index (DFI) (that were divided into 2 groups as high (>15%), and low (≤15%) fragmentation scales) were evaluated either. The correlation of DFI with semen parameters, lifestyle, and clinical pregnancy after ICSI were compared between groups. Results: In 120 included couples, 59 men (49.2%) had DFIs ≤ 15% and 61 (50.8%) cases had DFIs >15%. In the group with higher DFI, abnormal morphology (p=0.010) was higher whereas, progressive motility (p=0.001), total motility (p<0.001), and total count (p<0.001) of sperm were significantly lower. In addition, the DFI was significantly higher in the subgroup of male infertility (0.012). Logistic regression showed that a lower risk of DFI>15% was associated with higher values of progressive motility (OR=0.97, p=0.001), total motility (OR=0.96, p=<0.001), count (OR=0.96, p=<0.001) and even clinical pregnancy (OR=0.27, p=0.011). However, a history of testicular surgery was associated with a higher risk of DFI>15% (OR=3.37, p=0.046). Although no correlation was found between male age and lifestyle components with DFI, the number of embryos was lower in DFI≥15% (p<0.001). Conclusion: DFI provide a clinically important measurement of sperm quality and have an impact on IVF outcomes; however, lifestyle components may not correlate with DFI.

What sperm parameters effect blastocyst formation and quality during ICSI with severe male infertility.

Sperm-derived genetic material contributes half of the genome to the embryo, hence it's crucial to investigate which sperm parameter influences blastocyst formation in the intracytoplasmic sperm injection (ICSI) cycles with severe male infertility. The retrospective study analyzed 296 ICSI cycles with severe oligoasthenoteratozoospermia (OAT) and 99 ICSI cycles with preimplantation genetic testing for aneuploidy (PGT-A). Following the correlation analysis, data stratifications were performed in the OAT ICSI subgroup. The results showed that the matching blastocyst in the OAT ICSI cycles had inferior sperm parameters. DFI and sperm morphology had an influence on the blastocyst formation rate and the high-quality blastocysts formation rate on Day6, but no significant effect on the blastocyst development on Day 5. The high-quality blastocysts formation rate and ratio of high-quality blastocyst on Day 6 were demonstrably better in the subgroup of the teratozoospermic morphology when DFI was within the normal range. In the case of the normal sperm morphology, no statistically significant difference was found in blastocyst development, although there were numerical differences within different DFI subgroups. It was concluded that the blastocyst quality and development declined with the decreased sperm qualities.

Shugan Tongluo Qiangjing recipe protects against varicocele of EVC rats through modulating sperm DNA damage, telomere expression and oxidative stress.

Varicocele (VC) refers to expansion and tortuosity of spreading venous plexus in spermatic cord due to poor blood flow. This study aimed to investigate effects of Shugan Tongluo Qiangjing recipe (SGTL) on sperm DNA damage and oxidative stress in experimental VC (EVC) rats. EVC model was established by partial ligation of left renal vein. Spermatic vein diameter, testicular weight, sperm DNA fragmentation index (DFI) were evaluated. Telomere reverse transcriptase (TERT) expression, telomere gene transcription, and testicular tissue morphology were determined·H2O2, catalase, SOD, T-AOC were measured with colorimetry. SGTL significantly decreased spermatic vein diameter (P=0.000) and increased testicular weight (P=0.013) of rats compared those of EVC rats. SGTL maintained testicular tissue morphology in EVC rats. SGTL markedly reduced sperm DFI value in sperm of rats compared to EVC rats (P=0.000). SGTL significantly enhanced TERT expression and telomere gene transcription (P=0.028) in testis of rats compared to EVC rats. SGTL reduced H2O2 levels (P=0.001) and promoted CAT activity (P=0.016), SOD activity (P=0.049), and T-AOC activity (P=0.047) of rats, compared to EVC rats. In conclusion, SGTL could reduce pathogenic process of EVC by reducing sperm DNA damage and regulating telomere length in EVC rats, which may be related to oxidative stress regulation.

