Mendelian randomization reveals the impact of diet on infertility in men and women.

Background: Although studies on the effects of diet on fertility has progressed, some cumulative evidence has piled against popular hypotheses. The aim of our study was to investigate the effects of 31 diets including 23 individual dietary intakes and 8 dietary habits on infertility in men and women. Methods: The datas of diets and infertility were collected from genome-wide association studies (GWAS). Mendelian randomization (MR) methods were used to analyze causal relationships. Multivariate MR (MVMR) adjusted for the effects of other exposures on causality. And MR-Egger, Cochran's Q, radial MR, and MR-PRESSO tests were employed to assess heterogeneity and horizontal pleiotropy. Results: Our study found that coffee intake (OR, 3.6967; 95% CI, 1.0348 - 13.2065; P = 0.0442) and cooked vegetable intakes (OR, 54.7865; 95% CI, 2.9011 - 1030.5500; P = 0.0076) increased the risk of male infertility. For women, beer was a risk factor for infertility (OR, 4.0932; 95% CI, 1.8728 - 8.9461; P = 0.0004); but processed meat was negatively associated with infertility (OR, 0.5148; 95% CI, 0.2730 - 0.9705; P = 0.0401). MVMR demonstrated selenium as a protective factor against female infertility (OR, 7.4474e-12; 95% CI, 5.4780e-22 - 1.0125e-01; P = 0.0314). Conclusion: We found the causal relationships between four diets and infertility. We look forward to more high-quality epidemiologic studies to prove our conclusions.

Reactive oxygen species and their role in the andrological factor of couple fertility.

Reactive oxygen species play a significant role in male fertility and infertility. They are essential for physiological processes, but when their concentration becomes excessive, they can be a cause of various sperm pathologies. Seminal leukocytes and pathologically abnormal sperm are the primary sources of oxygen radicals in ejaculate. They negatively affect sperm quality, including DNA fragmentation and sperm motility impairment. Addressing increased concentrations of reactive oxygen species involves various appropriate lifestyle modifications and measures, including the use of antioxidants, treatment of urogenital infections, management of varicocele, weight reduction, and others. In many cases, these interventions can lead to adjustments in the condition and improvement in sperm quality. Such improvements can subsequently lead to enhanced outcomes in assisted reproduction or even an increased likelihood of natural conception. In some instances, the need for donor sperm may be eliminated. However, a key factor is adhering to a sufficiently prolonged treatment, which requires patience on the part of both, the physician and the patient.

[Clinical guidelines for male infertility: controversial issues and the need to reach interdisciplinary consensus].

A review of controversial issues about the terminology on male infertility and reproductive function, which is currently used, as well as proposals for updating clinical guidelines for the diagnosis and treatment of male infertility and men in infertile couples are presented in the article. An algorithm is described, the elements of which ensure referral of patients based on the possibility and timing of restoration of reproductive function, taking into account the reproductive health of a woman, as well as increasing the likelihood of successful treatment aimed at the birth of a healthy child.

Radiation and male reproductive system: Damage and protection.

Male fertility has been declining in recent decades, and a growing body of research points to environmental and lifestyle factors as the cause. The widespread use of radiation technology may result in more people affected by male infertility, as it is well established that radiation can cause reproductive impairment in men. This article provides a review of radiation-induced damage to male reproduction, and the effects of damage mechanisms and pharmacotherapy. It is hoped that this review will contribute to the understanding of the effects of radiation on male reproduction, and provide information for research into drugs that can protect the reproductive health of males.

The Clinical Investigation on Varicocele and Sperm Quality in the Tibet an Plateau of China: A Prospectively Planned Retrospective Cohort Study.

