Reproductive Biology and Endocrinology最新文献

Non-obstructive azoospermia (NOA) is one of the most severe manifestations of male infertility, accounting for up to 70% of azoospermic cases and affecting approximately 1% of the male population. Advances in genomics and epigenetics have transformed our understanding of NOA from a primarily idiopathic condition into a biologically heterogeneous disorder driven by diverse molecular mechanisms. This review synthesizes the current knowledge of the genetic and epigenetic landscape of NOA, integrating chromosomal abnormalities, single-gene mutations, and non-coding RNA (ncRNA) dysregulation. First, we systematically examine classical and emerging chromosomal defects-including karyotype anomalies, Y-chromosome microdeletions, and structural rearrangements-that disrupt meiotic pairing and chromatin organization. Next, we explore syndromic and non-syndromic monogenic mutations affecting meiotic regulators, DNA repair factors, transcription regulators, and chromatin remodelers. Particular emphasis is placed on recently identified genes such as SYCP1, SYCE1 and HORMAD1, whose pathogenic variants are frequently linked to spermatogenic arrest. We then discuss the expanding role of ncRNAs-including microRNAs, PIWI-interacting RNAs, long non-coding RNAs, and circular RNAs-in regulating germ cell apoptosis, transposon silencing, and epigenetic reprogramming. Furthermore, we highlight the translational potential of these molecular insights (including gene variants, ncRNAs and protein) in clinical applications. Genotype-guided sperm retrieval, non-invasive biomarkers, and multi-omic approaches are discussed as promising tools to improve diagnosis and treatment. Moreover, we summarize current and emerging strategies for the treatment and fertility preservation of NOA. Finally, we identify persisting challenges, such as genotypic heterogeneity and incomplete functional validation, and emphasize the need to elucidate interactions between ncRNA and classical genetic pathways to uncover regulatory hierarchies underlying NOA. By integrating molecular genetics with testicular histopathology and clinical phenotypes, this review highlights emerging genetic and ncRNA biomarkers and underscores their potential applications in the clinical management of NOA. Ultimately, a comprehensive understanding of the genetic and epigenetic underpinnings of NOA will be essential for advancing precision diagnostics and improving reproductive outcomes in affected men.

Background: The posttranslational histone modification H3K9me3 is crucial for constitutive heterochromatin (cHC) and supports genome stability and gene regulation during development. This epigenetic mark persists in human sperm post histone-to-protamine transition and is transmitted to the embryo. Although H3K9me3 variability is linked to abnormal sperm parameters, its role in fertilization and embryo development remains unclear. Given its retention in sperm, aberrant H3K9me3 levels may underlie cases of unexplained male infertility.

Objective: Investigate the variability of H3K9me3 levels in sperm from normozoospermic men and assess its association with early embryo development and IVF outcomes.

Material and methods: H3K9me3 and histone H3 levels were quantified by Western blot in surplus sperm from 99 normozoospermic men undergoing IVF-treatment. Patients were stratified into quartiles based on the H3K9me3/H3 ratio. Pre-implantation embryo development was assessed by time-lapse imaging, focusing on nuclear precursor body (NPB) dynamics and morphokinetics. IVF outcomes were reported as cumulative biochemical and ongoing pregnancy rates per ovum pick-up and compared across H3K9me3/H3 quartiles.

Results: H3K9me3/H3 ratios exhibited substantial inter-individual variability among normozoospermic patients. Embryos from the third H3K9me3/H3 ratio quartile (Q3) demonstrated the highest proportion of zygotes with NPB clustering and faster, more consistent development through the first two cleavage divisions compared to other quartiles. A significant non-linear association was found between H3K9me3/H3 ratio and cumulative biochemical pregnancy rates: couples in the lowest quartile (Q1) had significantly reduced odds of biochemical pregnancy compared to Q3 (adjusted OR [95% CI]: 0.30 [0.09-0.97], p = 0.045). No significant association was found for ongoing pregnancy rates.