Quantifying the association of sperm DNA fragmentation with assisted reproductive technology outcomes: An umbrella review.

BACKGROUND: Systematic reviews and meta-analyses are instrumental in shaping clinical practice. However, their findings can sometimes be marred by discrepancies and potential biases, thereby diluting the strength of the evidence presented. Umbrella reviews serve to comprehensively assess and synthesise these reviews, offering a clearer insight into the quality of the evidence presented. In the context of the relationship between sperm DNA fragmentation (SDF) and assisted conception outcomes, there is a divergence in the literature. Some reviews suggest a clear cause-and-effect linkage, whereas others present conflicting or inconclusive results. OBJECTIVES: In this umbrella review we aimed to synthesise the evidence collated in systematic reviews and meta-analyses summarising the association of SDF with assisted reproductive technology (ART) outcomes. SEARCH STRATEGY: After preregistration (https://doi.org/10.17605/OSF.IO/6JHDP), we performed a comprehensive search of the PubMed, Scopus, Cochrane Library, Web of Science and Embase databases. We conducted a search for systematic reviews on the association between SDF and ART without any restrictions on language or publication date. SELECTION CRITERIA: Systematic reviews and meta-analyses assessing the association between SDF and ART outcomes were eligible. DATA COLLECTION AND ANALYSIS: We assessed the quality of the included reviews using AMSTAR 2 and ROBIS, and determined the degree of overlap of primary studies between reviews estimating the corrected covered area (CCA), adjusted for structural missingness. We evaluated the most recent reviews assessing the association of SDF with live birth, pregnancy, miscarriage, implantation, blastulation and fertilisation. The synthesis of evidence was harmonised across all included quantitative syntheses, re-estimating the odds ratio (eOR) in random-effects meta-analyses with 95% confidence intervals (95% CIs) and 95% prediction intervals (95% PIs). We categorised the evidence strength into convincing, highly suggestive, suggestive, weak or nonsignificant, according to the meta-analysis re-estimated P-value, total sample size, I2 statistic for heterogeneity, small study effect, excess significance bias and the largest study significance. MAIN RESULTS: We initially captured and screened 49 332 records. After excluding duplicate and ineligible articles, 22 systematic reviews, 15 of which were meta-analyses, were selected. The 22 reviews showed a moderate degree of overlap (adjusted CCA 9.2%) in their included studies (overall n = 428, with 180 unique studies). The 15 meta-analyses exhibited a high degree of overlap (adjusted CCA = 13.6%) in their included studies (overall n = 274, with 118 unique studies). AMSTAR 2 categorised the quality of evidence in 18 reviews as critically low and the quality of evidence in four reviews as low. ROBIS categorised all the reviews as having a high risk of bias. The re-estimated results showed that the association of SDF with live birth was weak in one and nonsignificant in four meta-analyses. Similarly, the association of SDF with pregnancy, miscarriage, implantation, blastulation and fertilisation was also weak or nonsignificant. The association of high SDF with different ART outcomes was also weak or nonsignificant for different interventions (IVF, ICSI and IUI) and tests. CONCLUSIONS: This umbrella review did not find convincing or suggestive evidence linking SDF with ART outcomes. Caution should be exercised in making any claims, policies or recommendations concerning SDF.

Relationship of environmental exposure temperature and temperature extremes on sperm DNA fragmentation index in men with different BMI values and the indirect effect of DNA fragmentation index on semen parameters.