Varicoceles are a common cause of male infertility, affecting up to 35% of men undergoing fertility evaluations. This study aims to investigate the potential influence of altitude and residence time on the occurrence of varicoceles, as well as on sperm quality and sterility in plateau areas. A total of 168 patients with varicocele were enrolled in the study, and the study population was divided into groups based on their direct exposure to different high altitudes due to their living locations. The internal diameter in Quiet breath (Dr), internal diameter in Valsalva maneuver (Dv), reflux peak value, and reflux time are gradually increased accompanied with altitude elevation and residence time extension. The number of cases above 4,500 m also increased with the severity of varicocele, and the altitude of clinical types was higher than that of subclinical types of varicocele. Especially above 4,500 m, the Dv, Dr, reflux peak value, and reflux time all increased with the severity of varicocele. The severity of varicocele was positively correlated with the residence time in plateau area. Patients with residence time of more than 1 year had higher values of Dr, Dv, differentiation time, reflux peak value, and reflux time than those with residence time of less than 1 year. Compared to 3,650 m, patients with varicocele in 4,500 m also have worse semen quality. Both altitude and residence time are strongly positively related to the severity and incidence rate of varicocele in plateau areas.

Dual-Activated H2O2-Responsive AIE Probes for Oocyte Quality Assessment.

Nonobstructive azoospermia (NOA) is an important cause of infertility, and intracytoplasmic sperm injection (ICSI) is the mainstay of treatment for these patients. In cases where a sufficient number of sperm (usually 1-2) is not available, the selection of oocytes for ICSI is a difficult problem that must be solved. Here, we constructed a dual-activated oxidative stress-responsive AIE probe, b-PyTPA. The strong donor-acceptor configuration of b-PyTPA leads to twisted intramolecular charge transfer (TICT) effect that quenches the fluorescence of the probe, however, H2O2 would specifically remove the boronatebenzyl unit and release a much weaker acceptor, which inhibits TICT and restores the fluorescence. In addition, the presence of a pyridine salt makes b-PyTPA more hydrophilic, whereas removal of the pyridine salt increases the hydrophobicity of PyTPA, which triggers aggregation and further enhances fluorescence. Thus, the higher the intracellular level of oxidative stress, the stronger the fluorescence. In vitro, this dual-activated fluorescent probe is capable of accurately detecting senescent cells (high oxidative stress). More importantly, b-PyTPA was able to characterize senescent oocytes, as assessed by the level of oxidative stress. It is also possible to identify high quality oocytes from those obtained for subsequent ICSI. In conclusion, this dual-activated oxidative stress-assessment probe enables the quality assessment of oocytes and has potential application in ICSI.

Examination of ejaculate fructose levels on male infertility patients at various times and centrifugation using semiautomatic method.

OBJECTIVE: Various factors, such as obstructive azoospermia, cause infertility in men. Biochemical examination of ejaculate, especially measurement of fructose, can be an additional investigation that can be used for this diagnosis in reproductive health. Examination of fructose is carried out after routine ejaculate analysis, resulting in prolonging the examination time so that it will affect the measurement of fructose level in the ejaculate and the accuracy of the diagnosis. This study aims to determine the best timing and procedure for measurement of fructose using a semiautomatic method. METHODS: This research is an analytic observational study conducted at Dr. Soetomo General Hospital, Surabaya. A total of 13 ejaculate samples from infertile male patients who met the inclusion criteria were evaluated. Each ejaculate was divided into eight aliquots that were examined for fructose using a semiautomated method after different intervals of time and centrifugation modalities. RESULTS: This study showed a significant difference in fructose levels when aliquots were centrifuged and examined immediately or after different interval of time (p=0.036). In addition, aliquots left standing for more than 60 minutes (p=0.012) and 120 minutes (p<0.001) before centrifugation, showed significantly lower levels compared to aliquots that were centrifuged and then immediately examined. CONCLUSIONS: We suggest that measuring fructose immediately after centrifugation is more reliable than measuring fructose left standing before or after centrifugation. Leaving the ejaculate standing will reduce the fructose level so that it does not resemble its real level.

A multi-modal approach to investigate Desmodium gangeticum's influence on stress-induced male infertility: In vivo, in vitro, and in silico assessments.

