Sperm morphology by strict criteria does not predict clinical pregnancy rate following intra-uterine insemination.

Objective: To determine the impact of abnormal sperm morphology of the pre-washed semen sample on the day of intrauterine insemination (IUI) on clinical pregnancy rates (CPR). Design: Cross sectional retrospective chart review. Setting: Academic fertility center. Patients: Couples undergoing (IUI) from May 2014 to March 2022. Interventions: Sperm morphology, by strict criteria, on the pre-washed IUI sample. Main outcomes Measures: To determine the association of sperm morphology with CPR. Results: Semen analysis reports, including Kruger strict criteria for morphology from the pre-washed IUI sample, were reviewed for 1,059 cycles, comprising 825 total treated couples.Of the total 1,059 cycles,15.1% resulted in clinical pregnancy. When categorized by strict morphology ≥4% (normal morphology), (3%-2%) [mild-moderate teratozoospermia (TZS)], and ≤1% (severe TZS), the CPR was 16%, 13%, and 10%, respectively (p value 0.30). Early spontaneous miscarriage rate was 4% and when stratified by morphology ≥4% (3%-2%), and ≤1%, was 3%, 1%, and 0%, respectively (p value 0.20).In couples with isolated TZS, the pregnancy rate was 16% in the normal morphology group, 14% in the mild-moderate group, and 8% in the severe group. (p value 0.30).In the multivariate logistic regression, sperm morphology, mild/moderate TZS vs normal forms (OR = 0.99, 95% CI [0.94-1.1]), severe TZS vs normal forms (OR = 0.98, 95% CI [0.0.83-1.1]), was not a predictor of CPR. The Pre-wash TMSC (OR = 1.0, 95% CI [0.996-1.00]) was also not predictive of CPR.The only predictive factor of CPR in IUI was the PWTMSC (OR = 1.03, 95%CI [1.00-1.06). Conclusions: The morphology of the pre-washed sample on the day of IUI did not find a difference in CPR, neither in miscarriage rate following IUI, in couples with normal or abnormal sperm morphology, including severe TZS.Mild, moderate, or severe TZS in the semen sample should not exclude couples to attempt an IUI procedure.

Loss-of-function variant in TDRD6 cause male infertility with severe oligo-astheno-teratozoospermia in human and mice.

Oligo-astheno-teratozoospermia (OAT) is a common cause of male infertility, but the genetic basis of most OAT cases is still unknown. Here, one homozygous loss-of-function (LOF) variant in TDRD6, c.G1825T/p.Gly609X, was identified in an infertile patient with severe OAT by whole-exome sequencing (WES) and Sanger confirmation. Furthermore, Tdrd6-mutant mice (p.Gly615X; equivalent to p.Gly609X in human TDRD6) were generated. Remarkably, the Tdrd6-mutated mice mimicked the severe OAT symptoms of the patient. In addition, the architecture of chromatoid bodies (CBs) were disrupted in round spermatids from Tdrd6-mutant mice, leading to blocked spermatogenesis in the round spermatids. The assembly of PIWIL1, TDRD1, TDRD7 and DDX25 in CBs was disturbed in the Tdrd6-mutant mice. Applying immunoprecipitation-mass spectrometry (IP-MS), we identified some TDRD6-interacting partners, including CB proteins TDRD7, MAEL and PCBP1. Moreover, we described the assisted reproductive technology (ART) outcomes of the infertile patient and his partner. Altogether, our findings provide necessary evidences to support the idea that the homozygous LOF variant in TDRD6 induces male infertility with severe OAT, suggesting that TDRD6 could be a useful genetic diagnostic target for male infertility.

Utility of exome sequencing in primary spermatogenic disorders: From research to diagnostics.