Discussion and conclusions: This study reveals that sperm H3K9me3 levels vary among normozoospermic men and correlate with early embryo development and biochemical pregnancy rates following IVF. However, no significant association was found with ongoing pregnancy, suggesting that additional mechanisms may determine long-term pregnancy viability. The non-linear relationship between H3K9me3/H3 ratio and embryo development suggests an optimal range for this epigenetic mark. These findings highlight the potential influence of paternal epigenetic variation, undetectable by standard semen analysis, on embryo quality and IVF outcomes. Further studies in larger cohorts are warranted to confirm these findings and clarify underlying mechanisms.

Background: Microdissection testicular sperm extraction (micro-TESE) is an effective method to retrieve sperm from non-obstructive azoospermia (NOA) patients. However, the predictive factors for sperm retrieval rate (SRR) remain confused. The goal of our study was to identify the role of testicular pathological morphometric parameters, including diameter of tubule (DT), height of spermatogenic epithelium (HSE), and thickness of basement-membrane (TBM) in NOA patients, and to develop a predictive model and nomogram to predict SRR based on these morphometric parameters.

Methods: This study involved two cohorts including 406 men with NOA. A retrospective cohort of 313 males with NOA who underwent micro-TESE at Northwest Women's and Children's Hospital (Xi'an, China) were included to build a prediction model of SRR. Then, another retrospective cohort of 93 males with NOA from Ren Ji Hospital (Shanghai, China) were recruited to validate the prediction model. The measurement of testicular morphometric parameters as well as the assessment of Johnsen score and pathological diagnostic types were performed by at least two pathologists. Testicular volumes as well as level of serum hormones including follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone (T) were also measured. Logistic regressions were used to test potential predictors of SRR. Area under curve (AUC) estimates was used to evaluate the predictive accuracy. The validation datasets were used to validate the prediction model by prediction accuracy.

Results: Our study demonstrated that DT and HSE were significantly longer in successful sperm retrieval group than in failed sperm retrieval group. In addition, DT and HSE were positively correlated with Johnsen score, testicular volume, and serum T, while, were negatively correlated with serum FSH and serum LH. On the contrary, TBM demonstrated exact opposite results. Moreover, univariate logistic analyses illustrated that longer DT and HSE was associated with a high SRR, respectively. Further multivariate logistic analyses constructed multi-variables models with better predictive abilities compared with single-variables models. A multi-variables model (predicting score = -0.612-0.018 × DT + 0.040 × HSE + 0.097 × Johnsen score-0.004 × serum FSH) was finally constructed with the best predictive ability (AUC = 0.839, sensitivity = 71.4% specificity = 77.5%, cut-off value = 0.489). A higher predicting score indicated a higher possibility of successful sperm retrieval. The predictive accuracy was 89.25% in the external validation dataset.

Conclusion: We report for the first time that DT and HSE have pretty ability to predict SRR in NOA patients.

Follitropin delta, a recombinant human follicle-stimulating hormone (r-hFSH), is administered using an individualized dosing algorithm based on serum anti-Müllerian hormone (AMH) levels and body weight and offers a different pharmacokinetic (PK) and pharmacodynamic (PD) profile compared to conventional gonadotropins. The retrospective analysis by Eggersmann et al. aimed to compare the cumulative live birth rate (CLBR) of r-hFSH delta versus r-hFSH alfa/beta using data from the German In-vitro Fertilization (IVF) registry (D.I.R.^®; Deutsches IVF-Register), encompassing 113,936 stimulation cycles from women aged 24-45 years between 2017 and 2022. The authors found no statistical differences in oocyte yield, pregnancy rate (PR), and live birth rate (LBR), and an increase in cumulative live birth rate (CLBR) in the group stimulated with r-hFSH delta. The study presents several methodological challenges, such as differences in dose exposure, insufficient adjustment for confounding variables, and the inclusion of diverse patient groups, which may affect the clarity of the comparative effectiveness of the treatments. Additionally, the exclusion of patients who did not undergo frozen embryo transfer may limit the interpretability and generalizability of the findings. While Eggersmann et al. added valuable and meaningful insights into the real-world effectiveness of r-hFSH delta, its conclusions warrant thoughtful consideration. Undertaking a comprehensive methodological assessment strengthens causal inferences drawn from observational data, especially when intended to inform clinical decision-making. This real-world study serves as an important piece of the broader evidence base, contributing to our understanding of assisted reproductive technology (ART) outcomes.