Prior studies have established a significant correlation between the DNA fragmentation index (DFI) and infertility. Additionally, certain investigations suggest that environmental exposure may serve as an etiological factor impacting semen quality. This study aimed to explore the impact of season, ambient temperature, and weather extremes on the DFI of sperm, along with other relevant parameters. Furthermore, it sought to assess how ambient temperature affects the DFI of sperm and other semen parameters in populations with varying BMI values. Additionally, the study analyzed the transient indirect effect of DFI on sperm parameters. This retrospective study analyzed semen samples from 11,877 men, selected based on female factor considerations, spanning from January 2016 to December 2021. Participants were grouped according to the season of semen collection. The results showed that samples collected in summer had a lower semen volume and sperm motility, while those collected in autumn had a lower DFI. We analyzed the exposure-response ratio between environmental exposure temperature and semen parameters using a generalized additive model. Results showed that the curve of the exposure-response relationship was U-shaped or inverted U-shaped; when the air temperature exposure was below the threshold, for each degree of temperature increase, the total sperm motility, sperm concentration, and progressive motility increased by 0.16 %, 0.29 × 10 (Levine, 1999)/ml and 0.14 %, respectively, while the DFI and inactivity rate decreased by 0.078 % and 0.15 %, respectively. When the air temperature exposure exceeded the threshold, for each degree of temperature increase, the sperm concentration, total sperm motility, semen volume and progressive motility decreased by 0.42 × 10 (Levine, 1999)/ml, 0.11 %, 0.0078 ml and 0.15 %, respectively, while the DFI and inactivity rate increased by 0.13 % and 0.12 %, respectively. Extremely cold weather during spermatogenesis was positively correlated with DFI, and extremely hot weather was negatively correlated with sperm motility. Subgroup analysis revealed that individuals classified as overweight / obese exhibited more pronounced changes in sperm parameters and the DFI in response to variations in environmental exposure temperature compared to those with a normal BMI. In the analysis of the relationship between DFI and sperm parameters, the results showed an inverted U-shape relationship between DFI and semen volume, and a negative correlation between DFI and sperm concentration and sperm motility. And we found that ambient temperature affects sperm parameters through DFI at low as well as average temperatures, whereas at high temperatures this indirect effect is no longer present.

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.

The impact of female BMI on sperm DNA damage repair ability of oocytes and early embryonic development potential in intracytoplasmic sperm injection cycles.

Background: Obesity adversely influences the quality of oocytes and embryos and can affect DNA repair in embryos, leading to reproductive issues. However, the effects of body mass index (BMI) on DNA repair ability in oocytes during intracytoplasmic sperm injection (ICSI) cycles have not yet been investigated. Therefore, this retrospective study aimed to analyze the influence of sperm DNA damage on embryo development and reproductive outcomes in overweight/obese and normal-weight women in ICSI cycles. Methods: A total of 1,141 patients who received the first fresh ICSI cycle treatments were recruited from July 2017 to July 2021. Based on the BMI of the women, all patients were divided into normal weight (18.5≤BMI<25 kg/m2; n=824; 72.22%) and overweight/obese (BMI≥25 kg/m2; n=317; 27.78%) groups. Furthermore, according to the sperm DNA fragmentation index (DFI), these two groups were subdivided into two subgroups: DFI<30% and DFI≥30%. Results: In the normal-weight women group, the embryonic development and reproductive outcomes of ICSI cycles were not statistically different between the two subgroups (DFI<30% and DFI≥30%). However, in the overweight/obese women group, couples with a sperm DFI≥30% had a significantly lower fertilization rate (76% vs. 72.7%; p=0.027), cleavage rate (98.7% vs. 97.2%; p=0.006), and high-quality embryo rate (67.8% vs. 62.6%; p=0.006) than couples with a sperm DFI<30%. Conclusion: When injected sperm with high DFI into the oocytes of overweight/obese women, resulting in lower fertilization, cleavage, and high-quality embryo rates in ICSI cycles, and the decreased early developmental potential of embryos from overweight/obese patients may be caused by the diminished capacity of oocytes to repair sperm DNA damage.

DNA strand displacement and TdT-Mediated DNA extension for swift, convenient, and quantitative evaluation of sperm DNA integrity and its clinical implications.