Physical and psychological stress has an inverse relation with male libido and sperm quality. The present study investigates the potential fertility-enhancing properties of Desmodium gangeticum (DG) root extracts in male Wister rats subjected to immobilization-induced stress (SIMB). DG roots were extracted using n-hexane (HEDG), chloroform (CEDG), and water (AEDG). In the pilot study, aphrodisiac protentional was investigated at two doses (125 and 250 mg kg-1) of each extract. In the main study, the HEDG and AEDG at 125 and 250 mg kg-1 were challenged for the stress by immobilization (SIMB), for 6 h daily over 28 days. Parameters assessed included aphrodisiac effects, gonadosomatic index (GSI), semen quality, sperm quantity, fructose content, serum hormonal levels, testicular oxidative stress, and testicular histopathology. Additional in silico studies, including the lipid solubility index, molecular docking, molecular dynamics, and SymMap studies were conducted for validation. HEDG demonstrated significant aphrodisiac activity, improved - GSI, sperm quality and quantity, and fructose content, serum testosterone levels, histological changes induced by SIMB in the testes. Swiss ADME studies indicated Gangetin (a pterocarpan) had a high brain permeation index (4.81), a superior docking score (-8.22), and higher glide energy (-42.60), compared with tadalafil (-7.17). The 'Lig fit Prot' plot in molecular dynamics simulations revealed a strong alignment between Gangetin and phosphodiesterase type 5 (PDE5). HEDG exerts aphrodisiac effects by increasing blood testosterone levels and affecting PDE5 activity. The protective effects on spermatozoa-related parameters and testicular histological changes are attributed to the antioxidant and anti-inflammatory properties, of pterocarpan (gangetin).

Causal relationship between genetically predicted type 2 diabetes mellitus and male infertility.

Background: Diabetes mellitus (DM) stands as the most prevalent endocrine abnormality affecting the physiological systems and organs and impairing the male reproductive functions. Type 2 Diabetes Mellitus (T2DM), accounting for about 90-95% of DM, is closely associated with male infertility. However, the magnitude of the causal relationships between T2DM and male infertility remains unclear. The current investigation was to explore the causal relationship between T2DM and male infertility utilizing the Mendelian Randomization (MR) analysis. Methods: A two-sample MR (2SMR) analysis was conducted to investigate the causal relationship between T2DM and male infertility in the European population from the genome-wide association study (GWAS) summary data that was publicly accessible. GWAS for T2DM and male infertility were extracted from the IEU Open GWAS Project database, with the resulting data encompassing 680 cases and 72,799 controls as the outcome data. Five MR methods were employed for the 2SMR analyses, namely the MR-Egger, weighted median estimation (WME), weighted mode (WM), inverse-variance weighted (IVW), and simple mode. The primary analytical technique utilized in this study was the IVW method, and a multivariate MR analysis was executed to examine the potential mediating influences of T2DM on male infertility. Results: Following were the odds ratios (ORs) and associated 95% CIs derived from IVW (fixed effects), MR-Egger, WM, WME, and simple mode approaches: 0.824 (95% CI 0.703-0.966), 0.726 (95% CI 0.527-1.001), 0.827 (95% CI 0.596-1.150), 0.841 (95% CI 0.654-1.082), and 0.875 (95% CI 0.544-1.405), respectively. The outcomes of the heterogeneity tests were P=0.378 and P=0.384, respectively, implying no heterogeneity. Egger-intercept outcomes were P=0.374, highlighting the absence of pleiotropy. The stability of the results was affirmed through the leave-one-out analysis. Notably, all F-values surpassed 10, indicating the absence of weak bias attributed to instrument variables(IVs). Conclusions: This research furnishes evidence supporting a causal association between T2DM and male infertility. These insights offer a foundation for future investigations aiming to establish the association between genetically predicted T2DM and male infertility. These outcomes suggest the significance of active monitoring and proactive measures for preventing infertility in male individuals with T2DM. Furthermore, careful consideration is required for individuals of reproductive age to prevent and treat T2DM.

Effects of radiofrequency electromagnetic field (RF-EMF) exposure on male fertility: A systematic review of experimental studies on non-human mammals and human sperm in vitro.