BACKGROUND: Primary spermatogenic disorders represent a severe form of male infertility whereby sperm production is impaired due to testicular dysfunction, leading to reduced quality or quantity of spermatozoa. Gene-centered research has certainly demonstrated the importance of the genetic factor in the etiology of both poor sperm morphology or motility and reduced sperm count. In the last decade, next-generation sequencing has expanded the research to whole exome which has transformed our understanding of male infertility genetics, but uncertainty persists in its diagnostic yield, especially in large unrelated populations. OBJECTIVE: To evaluate the utility of exome sequencing in detecting genetic factors contributing to various traits of primary spermatogenic disorders, which is a crucial step before interpreting the diagnostic yield of the platform. MATERIALS AND METHODS: We manually curated 415 manuscripts and included 19 research studies that predominantly performed whole exome sequencing in cohorts of unrelated cases with primary spermatogenic defects. RESULTS: The detection rate, defined as the fraction of cases with an identifiable genetic cause, typically remained below 25% for quantitative defects of spermatozoa, whereas improved rates were observed for traits of abnormal sperm morphology/motility and in populations enriched with consanguineous families. Unlike the quantitative defects, the genetic architecture of the qualitative issues of spermatozoa featured a small number of recurrent genes describing a large fraction of studied cases. These observations were also in line with the lower biological complexity of the pathways affected by the reported genes. DISCUSSION AND CONCLUSIONS: This review demonstrates the variability in detection rates of exome sequencing across semen phenotypes, which may have an impact on the expectations of the diagnostic yield in the clinical setting.

Comparative analysis of calcium-sensing receptor (CaSR) expression and function in normal and abnormal human sperm and spermatogenic cells.

The calcium-sensing receptor (CaSR) is a critical mediator of calcium homeostasis in various tissues. Its role in human reproduction, especially in sperm function and male fertility, remains not fully elucidated. This study investigates the expression patterns of CaSR in normal and abnormal sperm and spermatogenic cells and evaluates its potential effect on sperm motility and morphology. Using immunohistochemistry (IHC), quantitative PCR (qPCR), we assessed the expression levels of CaSR in normal sperm, spermatogonia, and cases of asthenozoospermia, oligozoospermia, and teratozoospermia. In vitro functional assays were performed to analyze the effects of CaSR modulation on sperm motility under varying conditions, including the presence of specific CaSR agonists and antagonists. Our study revealed distinct patterns of CaSR expression in normal sperm and spermatogonia compared with those in abnormal sperm samples, particularly in cases of asthenozoospermia, oligozoospermia, and teratozoospermia. A marked decrease in CaSR expression was evident in these abnormal samples, highlighting its significance in normal sperm functionality. Functional assays further elucidated the role of CaSR in sperm motility. Activation of CaSR through specific agonists enhanced sperm motility, while inhibition by antagonists led to reduced motility. Our findings suggest that CaSR plays a significant role in maintaining sperm functionality and that changes in its expression may be associated with male infertility. These insights into the molecular underpinnings of sperm physiology highlight CaSR as a potential therapeutic target for treating certain forms of male infertility.

[Causal relationship between relative abundance of gut microbiota and teratozoospermia: A two-sample Mendelian randomization analysis].

OBJECTIVE: To explore the potential causal relationship between gut microbiota and teratozoospermia. METHODS: We searched the database of Genome-Wide Association Study (GWAS) for gut microbiota- and teratozoospermia-related data. We used gut microbiota as an exposure factor, determined the instrumental variables according to the GWAS data on 18 340 participants released by the MiBioGen Alliance, and derived the outcome variables from the European data on teratozoospermia, with a sample size of 85 716, including 915 cases and 209 006 controls. Using inverse-variance weighting (IVW), MR-Egger regression and the weighted median estimator (WME), we performed two-sample Mendelian randomization (MR) analysis on the retrieved data, and estimated the causal relationship between gut microbiota and teratozoospermia based on the ß value. RESULTS: Two-sample MR analysis indicated that the class Erysipelotrichia, family Erysipelotrichaceae, family Streptococcaceae, genus Coprococcusl, genus Ruminococcaceae UCG009, genus Streptococcus, order Clostridialesm and order Erysipelotrichales were causally related with the increased risk, while the family Porphyromonadaceae with the decreased risk of teratozoospermia. CONCLUSION: The class Erysipelotrichia, family Erysipelotrichaceae, family Streptococcaceae, genus Coprococcusl, genus Ruminococcaceae UCG009, genus Streptococcus, order Clostridialesm and order Erysipelotrichales are one of the causes of teratozoospermia, related to the increased risk of the condition, while the family Porphyromonadaceae has a protective effect on sperm morphology, reducing the risk of teratozoospermia.

Phenotypic continuum and poor intracytoplasmic sperm injection intracytoplasmic sperm injection prognosis in patients harboring HENMT1 variants.

