Male Infertility Research Articles

Comparative Analysis of Fluorescence In Situ Hybridization and Next-Generation Sequencing in Sperm Evaluation: Implications for Preimplantation Genetic Testing and Male Infertility.

Pre-implantation genetic testing (PGT) is a crucial process for selecting embryos created through assisted reproductive technology (ART). Couples with chromosomal rearrangements, infertility, recurrent miscarriages, advanced maternal age, known single-gene disorders, a family history of genetic conditions, previously affected pregnancies, poor embryo quality, or congenital anomalies may be candidates for PGT. Preimplantation genetic testing for aneuploidies (PGT-A) enables the selection and transfer of euploid embryos, significantly enhancing implantation rates in assisted reproduction. Fluorescence in situ hybridization (FISH) is the preferred method for analyzing biopsied cells to identify these abnormalities. While FISH is a well-established method for identifying sperm aneuploidy, NGS offers a more comprehensive assessment of genetic material, potentially enhancing our understanding of male infertility. Chromosomal abnormalities, arising during meiosis, can lead to aneuploid sperm, which may hinder embryo implantation and increase miscarriage rates. This review provides a comparative analysis of fluorescence in situ hybridization (FISH) and next-generation sequencing (NGS) in sperm evaluations, focusing on their implications for preimplantation genetic testing. This analysis explores the strengths and limitations of FISH and NGS, aiming to elucidate their roles in improving ART outcomes and reducing the risk of genetic disorders in offspring. Ultimately, the findings will inform best practices in sperm evaluations and preimplantation genetic testing strategies.

A closer look: sperm analysis and clinical outcomes of microscopic and loupe-assisted varicocele repair in male infertility due to moderate-to-severe varicocele.

The aim of the study was to compare the clinical outcomes, sperm parameters, and complications of loupe-assisted and microscopic varicocele repair in patients with infertility due to moderate-to-severe varicocele. We included all male individuals over 18years of age who underwent inguinal varicocele repair at our center due to infertility. Subjects with azoospermia, genetic abnormalities such as Kallmann syndrome, incomplete medical records, or those lost to follow-up were excluded from the study. Patients were divided into two groups based on the magnification tool used (microscope or loupe). Follow-ups were conducted at 3months and 1year post-surgery. Sperm parameters, pregnancy rates, and surgical complications were recorded to compare the efficacy of the magnification tools. The Improvement Index for sperm parameters was calculated by dividing the difference between the post-operative and pre-operative parameters by the pre-operative parameter. An Improvement Index above 0.5 was considered a good outcome. Out of 104 patients, 58 underwent loupe-assisted and 46 underwent microscopic varicocele repair. Sperm concentration and progressive motility increased significantly in the semen analyses at three months and one year post-operation compared to pre-operative semen analyses. However, increases in sperm morphology were not statistically significant in either follow-up semen analysis. An Improvement Index greater than 0.5 (indicating a good outcome) was observed in 35.3%, 34.1%, and 15.2% of patients for sperm concentration, progressive motility, and morphology, respectively, after 3months, and 38.9%, 43.4%, and 22.4% after 1year. Nonetheless, there were no significant differences in the Improvement Index of sperm parameters between the two magnification methods. The operative duration was significantly longer with microscopic magnification (median of 70.0 [20.0] minutes vs. 45.0 [20.0] minutes) (p value < 0.001). Conversely, the pregnancy rates were 34.5% (20 patients) in the loupe-assisted group and 37.0% (17 patients) in the microscopic group, which was not significantly different (p value: 0.794). Similarly, the rate of complications was not significantly different, with 5 patients (10.9%) experiencing complications (4 hydroceles and 1 wound infection) in the microscopic group compared to 4 patients (6.9%) (3 hydroceles and 1 wound infection) in the loupe-assisted group (p value: 0.504). The current study's results indicate that the clinical outcomes, sperm parameters, and complications associated with loupe-assisted varicocele repair are comparable to those of microsurgical varicocele repair, which is considered the gold standard. We suggest conducting prospective studies to assess whether loupe-assisted varicocele repair is a safe alternative, especially in centers with limited or no access to surgical microscopes.