BACKGROUND: The World Health Organization is coordinating an international project aimed at systematically reviewing the evidence regarding the association between radiofrequency electromagnetic field (RF-EMF) exposure and adverse health effects. Reproductive health outcomes have been identified among the priority topics to be addressed. OBJECTIVES: To evaluate the effect of RF-EMF exposure on male fertility of experimental mammals and on human sperm exposed in vitro. METHODS: Three electronic databases (PubMed, Scopus and EMF Portal) were last searched on September 17, 2022. Two independent reviewers screened the studies, which were considered eligible if met the following criteria: 1) Peer-reviewed publications of sham controlled experimental studies, 2) Non-human male mammals exposed at any stage of development or human sperm exposed in vitro, 3) RF-EMF exposure within the frequency range of 100 kHz-300 GHz, including electromagnetic pulses (EMP), 4) one of the following indicators of reproductive system impairment:Two reviewers extracted study characteristics and outcome data. We assessed risk of bias (RoB) using the Office of Health Assessment and Translation (OHAT) guidelines. We categorized studies into 3 levels of overall RoB: low, some or high concern. We pooled study results in a random effects meta-analysis comparing average exposure to no-exposure and in a dose-response meta-analysis using all exposure doses. For experimental animal studies, we conducted subgroup analyses for species, Specific Absorption Rate (SAR) and temperature increase. We grouped studies on human sperm exposed in vitro by the fertility status of sample donors and SAR. We assessed the certainty of the evidence using the GRADE approach after excluding studies that were rated as "high concern" for RoB. RESULTS: One-hundred and seventeen papers on animal studies and 10 papers on human sperm exposed in vitro were included in this review. Only few studies were rated as "low concern" because most studies were at RoB for exposure and/or outcome assessment. Subgrouping the experimental animal studies by species, SAR, and temperature increase partly accounted for the heterogeneity of individual studies in about one third of the meta-analyses. In no case was it possible to conduct a subgroup analysis of the few human sperm in vitro studies because there were always 1 or more groups including less than 3 studies. Among all the considered endpoints, the meta-analyses of animal studies provided evidence of adverse effects of RF-EMF exposure in all cases but the rate of infertile males and the size of the sired litters. The assessment of certainty according to the GRADE methodology assigned a moderate certainty to the reduction of pregnancy rate and to the evidence of no-effect on litter size, a low certainty to the reduction of sperm count, and a very low certainty to all the other meta-analysis results. Studies on human sperm exposed in vitro indicated a small detrimental effect of RF-EMF exposure on vitality and no-effect on DNA/chromatin alterations. According to GRADE, a very low certainty was attributed to these results. The few studies that used EMP exposure did not show effects on the outcomes. A low to very low certainty was attributed to these results. DISCUSSION: Many of the studies examined suffered of severe limitations that led to the attribution of uncertainty to the results of the meta-analyses and did not allow to draw firm conclusions on most of the endpoints. Nevertheless, the associations between RF-EMF exposure and decrease of pregnancy rate and sperm count, to which moderate and low certainty were attributed, are not negligible, also in view of the indications that in Western countries human male fertility potential seems to be progressively declining. It was beyond the scope of our systematic review to determine the shape of the dose-response relationship or to identify a minimum effective exposure level. The subgroup and the dose-response fitting analyses did not show a consistent relationship between the exposure levels and the observed effects. Notably, most studies evaluated RF-EMF exposure levels that were higher than the levels to which human populations are typically exposed, and the limits set in international guidelines. For these reasons we cannot provide suggestions to confirm or reconsider current human exposure limits. Considering the outcomes of this systematic review and taking into account the limitations found in several of the studies, we suggest that further investigations with better characterization of exposure and dosimetry including several exposure levels and blinded outcome assessment were conducted. PROTOCOL REGISTRATION: Protocols for the systematic reviews of animal studies and of human sperm in vitro studies were published in Pacchierotti et al., 2021. The former was also registered in PROSPERO (CRD42021227729 https://www.crd.york.ac.uk/prospero/display_record.php?RecordID = 227729) and the latter in Open Science Framework (OSF Registration DOI https://doi.org/10.17605/OSF.IO/7MUS3).