BACKGROUND: Small RNAs interacting with PIWI (piRNAs) play a crucial role in regulating transposable elements and translation during spermatogenesis and are essential in male germ cell development. Disruptions in the piRNA pathway typically lead to severe spermatogenic defects and thus male infertility. The HENMT1 gene is a key player in piRNAs primary biogenesis and dysfunction of HENMT1 protein in meiotic and haploid germ cells resulted in the loss of piRNA methylation, piRNA instability, and TE de-repression. Henmt1-knockout mice exhibit a severe oligo-astheno-teratozoospermia (OAT) phenotype, whereas patients with HENMT1 variants display more severe azoospermia phenotypes, ranging from meiotic arrest to hypospermatogenesis. Through whole-exome sequencing (WES) of infertile patient cohorts, we identified two new patients with variants in the HENMT1 gene presenting spermatozoa in their ejcaulate, providing us the opportunity to study spermatozoa from these patients. OBJECTIVES: Investigate the spermatozoa of two patients harboring an HENMT1 variant to determine whether or not these scarce spermatozoa could be used with assisted reproductive technologies. MATERIALS AND METHODS: HENMT1 variants identified by WES were validated through Sanger sequencing. Comprehensive semen analysis was conducted, and sperm cells were subjected to transmission electron microscopy for structural examination, in situ hybridization for aneuploidy assessment, and aniline blue staining for DNA compaction status. Subsequently, we assessed their suitability for in vitro fertilization using intracytoplasmic sperm injection (IVF-ICSI). RESULTS: Our investigations revealed a severe OAT phenotype similar to knockout mice, revealing altered sperm concentration, mobility, morphology, aneuploidy and nuclear compaction defects. Multiple IVF-ICSI attempts were also performed, but no live births were achieved. DISCUSSION: We confirm the crucial role of HENMT1 in spermatogenesis and highlight a phenotypic continuum associated with HENMT1 variants. Unfortunately, the clinical outcome of these genetic predispositions remains unfavorable, regardless of the patient's phenotype. CONCLUSION: The presence of spermatozoa is insufficient to anticipate ICSI pregnancy success in HENMT1 patients.

Innovative all-in-one exome sequencing strategy for diagnostic genetic testing in male infertility: Validation and 10-month experience.

BACKGROUND: Current guidelines indicate that patients with extreme oligozoospermia or azoospermia should be tested for chromosomal imbalances, azoospermia factor (AZF) deletions and/or CFTR variants. For other sperm abnormalities, no genetic diagnostics are recommended. OBJECTIVES: To determine whether exome sequencing (ES) with combined copy number variant (CNV) and single nucleotide variant (SNV) analysis is a reliable first-tier method to replace current methods (validation study), and to evaluate the diagnostic yield after 10 months of implementation (evaluation study). MATERIALS AND METHODS: In the validation study, ES was performed on DNA of patients already diagnosed with AZF deletions (n = 17), (non-)mosaic sex chromosomal aneuploidies or structural chromosomal anomalies (n = 37), CFTR variants (n = 26), or variants in known infertility genes (n = 4), and 90 controls. The data were analyzed using our standard diagnostic pipeline, with a bioinformatic filter for 130 male infertility genes. In the evaluation study, results of 292 clinical exomes were included. RESULTS: All previously reported variants in the validation cohort, including clinically relevant Y-chromosomal microdeletions, were correctly identified and reliably detected. In the evaluation study, we identified one or more clinically relevant genetic anomalies in 67 of 292 of all cases (22.9%): these included aberrations that could have been detected with current methods in 30 of 67 patients (10.2% of total), (possible) (mono)genetic causes in the male infertility gene panel in 28 of 67 patients (9.6%), and carriership of cystic fibrosis in nine of 67 patients (3.1%). CONCLUSION: ES is a reliable first-tier method to detect the most common genetic causes of male infertility and, as additional genetic causes can be detected, in our evaluation cohort the diagnostic yield almost doubled (10.2%-19.8%, excluding CF carriers). A genetic diagnosis provides answers on the cause of infertility and helps the professionals in the counseling for treatment, possible co-morbidities and risk for offspring and/or family members. Karyotyping will still remain necessary for detecting balanced translocations or low-grade chromosomal mosaicism.

Atypical structure of the nuclear membrane, distribution of nuclear pores and lamin B1 in spermatozoa of patients with complete and partial globozoospermia.