Effect of Oxidative Stress on Sperm TERRA Expression and Chromatin Function in Infertile Males: A Preliminary Finding

Telomeres are vital for cellular function. Oxidative stress is detrimental to telomere function as it causes telomere attrition. Increase in oxidative stress has a negative impact on sperm telomere and chromatin integrity and therefore, on sperm function and male fertility. TERRA, a long non-coding RNA is a fundamental component required for telomere length homeostasis. Aim: The present work aimed to study the effect of H2O2 induced oxidative stress on sperm TERRA expression and chromatin function. Methodology: 5 infertile and 5 fertile males were selected for the study. Baseline semen analysis was done as per WHO manual 2021. Sperm TERRA expression was assessed by real time qPCR. To assess chromatin function nuclear chromatin decondensation test was done. Results: Study showed that 500µM H2O2 increased TERRA expression as compared to untreated groups and the difference was found to be statistically significant. As compared to controls, cases showed more fold increase in TERRA expression. When treated samples of control and cases were compared, cases had more TERRA expression than controls however, the baseline TERRA expressions in untreated samples were less in cases as compared to controls. Both comparisons yielded statistically nonsignificant results. When nuclear chromatin decondensation was compared before and after H2O2 treatment, the percentage of sperm head decondensation decreased in both cases and controls. When treated and untreated samples of cases and controls were compared, the difference was statistically nonsignificant. Conclusion: Oxidative stress led to an increase in the expression of sperm TERRA and had a negative impact on nuclear chromatin decondensation. Similar studies with greater sample size can provide much more insight into TERRA mediated regulation of telomere function and chromatin integrity and how it is affected by oxidative stress.

Unilateral polyorchidism with severe male infertility: a case report

Polyorchidism is an uncommon congenital condition often discovered incidentally, which may significantly impact male fertility. We present a case of a 34-year-old man with unilateral polyorchidism and associated severe asthenozoospermia and teratozoospermia. Despite normal hormonal levels and no detected genetic anomalies, the patient’s sperm showed mitochondrial damage, and his fertility remained compromised after conservative management and assisted reproductive attempts. This case underscores the intricate relationship between polyorchidism and male infertility, highlighting the need for personalized management strategies and further research into its etiology and impact.

Normal male fertility in a mouse model of KPNA2 deficiency.

The nuclear transport of proteins is mediated by karyopherins and has been implicated to be crucial for germ cell and embryonic development. Deletion of distinct members of the karyopherin alpha family has been shown to cause male and female infertility in mice. Using a genetrap approach, we established mice deficient for KPNA2 (KPNA2 KO) and investigated the role of this protein in male germ cell development and fertility. Breeding of male KPNA2 KO mice leads to healthy offsprings in all cases albeit the absence of KPNA2 resulted in a reduction in sperm number by 60%. Analyses of the KPNA2 expression in wild-type mice revealed a strong KPNA2 presence in meiotic germ cells of all stages while a rapid decline is found in round spermatids. The high KPNA2 expression throughout all meiotic stages of sperm development suggests a possible function of KPNA2 during this phase, hence in its absence the spermatogenesis is not completely blocked. In KPNA2 KO mice, a higher portion of sperms presented with morphological abnormalities in the head and neck region, but a severe spermiogenesis defect was not found. Thus, we conclude that the function of KPNA2 in round spermatids is dispensable, as our mice do not show any signs of infertility. Our data provide evidence that KPNA2 is not crucial for male germ cell development and fertility.

Identification and Manipulation of Spermatogonial Stem Cells with the Aim of Inducing Spermatogenesis in Vitro.

Assisted reproduction techniques for infertile men with non-obstructive azoospermia require a sufficient number of functional germ cells produced in vitro. Understanding the mechanisms that allow the resumption of spermatogenesis outside the testicular environment is crucial for fertility preservation in these patients. A review of the literature was conducted using databases such as PubMed, Scopus and Web of Science, with keywords including "spermatogonial stem cell," "germ cells," "male factor infertility," and "enrichment and propagation of SSCs in vitro." Currently, two models-"in vivo" and "in vitro"-have been developed for producing haploid germ cells. The "in vivo" models include spermatogonial stem cell transplantation and testicular xenograft techniques. In contrast, the "in vitro" models consist of conventional culture systems, organ culture, and three-dimensional culture systems, all designed to induce spermatogenesis in vitro. These culture systems enable the simulation of the seminiferous epithelium in vitro, which facilitates better regulation of cell-signaling pathways that control the self-renewal and differentiation of SSCs. This review provides up-to-date information on the organization of SSCs, focusing on the identification, proliferation, and differentiation of spermatogonia in vitro.