DNA integrity is crucial for the clinical pregnancy outcome and offspring health, while detection methods currently used (comet assay, TUNNEL assay, SCSA, etc.) can only provide the ratio of positive sperms at the cellular level and are unable to quantitatively detect the breakpoints at the DNA molecular level. Herein, we developed a detection system based on terminal deoxynucleotidyl transferase and DNA strand displacement fluorescent probe, which could efficiently and conveniently measure the number of 3'-OH (equivalent to the number of breakpoints). We further investigated the use of this technique in assisted reproduction after completing the principle verification, system optimization, and research on analytical performance. The detection system was shown to have a good linear range from 0.01 nM to 4 nM, using single-stranded DNA with 3'-OH end as the calibrator. The system underwent thorough optimization for stability and accuracy. In comparison to the widely accepted index DFI detected by SCSA, the new system demonstrated reasonable correlation and better prediction efficiency. Its applicability was also proven through its use in assisted reproductive technology procedures.

Quality of testicular spermatozoa improves with changes in composition of culture medium.

BACKGROUND: Spermatozoa retrieved from the testis and epididymis are deprived of the beneficial effects of seminal fluid. Thus applying an artificial medium with normal seminal fluid characteristics, known as artificial seminal fluid (ASF), may provide an appropriate condition for improving some sperm parameters in azoospermia. The objective was to investigate the impact of in vitro exposure of testicular and epididymal spermatozoa to ASF on sperm quality. The study was conducted on testicular (n = 20) and epididymal (n = 20) sperm specimens obtained from azoospermic men. Each sample was divided into two equal parts: Part I) for processing and incubation with Ham's F10 medium; Part II) for processing and incubation with ASF. RESULTS: After 2 h incubation, testicular sperm motility was significantly higher in ASF than in Ham's F10 medium. In comparison to 0 h, mitochondrial membrane potential levels of testicular spermatozoa were significantly higher after 2 h and 24 h in ASF and after 24 h in Ham's F10 medium. Furthermore, the data indicated significantly lower rates of epididymal spermatozoa with high MMP in both media after 24 h. There were no significant differences in the DNA fragmentation index of testicular and epididymal spermatozoa between ASF and Ham's F10 medium at different time points. CONCLUSION: The results demonstrated that in vitro incubation of testicular spermatozoa improved their motility more effectively than Ham's F10 medium in the short term (2 h), but had no effect on epididymal spermatozoa. Since the physiology of testicular spermatozoa is different from that of ejaculated spermatozoa, it seems that a special environment should be designed and used for each of them.

RéSUMé: CONTEXTE: Les spermatozoïdes prélevés dans les testicules et les épididymes sont privés des effets bénéfiques du liquide séminal. Ainsi, l'utilisation d'un milieu artificiel avec des caractéristiques normales du liquide séminal, connu sous le nom de liquide séminal artificiel (ASF), peut constituer une condition appropriée pour améliorer certains paramètres des spermatozoïdes obtenus dans l'azoospermie. L'objectif était d'étudier l'impact de l'exposition in vitro de spermatozoïdes testiculaires et épididymaires à l'ASF sur la qualité du sperme. L'étude a été menée sur des échantillons de spermatozoïdes testiculaires (n = 20) et épididymaires (n = 20) obtenus chez des hommes azoospermiques. Chaque échantillon a été divisé en deux parties égales: Partie I) pour le traitement et l'incubation avec le milieu F10 de Ham; Partie II) pour la transformation et l'incubation avec l'ASF. RéSULTATS: Après 2 h d'incubation, la mobilité des spermatozoïdes testiculaires était significativement plus élevée dans l'ASF que dans le milieu F10 de Ham. Par rapport à 0 h, les niveaux du potentiel de membrane mitochondriale (PMM) des spermatozoïdes testiculaires étaient significativement plus élevés après 2 h et 24 h dans l'ASF, et après 24 h dans le milieu F10 de Ham. En outre, les données ont indiqué des taux significativement plus faibles de spermatozoïdes épididymaires avec un PMM élevé dans les deux milieux après 24 heures. Il n'y avait pas de différences significatives dans l'indice de fragmentation de l'ADN des spermatozoïdes testiculaires et épididymaires entre l'ASF et le milieu F10 de Ham aux différents temps. CONCLUSION: Les résultats ont montré que l'incubation in vitro de spermatozoïdes testiculaires dans l'ASF améliorait leur mobilité plus efficacement que le milieu F10 de Ham à court terme (2 h), mais n'avait aucun effet sur les spermatozoïdes épididymaires. Étant donné que la physiologie des spermatozoïdes testiculaires est différente de celle des spermatozoïdes éjaculés, il semble qu'un environnement spécial devrait être conçu et utilisé pour chacun d'eux.