Globozoospermia is a form of male infertility characterized by spermatozoa with spherical heads lacking acrosomes. The aim of this study was to evaluate ultrastructural and molecular defects in different types of globozoospermia. Semen samples from 12 infertile patients (9 with complete globozoospermia and 3 with partial globozoospermia) and 10 normozoospermic men (control) were examined by transmission electron microscopy and immunocytochemistry with antibodies against lamin B1. The presence of lamin A and progerin was assessed by reverse transcription-PCR. Whole exome sequencing was performed in three patients. In semen samples with complete and partial globozoospermia, lamin B1 was observed at the periphery of sperm nuclei, whereas lamin A and progerin were absent. Nuclear envelope pores were found in spermatozoa from both patient groups, regardless of morphology and chromatin condensation, in contrast to the control group. Non-condensed chromatin was present in 51%-81% of cases of complete globozoospermia and in 36%-79% of cases of partial globozoospermia. Homozygous DPY19L2 and SPATA16 variants were identified in two patients with partial globozoospermia and one patient with complete globozoospermia. An atypical nuclear membrane with abnormal nuclear pore distribution and lamin B1 localization was observed in spermatozoa from patients with both complete and partial globozoospermia. The genetic defects in the DPY19L2 and SPATA16 genes detected in patients from both globozoospermic groups suggest a generalized disruption of nuclear structure in globozoospermia, highlighting the genetic and phenotypic similarities between complete and partial globozoospermia.

CCDC189 depletion leads to oligo-astheno-teratozoospermia and male infertility in mice.

In male reproductive system, proteins containing the coiled-coil domain (CCDC) are predominantly expressed in specific regions including the testis, epididymis, seminal vesicle, and prostate. They play a vital role in centriole formation, sperm motility and flagellar development in male gametes. Despite being highly expressed in the testis, the exact physiological function of the coiled-coil domain-containing 189 (Ccdc189) gene remain largely unclear. Our research provides a comprehensive and detailed investigation into the localization of CCDC189 protein within the testis seminiferous tubules. CCDC189 specifically expressed in spermatocytes, round spermatids and elongating spermatids in mouse testis. The deletion of Ccdc189 in mouse leads to male infertility, characterized by significantly reduced sperm counts and motility. Abnormally shaped spermatozoa with irregular tails, exhibiting shortened and twisted morphology, were observed in the seminiferous tubules. Electron microscopy revealed disordered and missing peripheral microtubule doublets (MTD) and outer dense fibers (ODF) in the sperm flagella, accompanied by a consistent absence of central pairs (CP). The knockout of Ccdc189 resulted in oligo-astheno-teratozoospermia, which is characterized by low sperm count and reduced sperm motility and abnormal morphology. Furthermore, we identified poly(A)-binding protein cytoplasmic 1 (PABPC1) and PABPC2 as interacting proteins with CCDC189. These proteins belong to the poly(A)-binding protein (PABP) family and are involved in regulating mRNA translational activity in spermatogenic cells by specifically binding to poly(A) tails at the 3' ends of mRNAs.

SPEM1 Gene Mutation in a Case with Sperm Morphological Defects Leading to Male Infertility.

The present study aimed at identifying the genetic mutation responsible for teratozoospermic infertility in a case with coiled sperm tails. A 33-year-old infertile male was diagnosed with teratozoospermic infertility, with sperm head in coiled (HIC) tail as the most common deformity. We employed whole exome sequencing to identify the genetic cause in this case. Exome sequencing data was filtered using the following criteria: MAF (< 0.003), ALFA project (< 0.001), 1000 Genomes (< 0.003), Granthem (> 50), Polyphen-2 (> 0.70), SIFT (< 0.03), and PhyloP (> = 0) scores. Shortlisted variants were looked in the in-house 29 exomes data available with us, and the variants that affected conserved amino acid residues or led to insertion/deletion or to protein-truncation with a Combined Annotation Dependent Depletion (CADD) score ≥ 10 were shortlisted. The variants thus populated were prioritized according to their roles in spermiogenesis. The study identified a heterozygous mutation c.826C > T (Arg276Trp) in the SPEM1 gene as a potential pathogenic variant that led to teratozoospermic infertility in the case under investigation. The mutation had a minor allele frequency of 0.00008176 in the gnomAd database and was absent in the Indian Genome Variations database. This is the first human study reporting a mutation in the SPEM1 gene as a cause of coiled sperm tails.

Genetic Causes of Qualitative Sperm Defects: A Narrative Review of Clinical Evidence.