Study on the influence of the sY1192 gene locus in the AZFb/c region on sperm quality and pregnancy outcome.

Y chromosome microdeletions are an important cause of male infertility. At present, research on the Y chromosome is mainly focused on analyzing the loss of large segments of the azoospermia factor a/b/c (AZFa/b/c) gene, and few studies have reported the impact of unit point deletion in the AZF band on fertility. This study analyzed the effect of sperm quality after sY1192 loss in 116 patients. The sY1192-independent deletion accounted for 41.4% (48/116). Eight patterns were found in the deletions associated with sY1192. The rate of sperm detection was similar in the semen of patients with the independent sY1192 deletion and the combined sY1192 deletions (52.1% vs 50.0%). The patients with only sY1192 gene loss had a higher probability of sperm detection than the patients whose sY1192 gene locus existed, but other gene loci were lost (52.1% vs 32.0%). The hormone levels were similar in patients with sY1192 deletion alone and in those with sY1192 deletion and other types of microdeletions in the presence of the sY1192 locus. After multiple intracytoplasmic sperm injection (ICSI) attempts, the pregnancy rate of spouses of men with sY1192-independent deletions was similar to that of other types of microdeletions, but the fertilization and cleavage rates were higher. We observed that eight deletion patterns were observed for sY1192 microdeletions of AZFb/c, dominated by the independent deletion of sY1192. After ICSI, the fertilization rate and cleavage rate of the sY1192-independent microdeletion were higher than those of other Y chromosome microdeletion types, but there was no significant difference in pregnancy outcomes.

Genetic etiological spectrum of sperm morphological abnormalities.

Male infertility manifests in the form of a reduction in sperm count, sperm motility, or the loss of fertilizing ability. While the loss of sperm production can have mixed reasons, sperm structural defects, cumulatively known as teratozoospermia, have predominantly genetic bases. The aim of the present review is to undertake a comprehensive analysis of the genetic mutations leading to sperm morphological deformities/teratozoospermia. We undertook literature review for genes involved in sperm morphological abnormalities. The genes were classified according to the type of sperm defects they cause and on the basis of the level of evidence determined by the number of human studies and the availability of a mouse knockout. Mutations in the SUN5, CEP112, BRDT, DNAH6, PMFBP1, TSGA10, and SPATA20 genes result in acephalic sperm; mutations in the DPY19L2, SPATA16, PICK1, CCNB3, CHPT1, PIWIL4, and TDRD9 genes cause globozoospermia; mutations in the AURKC gene cause macrozoospermia; mutations in the WDR12 gene cause tapered sperm head; mutations in the RNF220 and ADCY10 genes result in small sperm head; mutations in the AMZ2 gene lead to vacuolated head formation; mutations in the CC2D1B and KIAA1210 genes lead to pyriform head formation; mutations in the SEPT14, ZPBP1, FBXO43, ZCWPW1, KATNAL2, PNLDC1, and CCIN genes cause amorphous head; mutations in the SEPT12, RBMX, and ACTL7A genescause deformed acrosome formation; mutations in the DNAH1, DNAH2, DNAH6, DNAH17, FSIP2, CFAP43, AK7, CHAP251, CFAP65, ARMC2 and several other genes result in multiple morphological abnormalities of sperm flagella (MMAF). Altogether, mutations in 31 genes have been reported to cause head defects and mutations in 62 genes are known to cause sperm tail defects.

Radioprotective effects of melatonin therapy against testicular oxidative stress: a systematic review and meta-analysis of rodent models