Background: There is a considerable proportion of false positive results when the result of preimplantation genetic testing for aneuploidy is chromosomal mosaicism. The aim of this study was to assess the concordance among clinical trophectoderm biopsy, second trophectoderm biopsy, and inner cell mass biopsy in mosaic human embryos with segmental deletion and evaluate a modified biopsy protocol.

Methods: This retrospective study included 100 pretested blastocysts, which were classified as segmental deletion mosaics with one to two chromosomes were affected, donated by 84 couples in a single, high-volume fertility center in Beijing China. Re-biopsy was taken from the inner cell mass and two symmetrical trophectoderm sites near the inner cell mass in each embryo. Samples from the inner cell mass and one of the two trophectoderm were prepared for modified protocol, which isolated portions into single cells, the cells with normal morphology were collected and cell debris were removed. Re-biopsy samples were analyzed by next-generation sequencing. Main outcome measures were concordance between clinical biopsy and blastocyst, and segmental mosaicism in modified protocol.

Results: Only six (6.5%) of 92 inner cell mass samples presented with concordant chromosomal aberrations, four (4.3%) presented with de novo segmental abnormalities, and 82 (89.1%) did not show any segmental abnormalities. For the trophectoderm samples, 62 (66.7%) of 93 s biopsies and 76 (80%) of 95 modified biopsies did not show any segmental deletion or duplication. The modified biopsy protocol was associated with fewer segmental abnormalities (20% versus 33.3%; odds ratio: 0.5, 95% confidence interval: 0.26 to 0.97) and fewer segmental deletion mosaics (10.5% versus 23.7%; odds ratio: 0.38, 95% confidence interval: 0.17 to 0.85) compared with the second biopsy.

Conclusions: A clinical mosaic embryo with simple segmental deletion was extremely low predictive of the embryo. Removal of cell debris from biopsy samples may reduce the incidence of segmental deletion mosaics.

Background: A link between idiopathic male infertility and viral infections exhibiting seminal carriage has emerged recently. In this respect, human papillomavirus (HPV) appears to be the most prevalent sexually transmitted agent worldwide. The viruses present in the genital environment comprise the genital virome. HPV infection reportedly disrupts homeostasis of the virome in women but this topic has not previously been studied in men.

Methods: This was a retrospective study of males attending the fertility clinic at Amiens University Medical Center (Amiens, France). Men with a multiple-type HPV infection in the sperm (n = 15) were considered to be cases, and men with no detectable HPV in the sperm were considered to be controls (n = 13). The molecular virome in cases and controls was described via metagenomic next-generation sequencing. The cases and controls were compared with regard to genomic, clinical and sperm-related characteristics.

Results: The seminal virome analysis revealed the predominance of Papillomaviridae in cases (63.4%). Other virus families found in both groups (albeit with lower proportions of reads in cases than in controls) were Herpesviridae (6.9% vs. 40.5%, respectively), Polyomaviridae (11.3% vs. 17.8%, respectively), and other viral sequences (18.4% vs. 40%, respectively). There was no difference in viral diversity between the two groups (p = 0.0692). Viral diversity was correlated with the semen sample volume, progressive sperm motility, total motility, and sperm vitality in cases but not in controls. Univariate and multivariate comparative analyses did not reveal significant differences in sperm parameters between cases and controls.

Conclusions: The male seminal virome mainly comprises viruses from the Papillomaviridae, Herpesviridae and Polyomaviridae families. The correlation between viral diversity and sperm parameters in HPV-positive patients suggests that HPV-specific interactions within the seminal virome are responsible for variations in sperm parameters. Hence, alterations in the seminal virome (due mostly to HPV infection) might impact sperm parameters and thus male fertility.

Background: The application of Artificial Intelligence (AI) to sperm selection during Intracytoplasmic Sperm Injection (ICSI) procedures represents one of the most innovative advances in assisted reproductive technology (ART). Traditional sperm selection relies heavily on the subjective assessment of embryologists, which can lead to variability in outcomes. This study aimed to evaluate the performance of an AI-based software, Sperm ID (SiD™) v.1.0, for sperm selection during ICSI and to compare its outcomes with those obtained by experienced embryologists. Additionally, the study assessed the potential impact of sperm and oocyte quality, particularly in autologous versus donor oocyte cycles.