Several genes are implicated in spermatogenesis and fertility regulation, and these genes are presently being analysed in clinical practice due to their involvement in male factor infertility (MFI). However, there are still few genetic analyses that are currently recommended for use in clinical practice. In this manuscript, we reviewed the genetic causes of qualitative sperm defects. We distinguished between alterations causing reduced sperm motility (asthenozoospermia) and alterations causing changes in the typical morphology of sperm (teratozoospermia). In detail, the genetic causes of reduced sperm motility may be found in the alteration of genes associated with sperm mitochondrial DNA, mitochondrial proteins, ion transport and channels, and flagellar proteins. On the other hand, the genetic causes of changes in typical sperm morphology are related to conditions with a strong genetic basis, such as macrozoospermia, globozoospermia, and acephalic spermatozoa syndrome. We tried to distinguish alterations approved for routine clinical application from those still unsupported by adequate clinical studies. The most important aspect of the study was related to the correct identification of subjects to be tested and the correct application of genetic tests based on clear clinical data. The correct application of available genetic tests in a scenario where reduced sperm motility and changes in sperm morphology have been observed enables the delivery of a defined diagnosis and plays an important role in clinical decision-making. Finally, clarifying the genetic causes of MFI might, in future, contribute to reducing the proportion of so-called idiopathic MFI, which might indeed be defined as a subtype of MFI whose cause has not yet been revealed.

Application of Intracytoplasmic Morphologically Selected Sperm Injection (IMSI) on a Teratozoospermic Patient and Its Effect on the In-Vitro Fertilization (IVF) Outcome.

Infertility, defined as the inability to conceive after 12 months of unprotected sexual activity, affects millions globally. Approximately 80% of cases have identifiable causes, including endometriosis, tubal obstruction, ovulatory dysfunction, and male sperm abnormalities. Lifestyle factors, such as smoking and obesity, also impact fertility. Sperm morphology, a key factor in male infertility, often presents as teratozoospermia, with defects in the head, midpiece, or tail. Poor ovarian reserve, indicated by low anti-mullerine hormone (AMH) and antra-follicular count (AFC) values, contributes to female infertility, often exacerbated by age-related factors. Elevated follicle-stimulating hormone (FSH) levels further diminish oocyte quantity and quality. Intracytoplasmic Sperm Injection (ICSI), a micromanipulation technique aiding infertile couples, may face challenges in detecting subtle sperm morphology defects. Advanced methods like Motile Sperm Organelle Morphological Examination (MSOME) and Intracytoplasmic Morphologically Selected Sperm Injection (IMSI) under high magnification enhance sperm selection accuracy. We present the case of a 36-year-old woman and her 42-year-old husband who sought assistance after seven years of infertility. Previous Intrauterine injection (IUI) and ICSI attempts failed due to the wife's low ovarian reserve and elevated FSH, compounded by the husband's teratozoospermia. Their earlier In-Vitro Fertilization (IVF) experience yielded a single poor-quality oocyte, hindering blastocyst formation. Investigations revealed the wife's poor AFC, AMH of 0.033ng/ml, and FSH at 24IU/L. Her medical history included hypertension and gallbladder removal. The husband exhibited 98% defective sperm, devoid of a substance abuse history. The wife's family had a polycystic ovarian syndrome (PCOS) history, and her low AMH and AFC yielded only three poor-quality oocytes during the current assessment. Oocytes were retrieved, and sperm were selected with the help of IMSI. After ICSI, the patient successfully conceived.

Isolated teratozoospermia: revisiting its relevance in male infertility: a narrative review.