Background: Radiation exposure is a concern in today’s world, given the widespread use of electronic devices and medical procedures involving ionizing and non-ionizing radiation. Radiations may cause male infertility by inducing oxidative stress in testicular tissue. Melatonin has antioxidant properties. Methods: We systematically reviewed the literature for the studies that have investigated the effects of melatonin therapy on radiation-induced oxidative stress in rodents’ testicular tissue. PubMed, Scopus, and Web of Science were searched for relevant animal trials. Standardized mean difference and 95% confidence intervals were used to pool the data. Subgroup and sensitivity analyses were done. The risk of bias was assessed using SYRCLE tool. Results: Outcomes: histopathology and sperm analyses (testicular apoptotic cells, Johnsen’s testicular biopsy score, seminiferous epithelial height, tubular diameter, sperm motility, viability, count, and morphology, concentration of spermatid, spermatocyte, and spermatogonia), body and testes weights (absolute and relative body and testicular weights), reproductive hormones (serum prolactin, FSH, and testosterone), and oxidative stress tissue markers (TBARS, CAT, GSH, GSH-Px, MDA, SOD, and XO, and total antioxidant capacity). Rats and mice were exposed to electromagnetic radiations (gamma, roentgen, microwave, radiofrequency, and high-power line energy) and particle waves (radioiodine and carbon-ion). Melatonin therapy was significantly associated with improved male reproduction. Conclusion: Radiation exposure harms male fertility, but melatonin, as an antioxidant, is potentially associated with improved male reproductive function in rodents. Inconsistencies in research require further investigations.

DNA fragmentation of sperm and microdeletions in the long arm of the Y chromosome in male infertility patients from private fertilization units of Barquisiemto, Lara State

Abstract Introduction/Objective Figures for infertility area increasing worldwide, with a large share of causes related to the male gender. The objective of this study is to relate the frequency of abnormal sperm DNA fragmentation and the frecuency of microdeletions in the long arm of Y chromosome (Yq) in patients with male infertility from private fertilitation units of Barquisimeto, Lara, during the 2010-2012 period. Methods/Case Report We analyzed 38 samples of semen from infertile male patients to measure DNA fragmentation index (FI) by TUNEL technique, and 36 semen samples from patients with male infertility to measure FI employing SCD method. To dertermine the frecuency of Yq microdeletions by polymerase chain reaction (PCR), samples of peripheral blood from 33 patients with male infertility were evaluated. Among the 38 patients in whom the FI was measured by TUNEL technique, eight(8) of them were also tested for detection of Yq microdeletions, and one (1) of these patients performed SCD test for medical reasons. Results (if a Case Study enter NA) The frecuency of abnormal fragmentation index of sperm DNA, determined by the TUNEL technique in patients with male infertility was 47.37%. The frecuency of abnormal fragmentation index of sperm DNA determoined by SCD method in infertile male patients was 22.22%. And the frecuency of microdeletions of the long arm of the Y chromosome in patients with male infertility was 9.09%. All microdeletions were found at DAZSY208 in AZFc region and in one case there was also detected a microdeletion at DAZSY255. Conclusion It was also showed that, sperm DNA fragmentation is not depending on the existence of Yq microdeletions.

Characterizing the Impact of Dysregulated Micrornas on CRISP3 Isoforms in Male Infertility.

microRNAs (miRNAs) have a serious and dynamic function in spermatogenesis. These molecules have been recognized as crucial parts of the control of gene activity, and their involvement in the regulation of target genes has been extensively studied. This research aimed to determine the expression of CRISP3 and miR-493-5p, miR-204-5p, and miR-182-5p in the seminal plasma fluid and spermatozoa and to examine the relationship between CRISP3 and the mentioned miRNAs in 57 infertile men with Asthenozoospermia (AZ) (n = 19), Teratoasthenozoospermia (TAZ) (n = 19), and Normozoospermia (NZ) (n = 19).The selection of these three miRNAs, miR-493-5p, miR-204-5p, and miR-182-5p, was conducted using computational prediction algorithms. These miRNAs were nominated as CRISP3-associated miRNAs that can target CRISP3. We performed the quantitative real-time polymerase chain reaction (qRT-PCR) method to determine the levels of the studied miRNA expression. In the following stage, the expression of two protein isoforms of CRISP3, targeted by these miRNAs, was quantified using western blotting. The results demonstrate significant differences in the levels of miR-182-5p, miR-204-5p, miR-493-5p, and CRISP3 isoforms among the patient groups. In TAZ individuals, miR-182-5p and miR-204-5p expression decreased, while miR-493-5p expression increased compared to the control samples. Additionally, significant differences were observed in the expression levels of unglycosylated and glycosylated CRISP3 isoforms between the AZ and NZ groups. Correlation analysis revealed associations between miRNA expression and the expression of CRISP3 isoforms in the patient groups. Additionally, there were correlations between the expression of CRISP3 isoforms and sperm motility and morphology. These results offer valuable insights into the underlying molecular processes associated with male infertility.