Methods: A single-center, blind, observational study was conducted involving 102 infertile couples-60 undergoing treatment with autologous oocytes and 42 using oocytes from a donation program. Semen samples were analyzed in real time with SiD™ v.1.0, a software that quantifies progressive motility parameters and assigns each sperm a categorical score ('Best,' 'Good,' 'Medium,' or 'low'). Spermatozoa and oocytes were individually tracked from injection to embryo development. Oocyte quality was retrospectively analyzed using another AI tool, Magenta IVF R3.0. The performance of the Artificial Intelligence Sperm Selection (AISS) system was compared with that of senior embryologists (> 300 ICSI cycles/year). Statistical analysis included descriptive statistics and inferential tests to compare fertilization and embryo development rates across sperm categories and between autologous and donor cycles.

Results: Biological outcomes-such as fertilization and blastocyst development-were generally similar across all sperm quality categories. However, in cycles with autologous oocytes, the use of top-quality sperm ('Best' category) was associated with a significantly higher blastocyst formation rate. In contrast, no significant differences were observed in donor oocyte cycles, regardless of sperm quality. The AISS system demonstrated comparable performance to that of senior embryologists, with similar fertilization and embryo development rates.

Conclusions: The study highlights the promising role of AI-based tools in standardizing and enhancing sperm selection during ICSI. While AI-driven sperm selection showed limited impact in donor cycles, it may offer a distinct advantage in cases involving compromised oocyte quality. Furthermore, AISS may improve laboratory efficiency and support junior embryologists by reducing selection time and increasing procedural consistency.

Background: Pregnancy involves a fine-tuned hormonal interplay between the fetus, placenta, and mother, which shapes long-term developmental outcomes. Endometriosis has been hypothesized to originate in utero due to altered fetal exposure to sex steroids. This study investigates differences in umbilical cord estradiol and androgen levels in female fetuses born to women with and without endometriosis, exploring a potential role of altered in utero hormone exposure in the intergenerational transmission of endometriosis risk.

Methods: This is a case-control study nested within a cohort of women delivering singleton females at our institution between June 2022 and June 2023. Cases were women with endometriosis (diagnosed via imaging or surgery before pregnancy) and controls were women without endometriosis. Analyses were performed before and after propensity-score matching (PSM) at a 1:3 ratio to control for maternal age, gestational age, and delivery mode. Umbilical cord blood was collected at delivery, and hormonal levels of corticosteroids, progestins, androgens, and estradiol (E2) were measured using liquid chromatography-tandem mass spectrometry. Estradiol-to-androgens ratios were calculated, with 95% confidence intervals (CIs) determined using the bootstrapping method.

Results: The total cohort included 160 women, 17 (10.6%) of whom had endometriosis. After 1:3 matching, 51 controls without endometriosis were included. Women with endometriosis had higher E2 levels compared to controls, both before PSM (6.8 [4.3-9.1] mcg/L vs. 3.6 [1.4-8.6] mcg/L, p = 0.03) and after PSM (2.4 [1.1-6.6] mcg/L, p = 0.002). Estradiol-to-androgens ratios indicated a higher-estrogen and lower-androgens hormonal status in endometriosis, with higher E2-to-testosterone (p < 0.001), E2-to-androstenedione (p = 0.001), E2-to-dehydroepiandrosterone (DHEA) (p < 0.001), and E2-to-DHEA sulfate (DHEAS) ratios (p < 0.001) compared to controls. After PSM, the E2-to-testosterone, E2-to-androstenedione, E2-to-DHEA, and E2-to-DHEAS ratios were 4.38 (95% CI: 2.28-6.49), 3.28 (95% CI: 1.29-5.28), 2.52 (95% CI: 1.32-3.72), and 4.57 (95% CI: 1.86-7.27) times higher, respectively.

Conclusions: This is the first study showing that female newborns of women with endometriosis are exposed to higher in utero estradiol compared to controls. This high estrogen low androgens environment may influence fetal programming of reproductive traits and might drive the in utero susceptibility to endometriosis.