Background and Objective: Basic semen analysis is the first step in the evaluation of male infertility. It includes an assessment of sperm morphology which is believed to reflect on overall spermatogenesis and sperm function. Teratozoospermia, defined as abnormal sperm morphology, is frequently present in association with severe oligoasthenozoospermia, but isolated teratozoospermia (in the presence of normal counts and motility) is a poorly understood clinical entity with conflicting implications in terms of fertility potential and treatment strategies. The following paper aims to: (I) discuss the classification of sperm morphology, causes, and molecular mechanism of teratozoospermia; (II) analyze the clinical significance and potential treatment options of isolated teratozoospermia as a cause of male infertility and a predictor of fertility outcome; and (III) provide a SWOT (strengths, weaknesses, opportunities, and threats) analysis based on the existing literature on this topic. Methods: A comprehensive search from database inception to 25 April 2023 was conducted in PubMed for relevant papers relating to isolated teratozoospermia in male infertility. Finally, seven systematic reviews/reviews/meta-analyses and 81 original articles were synthesized into the current narrative review. Key Content and Findings: Classification of sperm morphology has evolved significantly since the first edition of the World Health Organization (WHO) Manual of Human Semen Analysis. Kruger's strict criteria are the most used classification and have been shown to correlate with fertility outcomes. There are many causes of teratozoospermia including genetic and environmental factors and physical conditions like varicocele. Teratozoospermia correlates with sperm DNA damage, elevated oxidative stress, low antioxidant function, and apoptotic alterations, which can result in impaired spermatozoa function and lower pregnancy rates. However, the clinical correlation between teratozoospermia and assisted reproductive technology (ART) outcome shows conflicting data with recent meta-analyses suggesting that isolated teratozoospermia was not associated with poor fertility outcomes from ART and that intrauterine insemination (IUI) can be an effective option even in the presence of teratozoospermia. There is very limited data on effective therapeutic options to treat idiopathic isolated teratozoospermia. The opportunity for future research is huge to fill the gap in the medical literature on this topic. Conclusions: Contemporary literature on isolated teratozoospermia shows conflicting results in terms of its actual clinical implication in male infertility and the utility of available treatment options. Further research is warranted on this clinical entity to improve sperm function and future paternity.

Polimorfismo Ser326Cis de la 8-oxoguanina ADN glucosilasa 1 (OGG1) en hombres con teratozoospermia / Ser326Cys polymorphism of 8-oxoguanine DNA glycosylase 1 (OGG1) in men with teratozoospermia

Resumen Antecedentes: El incremento seminal de especies reactivas de oxígeno (ERO) se ha vinculado con la oxidación del ADN y anormalidades en la morfología espermática. La enzima 8-oxoguanina ADN glucosilasa 1 (OGG1) repara la oxidación del ADN. Sin embargo, la presencia del polimorfismo en la OGG1 que involucra cambio de citocina (C) por guanina (G), resultando la sustitución de una cisteína por una serina en el codón 326 (Ser326Cis), ha demostrado disminución en la reparación del ADN oxidado. Estudios del polimorfismo Ser326Cis en hombres españoles y asiáticos con infertilidad demostraron que el alelo G(Cis) incrementa las ERO, impactando en la infertilidad y en la teratozoospermia. Objetivo: Conocer la prevalencia del polimorfismo Ser326Cis de OGG1 en pacientes con teratozoospermia. Método: Se analizaron parámetros espermáticos y el polimorfismo Ser326Cis de OGG1 de 81 muestras de semen con teratozoospermia. Resultados: Los genotipos detectados fueron Ser326Ser(CC) 43%, Ser326Cis(CG) 41% y Cis326Cis(GG) 16%. La frecuencia del alelo G(Cis) fue de 0.4, valor mayor a la frecuencia reportada en las bases de datos disponibles para poblaciones americanas (0.21-0.29), los parámetros espermáticos no se relacionaron con el polimorfismo Ser326Cis. Conclusión: El alelo G(Cis) es un factor que contribuye a la infertilidad.

Abstract Background: The increase in seminal reactive oxygen species (ROS) has been linked to DNA oxidation and abnormalities in sperm morphology. The enzyme 8-oxoguanine DNA glycosylase 1 (OGG1) repairs DNA oxidation. However, the presence of the polymorphism in OGG1 that involves a change of cytokine (C) to guanine (G) resulting in the substitution of a cystine for serine at codon 326 (Ser326Cys) has shown a decrease in the repair of oxidized DNA. Studies of the Ser326Cys polymorphism in Spanish and Asian men with infertility demonstrated that the G(Cys) allele increases ROS, impacting infertility and teratozoospermia. Objective: To know the prevalence of the Ser326Cys polymorphism of OGG1 in patients with teratozoospermia. Method: Sperm parameters and the Ser326Cys polymorphism of OGG1 were analyzed from 81 semen samples. Results: The genotypes detected were Ser326Ser(CC) 43%, Ser326Cys(CG) 41%, and yis326Cys(GG) 16%. The frequency of the G allele (Cys) was 0.4, a value higher than the frequency reported in the databases available for American populations (0.21-0.29), the sperm parameters were not related to the Ser326Cys polymorphism. Conclusion: The G (Cys) allele is a factor that contributes to infertility.