Establishment of a CIB1 knockout human pluripotent stem cell line via CRISPR/Cas9 genome editing technology

Calcium- and integrin-binding protein 1 (CIB1) has a diverse role in many different cell types and processes, including calcium signaling, migration, adhesion, proliferation, and survival. It is associated with cancer, cardiovascular disease and male infertility. Here, CRISPR/Cas9 genome-editing technology was employed to establish a CIB1 knockout human embryonic stem cell line, which exhibited normal pluripotency and karyotype.

The role of p53 in male infertility.

The tumor suppressor p53 is a transcription factor involved in a variety of crucial cellular functions, including cell cycle arrest, DNA repair and apoptosis. Still, a growing number of studies indicate that p53 plays multiple roles in spermatogenesis, as well as in the occurrence and development of male infertility. The representative functions of p53 in spermatogenesis include the proliferation of spermatogonial stem cells (SSCs), spermatogonial differentiation, spontaneous apoptosis, and DNA damage repair. p53 is involved in various male infertility-related diseases. Innovative therapeutic strategies targeting p53 have emerged in recent years. This review focuses on the role of p53 in spermatogenesis and male infertility and analyses the possible underlying mechanism involved. All these conclusions may provide a new perspective on drug intervention targeting p53 for male infertility treatment.

Male Infertility.

Male Infertility.

Voltage-Dependent Anion Channels in Male Reproductive Cells: Players in Healthy Fertility?

Male infertility affects nearly 50% of infertile couples, with various underlying causes, including endocrine disorders, testicular defects, and environmental factors. Spermatozoa rely on mitochondrial oxidative metabolism for motility and fertilization, with mitochondria playing a crucial role in sperm energy production, calcium regulation, and redox balance. Voltage-dependent anion channels (VDACs), located on the outer mitochondrial membrane, regulate energy and metabolite exchange, which are essential for sperm function. This review offers an updated analysis of VDACs in the male reproductive system, summarizing recent advances in understanding their expression patterns, molecular functions, and regulatory mechanisms. Although VDACs have been widely studied in other tissues, their specific roles in male reproductive physiology still remain underexplored. Special attention is given to the involvement of VDAC2/3 isoforms, which may influence mitochondrial function in sperm cells and could be implicated in male fertility disorders. This update provides a comprehensive framework for future research in reproductive biology, underscoring the significance of VDACs as a molecular link between mitochondrial function and male fertility.

Research advances in inflammation and oxidative stress in varicocele-induced male infertility: a narrative review.

Varicocele, the most common and treatable cause of male infertility, significantly impacts fertility. The pathophysiological mechanisms of varicocele have not been fully understood yet. Recent studies have focused on the pathophysiology of varicocele-induced infertility, highlighting inflammation and oxidative stress as key contributing factors. We reviewed recent research on the roles of inflammation and oxidative stress in the pathophysiology of varicocele and found that they negatively impact semen parameters, spermatogenesis, and testicular and epididymal function. In addition, this article summarizes the related factors of inflammation and oxidative stress caused by varicocele. Finally, a brief consideration on the treatments to address inflammation and oxidative stress is proposed. This review may provide treatment options and targets for varicocele-induced infertility. However, the relationship between inflammation and oxidative stress in varicocele still needs further study.

Future prospects for the advancement of treatment of men with NOA: focus on gene editing, artificial sperm, stem cells, and use of imaging.

Nonobstructive azoospermia (NOA) affects about 60% of men with azoospermia, representing a severe form of male infertility. The current approach to manage NOA primarily involves testicular sperm retrieval methods such as conventional testicular sperm extraction (c-TESE) and microdissection testicular sperm extraction (micro-TESE). While combining testicular sperm retrieval with intracytoplasmic sperm injection (ICSI) offers hope for patients, the overall sperm retrieval rate (SRR) stands at around 50%. In cases where micro-TESE fails to retrieve sperm, limited options, like donor sperm or adoption, can be problematic in certain cultural contexts. This paper delves into prospective treatments for NOA management. Gene editing technologies, particularly clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) protein 9 (CRISPR/Cas9), hold potential for correcting genetic mutations underlying testicular dysfunction. However, these technologies face challenges due to their complexity, potential off-target effects, ethical concerns, and affordability. This calls for research to address key challenges associated with NOA management within the clinical settings. This also necessitate ongoing research essential for developing more sensitive diagnostic tests, validating novel treatments, and customizing current treatment strategies for individual patients. This review concluded that the future of NOA management may entail a combination of these treatment options, tailored to each patient's unique circumstances, providing a comprehensive approach to address NOA challenges.