Decreased AdipoR1 signaling and its implications for obesity-induced male infertility.

Obesity is among the risk factors for male infertility. Although several mechanisms underlying obesity-induced male subfertility have been reported, the entire mechanism of obesity-induced male infertility still remains unclear. Here, we show that sperm count, sperm motility and sperm fertilizing ability were decreased in male mice fed a high-fat diet and that the expression of the AdipoR1 gene and protein was decreased, and the expression of pro-apoptotic genes and protein increased, in the testis from mice fed a high-fat diet. Moreover, we demonstrate that testes weight, sperm count, sperm motility and sperm fertilizing ability were significantly decreased in AdipoR1 knockout mice compared to those in wild-type mice; furthermore, the phosphorylation of AMPK was decreased, and the expression of pro-apoptotic genes and proteins, caspase-6 activity and pathologically apoptotic seminiferous tubules were increased, in the testis from AdipoR1 knockout mice. Furthermore, study findings show that orally administrated AdipoRon decreased caspase-6 activity and apoptotic seminiferous tubules in the testis, thus ameliorating sperm motility in male mice fed a high-fat diet. This was the first study to demonstrate that decreased AdipoR1/AMPK signaling led to increased caspase-6 activity/increased apoptosis in the testis thus likely accounting for male infertility.

Microsurgical varicocelectomy efficacy in treatment of men with primary and secondary infertility (retrospective study).

INTRODUCTION AND OBJECTIVES: Varicocele is the most common treatable cause of male infertility. The study aimed to compare varicocelectomy efficacy in men with primary (PI) and secondary infertility (SI). PATIENTS AND METHODS: Medical records of 100 men suffering from PI and SI and having varicocelectomy at the Republican Specialized Scientific-Practical Medical Center of Urology were retrospectively selected and analyzed. Patients were divided into 2 groups. Group I included 58 men with PI and Group II 42 men with SI. Preoperative clinical characteristics and semen parameters before and after varicocelectomy were analyzed and compared between groups. RESULTS: Analysis revealed that the mean age of patients of group I was significantly lower (p<0.001) and the duration of infertility was accurately shorter (p<0.01) than those of group II. Main semen parameters increased significantly in group I (e.g., sperm concentration increased by 50%, from 62.2 ± 8.7 to 93.5 ± 10.0 M/ml, and total motile sperm count increased by 113%, from 76.7±17.1 to 163.4±27.8 M p<0.05), while in group II only rate of progressive motile sperm increased significantly (by 107%, from 13.5± .6 to 28.0±5.2% p<0.05). We identified a significant difference in varicocelectomy efficacy between group I and group II in change of total motile sperm count (by 113% vs 74% respectively, p<0.01). We also revealed a discrepancy between groups in correlation ratio (r) between initial and post-surgical percent of progressive motile sperm. CONCLUSIONS: Patients with SI were older and had longer infertility period. Varicocelectomy resulted in significant semen parameters improvement in patients with PI. In patients with SI, only a percent of progressively motile sperm improved significantly. It indicates that advanced male age and long infertility duration may have a negative impact on varicocelectomy success.

[First-line management of infertile couple. Guidelines for clinical practice of the French College of Obstetricians and Gynecologists 2022]. / Prise en charge de première intention du couple infertile : mise à jour des RPC 2010 du CNGOF.