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.

Is varicocoelectomy indicated in infertile men with isolated teratozoospermia? a systematic review and meta-analysis.

BACKGROUND: Clinical palpable varicocoeles in conjunction with isolated teratozoospermia are rarely observed. Therefore, the effects of varicocoelectomy on sperm morphology are not clear. The aim of this meta-analysis is to compile studies that assess the effectiveness of varicocoelectomy in isolated teratozoospermia to reach a more consistent and reliable conclusion. MATERIAL-METHODS: The present meta-analysis was registered to PROSPERO (CRD42023467933). We utilized the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guideline to report the outcomes. Articles published before 1 October 2023 were included in the study. The search terms used were teratozoospermia, isolated teratozoospermia, varicocoelectomy for isolated teratozoospermia, and semen analysis after varicocoelectomy in isolated teratozoospermia. RESULTS: We identified 1,013 studies in full publications or abstracts using the methodology and the search terms. Five studies were included for systematic review, while four were included for meta-analysis. The five studies (10-14) included 348 patients aged 18-44 years. The pooled analysis revealed a significant improvement in sperm morphology in isolated teratozoospermia patients undergoing varicocoelectomy (Q = 199.42, p < 0.0001; I2  = 98.49%). The pooled analysis revealed no significant improvement in sperm concentration in isolated teratozoospermia patients undergoing varicocoelectomy (Q = 5.69, p = 0.058; I2  = 64.85%). Three of the examined studies provided information regarding pregnancy rate and it was high in all studies. According to the Newcastle-Ottowa scale (NOS) assessment, the total quality score of all studies was 7. The funnel plot test demonstrated a visible asymmetry, and Begg and Mazumdar's rank correlation test confirmed the publication bias (p = 0.04). DISCUSSION: Varicocoelectomy can be an effective and reliable treatment option in patients with isolated morphology abnormalities and clinically palpable varicocoele. CONCLUSION: This meta-analysis reported that varicocoelectomy may increase pregnancy rates by improving semen parameters in infertile men with isolated teratozoospermia, although this conclusion requires further evidence.

Novel variations in TENT5D lead to teratozoospermia in infertile patients.

PURPOSE: Teratozoospermia is the main pathogenic factor of male infertility. However, the genetic etiology of teratozoospermia is largely unknown. This study aims to clarify the relationship between novel variations in TENT5D and teratozoospermia in infertile patients. MATERIALS AND METHODS: Two infertile patients were enrolled. Routine semen analysis of patients and normal controls was conducted with the WHO guidelines. Whole-exome sequencing (WES) was conducted to identify pathogenic variants in the two patients. Morphology and ultrastructure analysis of spermatozoa in the two patients was determined by Papanicolaou staining, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The functional effect of the identified variants was analyzed by immunofluorescence staining and western blotting. The expression of TENT5D in different germ cells was detected by immunofluorescence staining. RESULTS: Two new hemizygous variations, c.101C > T (p.P34L) and c.125A > T (p.D42V), in TENT5D were detected in two patients with male infertility. Morphology analysis showed abnormalities in spermatozoa morphology in the two patients, including multiple heads, headless, multiple tails, coiled, and/or bent flagella. Ultrastructure analysis showed that most of the spermatozoa exhibited missing or irregularly arranged '9+2' structures. Further functional experiments confirmed the abrogated TENT5D protein expression in patients. In addition, both p.P34L and p.D42V substitutions resulted in a conformational change of the TENT5D protein. We precisely analyzed the subcellular localization of TENT5D in germ cells in humans and mice. And we found that TENT5D was predominantly detected in the head and flagellum of elongating spermatids and epididymal spermatozoa. CONCLUSIONS: Our results showed further evidence of a relationship between TENT5D mutation and human male infertility, providing new genetic insight for use in the diagnosis and treatment of male infertility.

Splicing Mutation in DNALI1 Causes Male Infertility with Severe Oligoasthenoteratozoospermia in Humans.