Metabolomic profiling of human semen in patients with oligospermia using high performance liquid chromatography-tandem mass spectrometry

Male infertility is one of the most common reproductive dysfunctions. Despite oligospermia being a cause of infertility, few studies have been conducted on it. This study aimed to investigate differences in semen metabolic patterns in patients with oligospermia and to identify potential biomarkers associated with oligospermia. Semen samples from oligospermia patients (20 cases) and healthy controls (20 cases) were detected by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and 72 and 89 metabolites were identified as potential markers in positive and negative ion modes, respectively. In addition, the results identified multiple metabolic pathways in patients with oligospermia, such as glycine serine and threonine metabolism, Synthesis and degradation of ketone bodies, Valine, leucine, and isoleucine degradation. These results described unique metabolic characteristics of semen in patients with oligospermia and provided novel insights into the mechanism of the semen disorder.

Semen static oxidation-reduction potential is not helpful in evaluating male fertility.

Infertility affects a significant percentage of couples worldwide, with male infertility contributing substantially in a considerable number of cases. Research indicates that oxidative stress is a critical factor impacting male fertility. To explore the relationship between semen static oxidation-reduction potential (sORP), sperm parameters, and validated biomarkers of oxidative stress in infertile men. This cross-sectional study involved 202 men diagnosed with idiopathic male factor infertility and male partners from couples with unexplained infertility. Multivariable linear regression to query the associations between sORP, sperm parameters, and oxidative aggression biomarkers (lipid peroxidation, mitochondrial membrane potential, annexin V, and sperm DNA fragmentation). SORP has no linear association with any semen analysis parameter. Furthermore, its relationship with validated biomarkers of oxidative stress was inconsistent. sORP was inversely related to lipid peroxidation (multivariable linear regression coefficient: -0.64), positively associated with sperm DNA fragmentation (multivariable linear regression coefficient: 3.20), and unrelated to mitochondrial membrane potential or annexin V. There is no clear or consistent relationship between sORP and validated oxidative aggression biomarkers or sperm parameters. Our findings suggest that sORP is unlikely to be helpful in the evaluation of a male with idiopathic infertility.

Lecithin’s antioxidant properties protect against cyclophosphamide-induced reproductive toxicity and infertility in male rats

Background: Infertility is a prevalent problem that affects 15% of couples globally. Male infertility, which accounts for half of all cases, can be caused by several factors, including aging, drug use, genetic problems, and exposure to environmental toxins. Cyclophosphamide (CP) is a commonly utilized immunosuppressant and anticancer medication that can induce oxidative stress and harm the reproductive system of men. The beneficial effects of antioxidants in mitigating the CP-induced reproductive toxicities are well-documented. Aim: The aim of this study was to assess the effects of lecithin (as an antioxidant) against the CP-induced reproductive toxicity in male rats. Methodology: Thirty Sprague-Dawley male rats were divided into three groups: (i) the negative control group (that received sterile water via the intragastric route for 13 consecutive days), (ii) the positive control group (that received sterile water via the intragastric route for 5 days and, subsequently, a single, intraperitoneal dose of CP on day 6, followed by sterile water via the intragastric route for the next 7 consecutive days), and (iii) the lecithin-treated group (that received lecithin via the intragastric route for 5 days and, subsequently, a single, intraperitoneal dose of CP on day 6, followed by lecithin via the intragastric route for the next 7 consecutive days). Results: Lecithin treatment improved sperm parameters, plasmatic testosterone levels, and glutathione peroxidase, thereby preventing histopathological alterations in the rat testes. Conclusion: Lecithin demonstrated its potential protective effects against reproductive impairments and oxidative stress in the CP-treated rat group, and might prove promising for use in clinical practice as a protective agent against chemotherapy-induced male reproductive toxicity and infertility.