The effect of sperm DNA fragmentation on in vitro fertilization outcomes of unexplained infertility.

BACKGROUND: Infertility is caused by heterogeneous risks, but most of them are unexplained. The sperm DNA Fragmentation Index (DFI) was increasingly acknowledged as a parameter for the evaluation of male infertility. This study aimed to investigate the association between sperm DFI and laboratory and clinical outcomes in a population with unexplained infertility. METHODS: The clinical data of an infertile population was collected for the selection of reproductive patients with unexplained infertility. The authors classified the patients with normal sperm parameters in a control group (DFI < 25%) and an observation group (DFI ≥ 25%) and compared the difference in basal characteristics, laboratory, and clinical outcomes between the two groups. The authors conducted a correlation analysis to examine the relationship between DFI and the number of D3 good-quality embryos, as well as the clinical pregnancy rate and live birth rate. A total of 176 cases were enrolled in the retrospective study. RESULTS: The observation group (n = 88) showed advanced male age, lower sperm concentration, progressive motility, and morphology assessment than the control group. In addition, lower No. of D3 good-quality embryos, clinical pregnancy rate, and the live birth rate were shown in the observation group. A negative correlation between the DFI and No. of D3 good-quality embryos (rs = -0.347, p < 0.001) or live birth rate (rs = -0.185, p = 0.028) was shown. CONCLUSIONS: Sperm DFI was a good indicator for the prediction of D3 good-quality embryos in unexplained infertility couples, but it did not provide sufficient information regarding clinical pregnancy outcome but live pregnancy outcome.

Deep Learning-Based Robust Automated System for Predicting Human Sperm DNA Fragmentation Index.

Background: Determining the DNA fragmentation index (DFI) by the sperm chromatin dispersion (SCD) test involves manual counting of stained sperms with halo and no halo. Aims: The aim of this study is to build a robust artificial intelligence-based solution to predict the DFI. Settings and Design: This is a retrospective experimental study conducted in a secondary in vitro fertilisation setup. Materials and Methods: We obtained 24,415 images from 30 patients after the SCD test using a phase-contrast microscope. We classified the dataset into two, binary (halo/no halo) and multiclass (big/medium/small halo/degraded (DEG)/dust). Our approach consists of a training and prediction phase. The 30 patients' images were divided into training (24) and prediction (6) sets. A pre-processing method M was developed to automatically segment the images to detect sperm-like regions and was annotated by three embryologists. Statistical Analysis Used: To interpret the findings, the precision-recall curve and F1 score were utilised. Results: Binary and multiclass datasets containing 8887 and 15,528 cropped sperm image regions showed an accuracy of 80.15% versus 75.25%. A precision-recall curve was determined and the binary and multiclass datasets obtained an F1 score of 0.81 versus 0.72. A confusion matrix was applied for predicted and actuals for the multiclass approach where small halo and medium halo confusion were found to be highest. Conclusion: Our proposed machine learning model can standardise and aid in arriving at accurate results without using expensive software. It provides accurate information about healthy and DEG sperms in a given sample, thereby attaining better clinical outcomes. The binary approach performed better with our model than the multiclass approach. However, the multiclass approach can highlight the distribution of fragmented and non-fragmented sperms.