Oligo-astheno-teratozoospermia (OAT), which is a common cause of male infertility, can be caused by genetic factors. This study reports on a case of a male patient suffering from infertility concomitant with OAT. Whole-exome sequencing (WES) confirmed the presence of a homozygous variant (NM_003462: c.464-1G > A) in the DNALI1 gene via Sanger sequencing. Immunofluorescence staining demonstrated that the DNALI1 signal was nearly undetectable in the patient's sperm. Bioinformatics analysis revealed that this mutation could reverse the splicing of the exon 4 acceptor splice site. A minigene experiment was performed to verify the mutation and the results confirmed that the mutation disrupted the splicing. Our findings show that this rare mutation in DNALI1 contributes to male infertility and OAT in humans, thereby expanding our understanding of the causes and pathogenesis of male infertility. This knowledge facilitates genetic counseling, clinical diagnosis, and therapeutic development of male infertility.

The association between levels of samarium, hafnium, tungsten and rhenium in seminal plasma and the risk of idiopathic oligo-astheno-teratozoospermia in men of childbearing age.

Oligo-astheno-teratozoospermia (OAT) is a global public health problem, which affects 30% men of childbearing age. Meanwhile, with the rapid development of industry and economy, the contents of rare earth elements (REEs) in the environment are increasing. However, little is known about the associations between REEs levels and OAT risk. To evaluate the associations between the levels of four REEs (samarium (Sm), hafnium (Hf), tungsten (W), rhenium (Re)) in seminal plasma and OAT risk, from October 2021 to November 2022, semen samples from 924 men of childbearing age (460 controls and 464 cases) were collected from the reproductive center of the First Affiliated Hospital of Anhui Medical University. Inductively coupled plasma-mass spectrometry (ICP-MS) was used to measure the levels of Sm, Hf, Re and W in seminal plasma. Bayesian kernel machine regression (BKMR) was conducted to explore the joint effects of levels of four REEs in seminal plasma on the risk of OAT and select the one exerting a major role; generalized linear regression models (GLM) with log link function were employed to investigate the association of every REE level in seminal plasma and OAT risk; sankey diagram and linear regression models were utilized to describe the associations between the levels of four REEs and the indexes of sperm quality. The levels of four REEs in seminal plasma were higher in the case group than levels in the control group (pSm = 0.011, pHf = 0.040, pW = 0.062, pRe = 0.001, respectively). In BKMR analysis, the OAT risk increased when the overall levels of four REEs were higher than their 55th percentile compared to all of them at their 50th percentile, and Re level played a major role in the association. Additionally, Re level in seminal plasma was positively associated with  the OAT risk in the single element model after adjustment of covariates (medium vs. low: OR (95% CI) = 1.55 (1.10, 2.18); high vs. low: OR (95% CI) = 1.69 (1.18, 2.42)). Lastly, the sankey diagram and linear regression models revealed that Sm level was negatively associated with the PR%, total sperm count and total progressively motile sperm count; Hf level was negatively associated with the PR%; W and Re levels were negatively associated with the PR% and total motility, and Re level was positively associated with abnormal morphology rate. Men of childbearing age with OAT had higher levels of Sm, Hf and Re in seminal plasma than those in the control group. An increasing trend for the OAT risk was observed with an increase in mixture levels of Sm, Hf, W and Re, and Re exposure level played a major role in the association whether in BKMR model or single element model. Additionally, the levels of these four REEs were negatively associated with the indexes of sperm quality.

Deleterious genetic changes in AGTPBP1 result in teratozoospermia with sperm head and flagella defects.

Approximately 10%-15% of couples worldwide are infertile, and male factors account for approximately half of these cases. Teratozoospermia is a major cause of male infertility. Although various mutations have been identified in teratozoospermia, these can vary among ethnic groups. In this study, we performed whole-exome sequencing to identify genetic changes potentially causative of teratozoospermia. Out of seven genes identified, one, ATP/GTP Binding Protein 1 (AGTPBP1), was characterized, and three missense changes were identified in two patients (Affected A: p.Glu423Asp and p.Pro631Leu; Affected B: p.Arg811His). In those two cases, severe sperm head and tail defects were observed. Moreover, AGTPBP1 localization showed a fragmented pattern compared to control participants, with specific localization in the neck and annulus regions. Using murine models, we found that AGTPBP1 is localized in the manchette structure, which is essential for sperm structure formation. Additionally, in Agtpbp1-null mice, we observed sperm head and tail defects similar to those in sperm from AGTPBP1-mutated cases, along with abnormal polyglutamylation tubulin and decreasing △-2 tubulin levels. In this study, we established a link between genetic changes in AGTPBP1 and human teratozoospermia for the first time and identified the role of AGTPBP1 in deglutamination, which is crucial for sperm formation.