SARS-CoV-2 infection reduces quality of sperm parameters: prospective one year follow-up study in 93 patients.

BACKGROUND: Short- and long-term implications of SARS-CoV-2 on the quality of the sperm and the results of this on fertility remain largely unknown due to lack of longitudinal studies. In this longitudinal observational cohort study, we aimed to analyse the differential effect and the impact of SARS-CoV-2 infection on different semen quality parameters. METHODS: Sperm quality was assessed using the World Health Organization criteria, DNA damage to sperm cells by quantifying the DNA fragmentation index (DFI) and the high-density stainability (HDS), IgA- and IgG-anti-sperm antibodies (ASA) were assessed with light microscopy. FINDINGS: SARS-CoV-2 infection was associated with sperm parameters that were independent of spermatogenic cycle like progressive motility, morphology, DFI and HDS, as well as spermatogenic cycle dependent parameters such as sperm concentration. Detection of IgA- and IgG-ASA allowed classification of patients in three different groups according to its sequence of appearance in sperm during post-COVID-19 follow-up. The maximum progressive motility was lowest during follow-up in patients without ASA (41.9%), intermediate in patients with only IgA-ASA (46.2%) and highest inpatients who had both IgA- and IgG-ASA (54.9%). INTERPRETATION: SARS-CoV-2 infection was associated with changes of all analysed sperm parameters to a different degree which is also observed in their return to normality and is suggestive of individual variations in the patient's immune system performance. Firstly, sperm production is decreased through temporal immune mediated arrest of active meiosis, and secondly immune induced sperm DNA damage prevents fertilization if transferred to the oocyte. Both mechanisms are temporal, and most sperm parameters return to baseline after infection. FUNDING: AML (R20-014), Femicare.

Association of embryo aneuploidy and sperm DNA damage in unexplained recurrent implantation failure patients under NGS-based PGT-A cycles.

PURPOSE: Recurrent implantation failure (RIF) is one of the most common conditions affecting In Vitro Fertilization (IVF)/Intracytoplasmic sperm injection (ICSI) outcomes. Aneuploidy embryos, one of the main types of embryos-related factors, was reported to be a major contributor to RIF. The present study aimed to examine the association between sperm DNA fragmentation index (DFI) and outcomes of next-generation sequencing (NGS)-based preimplantation genetic testing for aneuploidy (PGT-A) in unexplained RIF patients. METHODS: This study analyzed 119 couples with unexplained RIF who underwent 119 PGT-A cycles between January, 2017 and March, 2022. The 119 males were divided into 3 groups according to their sperm DFI levels: Group1 (low, DFI ≤ 15%, n = 50), Group2 (medium, 15% < DFI < 30%, n = 41) and Group3 (high, DFI ≥ 30%, n = 28). Sperm DFI was measured by sperm chromatin structure analysis (SCSA) technique. Trophectoderm biopsy on day 5 or 6 were performed with NGS technique. The following outcomes of PGT-A were analyzed and compared: fertilization, good-quality embryos, aneuploidy rate, miscarriage, live birth and newborn defects. RESULTS: The component of aneuploidy embryos was significantly higher in high DFI group (42.71%) than that of medium group (28.39%) and low group (27.80%). The miscarriage rate of high DFI group (27.27%) and medium group (14.29%) is significantly higher than that of low group (0.00%). No significant differences were found regarding fertility, good-quality embryo rate, pregnancy rate, live birth rate or newborn defects among three groups. CONCLUSION: The sperm DNA damage is associated with blastocyst aneuploidy and miscarriage rate in unexplained RIF cases. Embryo selection by PGT-A and efforts to decrease sperm DFI before IVF/ICSI treatments should be considered for those male patients with high DFI.

The influence and mechanistic action of sperm DNA fragmentation index on the outcomes of assisted reproduction technology.

We investigated the influence of DNA fragmentation index (DFI) on in vitro fertilization (IVF), embryo transfer (ET), and intracytoplasmic sperm injection (ICSI). We analyzed the semen parameters of 61 cycles in infertile couples undergoing IVF-ET and ICSI and determined DFI by sperm chromatin dispersion testing. Based on DFI, the patients were differentiated into a control group (DFI < 25%, n = 35) and a test group (DFI ≥ 25%, n = 26). Flow cytometry and immunofluorescence were used to investigate the extent of sperm reactive oxygen species (ROS) and apoptosis. We also investigated the effect of DFI on pregnancy outcomes of IVF-ET/ICSI. DFI was negatively related to sperm motility and positively correlated with ROS and apoptosis (P < 0.05). Abnormally elevated DFI reduced the rate of transplantable, high-quality embryos, implantation, clinical pregnancy, delivery, and live birth after IVF-ET, and increased the chance of early abortion per transfer cycle (P < 0.05). However, there was no significant correlation between DFI and fertilization rate, cleavage rate, transplantable rate, high-quality embryo rate, implantation rate, clinical pregnancy rate, early abortion rate, delivery rate and live birth rate when assisted by ICSI (P > 0.05). Sperm DNA integrity is crucial for fertilization and the development of healthy offspring. ROS may increase the level of DFI by inducing apoptosis in sperm.

Sperm DNA Fragmentation Index in Abortion or in Vitro Fertilization Failure in Presence of Normal Semen Analysis.

Role of male factor in recurrent abortion and in vitro fertilization failure has not been fully defined yet and there is much controversy about evaluating male patients with normal semen analysis. One of the factors that might help establish the male role is DNA fragmentation index. However, strong correlation between this factor and quality of semen, has caused many clinicians to believe that it does not help in abortion and implantation failure. We aim to assess this factor in our patients. In a prospective observational study, we assessed age, duration of infertility, undesired fertility related events (assisted reproductive techniques attempts and abortions), semen parameters and DNA fragmentation index in patients with multiple abortions or in vitro fertilization failures and analysed the results by statistical software SPSS version 24. DNA fragmentation index was remarkably correlated with age, duration of infertility and semen parameters. Among all groups in our study, patients with abnormal semen analysis had statistically significant higher level of DNA fragmentation. Ten percent of patients with normal or slightly abnormal semen analysis had abnormally high SDFI (sperm DNA fragmentation index). Checking DNA fragmentation index is recommended in all couples with fertilization problems even in the presence of normal semen analysis. It might be more reasonable to assess it in aged men, long duration of infertility or candidates with remarkable semen abnormality.

Assessment of cell-free DNA and apoptosis in an oocyte microenvironment: promising biomarkers to predict intracytoplasmic sperm injection outcomes.

Cell-free DNA (cf-DNA) is defined as DNA fragments that are released into the body fluids from apoptosis or necrosis cells, including follicular fluid (FF), which can affect the microenvironment of the oocyte associated with infertility. We aimed to investigate a relationship between apoptosis of cumulus cells (CCs) and cf-DNA levels in FF and clinical outcomes of women undergoing intracytoplasmic sperm injection (ICSI). Therefore, 82 FF samples were collected, and the corresponding CCs were isolated for ICSI procedures. FF cf-DNA concentration was quantified using ALU-quantitative polymerase chain reaction (PCR), and CCs DNA fragmentation index (DFI) was evaluated by the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labelling (TUNEL) method. We found that cf-DNA and DFI levels were significantly higher in FF and CCs samples related to the age of women ≥37 years compared with the age of women < 37 years. Moreover, in older and younger women, FF cf-DNA and CCs DFI levels were significantly lower when the anti-Müllerian hormone (AMH) level was > 1.1 ng/ml compared with when AMH ≤ 1.1 ng/ml. In addition, patients with a low number of retrieved oocytes ≤ 6 had significantly higher levels of CCs DFI and FF cf-DNA than women with a higher number of retrieved oocytes > 6. Additionally, we observed that higher levels of cf-DNA and DFI were associated with poor oocyte maturity and poor embryo quality. Finally, cf-DNA and DFI levels were significantly lower in pregnant women than in non-pregnant ones. We conclude that DFI and cf-DNA levels in the oocyte microenvironment could have potential use in evaluating oocyte and embryo developmental competence.

Advanced Paternal Age Affects the Sperm DNA Fragmentation Index and May Lead to Lower Good-quality Blastocysts.

Several studies show reductions in some seminal parameters in aged men and describe them as a consequence of many age-dependent changes in male organisms. This study aims to evaluate the impact of age on seminal parameters, particularly the DNA fragmentation index (DFI), and outcomes after in vitro fertilization (IVF) cycles. This is a retrospective study that includes 367 patients who underwent sperm chromatin structure assay testing between 2016 and 2021. The participants were split into three groups according to age: < 35 years (younger group, n = 63), 35-45 years (intermediate group, n = 227), and ≥ 45 years (older group, n = 77). The mean DFI (%) was compared. Among all patients, 255 received IVF cycles after DFI evaluation. For these patients, the sperm concentration, motility, and volume, as well as the fertilization rate, mean oocyte age, and good-quality blastocyst formation rate, were analyzed. One-way ANOVA was applied. The older group showed a significantly higher sperm than did the younger group (28.6% vs. 20.8% p = 0.0135). Despite not presenting a significant difference, the DFI level tends to be inversely related to good-quality blastocyst formation since the oocyte age was similar between the groups (32.0 v.s 33.6 vs. 32.3 years, respectively, p = 0.1183). Among aged men, the sperm DFI level is increased but other seminal parameters are not modified. Considering that men with a high sperm DFI can present some degree of infertility due to high sperm chromatin damage, male age should also be considered a limiting factor of IVF.

TLR-1, TLR-2, and TLR-6 MYD88-dependent signaling pathway: A potential factor in the interaction of high-DNA fragmentation human sperm with fallopian tube epithelial cells.

OBJECTIVE: The DNA integrity of spermatozoa that attach to fallopian tube (FT) cells is higher than spermatozoa that do not attach. FT epithelial cells can distinguish normal and abnormal sperm chromatin. This study investigated the effects of sperm with a high-DNA fragmentation index (DFI) from men with unexplained repeated implantation failure (RIF) on the Toll-like receptor (TLR) signaling pathway in human FT cells in vitro. METHODS: Ten men with a RIF history and high-DFI and 10 healthy donors with low-DFI comprised the high-DFI (>30%) and control (<30%) groups, respectively. After fresh semen preparation, sperm were co-cultured with a human FT epithelial cell line (OE-E6/E7) for 24 hours. RNA was extracted from the cell line and the human innate and adaptive immune responses were tested using an RT2 profiler polymerase chain reaction (PCR) array. RESULTS: The PCR array data showed significantly higher TLR-1, TLR-2, TLR-3, TLR-6, interleukin 1α (IL-1α), IL-1ß, IL-6, IL-12, interferon α (IFN-α), IFN-ß, tumor necrosis factor α (TNF-α), CXCL8, GM-CSF, G-CSF, CD14, ELK1, IRAK1, IRAK2, IRAK4, IRF1, IRF3, LY96, MAP2K3, MAP2K4, MAP3K7, MAP4K4, MAPK8, MAPK8IP3, MYD88, NFKB1, NFKB2, REL, TIRAP, and TRAF6 expression in the high-DFI group than in the control group. These factors are all involved in the TLR-MyD88 signaling pathway. CONCLUSION: The MyD88-dependent pathway through TLR-1, TLR-2, and TLR-6 activation may be one of the main inflammatory pathways activated by high-DFI sperm from men with RIF. Following activation of this pathway, epithelial cells produce inflammatory cytokines, resulting in neutrophil infiltration, activation, phagocytosis, neutrophil extracellular trap formation, and apoptosis.