OBJECTIVE: To update the 2010 CNGOF clinical practice guidelines for the first-line management of infertile couples. MATERIALS AND METHODS: Five major themes (first-line assessment of the infertile woman, first-line assessment of the infertile man, prevention of exposure to environmental factors, initial management using ovulation induction regimens, first-line reproductive surgery) were identified, enabling 28 questions to be formulated using the Patients, Intervention, Comparison, Outcome (PICO) format. Each question was addressed by a working group that had carried out a systematic review of the literature since 2010, and followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) methodology to assess the quality of the scientific data on which the recommendations were based. These recommendations were then validated during a national review by 40 national experts. RESULTS: The fertility work-up is recommended to be prescribed according to the woman's age: after one year of infertility before the age of 35 and after 6months after the age of 35. A couple's initial infertility work-up includes a single 3D ultrasound scan with antral follicle count, assessment of tubal permeability by hysterography or HyFOSy, anti-Mullerian hormone assay prior to assisted reproduction, and vaginal swabbing for vaginosis. If the 3D ultrasound is normal, hysterosonography and diagnostic hysteroscopy are not recommended as first-line procedures. Chlamydia trachomatis serology does not have the necessary performance to predict tubal patency. Post-coital testing is no longer recommended. In men, spermogram, spermocytogram and spermoculture are recommended as first-line tests. If the spermogram is normal, it is not recommended to check the spermogram. If the spermogram is abnormal, an examination by an andrologist, an ultrasound scan of the testicles and hormonal test are recommended. Based on the data in the literature, we are unable to recommend a BMI threshold for women that would contraindicate medical management of infertility. A well-balanced Mediterranean-style diet, physical activity and the cessation of smoking and cannabis are recommended for infertile couples. For fertility concern, it is recommended to limit alcohol consumption to less than 5 glasses a week. If the infertility work-up reveals no abnormalities, ovulation induction is not recommended for normo-ovulatory women. If intrauterine insemination is indicated based on an abnormal infertility work-up, gonadotropin stimulation and ovulation monitoring are recommended to avoid multiple pregnancies. If the infertility work-up reveals no abnormality, laparoscopy is probably recommended before the age of 30 to increase natural pregnancy rates. In the case of hydrosalpinx, surgical management is recommended prior to ART, with either salpingotomy or salpingectomy depending on the tubal score. It is recommended to operate on polyps>10mm, myomas 0, 1, 2 and synechiae prior to ART. The data in the literature do not allow us to systematically recommend asymptomatic uterine septa and isthmoceles as first-line surgery. CONCLUSION: Based on strong agreement between experts, we have been able to formulate updated recommendations in 28 areas concerning the initial management of infertile couples.

Identification of two hidden clinical subgroups among men with idiopathic cryptozoospermia.

STUDY QUESTION: Are there subgroups among patients with cryptozoospermia pointing to distinct etiologies? SUMMARY ANSWER: We reveal two distinct subgroups of cryptozoospermic (Crypto) patients based on testicular tissue composition, testicular volume, and FSH levels. WHAT IS KNOWN ALREADY: Cryptozoospermic patients present with a sperm concentration below 0.1 million/ml. While the etiology of the severely impaired spermatogenesis remains largely unknown, alterations of the spermatogonial compartment have been reported including a reduction of the reserve stem cells in these patients. STUDY DESIGN, SIZE, DURATION: To assess whether there are distinct subgroups among cryptozoospermic patients, we applied the statistical method of cluster analysis. For this, we retrospectively selected 132 cryptozoospermic patients from a clinical database who underwent a testicular biopsy in the frame of fertility treatment at a university hospital. As controls (Control), we selected 160 patients with obstructive azoospermia and full spermatogenesis. All 292 patients underwent routine evaluation for endocrine, semen, and histological parameters (i.e. the percentage of tubules with elongated spermatids). Moreover, outcome of medically assisted reproduction (MAR) was assessed for cryptozoospermic (n = 73) and Control patients (n = 87), respectively. For in-depth immunohistochemical and histomorphometrical analyses, representative tissue samples from cryptozoospermic (n = 27) and Control patients (n = 12) were selected based on cluster analysis results and histological parameters. PARTICIPANTS/MATERIALS, SETTING, METHODS: This study included two parts: firstly using clinical parameters of the entire cohort of 292 patients, we performed principal component analysis (PCA) followed by hierarchical clustering on principal components (i.e. considering hormonal values, ejaculate parameters, and histological information). Secondly, for histological analyses seminiferous tubules were categorized according to the most advanced germ cell type present in sections stained with Periodic acid Schif. On the selected cohort of 39 patients (12 Control, 27 cryptozoospermic), we performed immunohistochemistry for spermatogonial markers melanoma-associated antigen 4 (MAGEA4) and piwi like RNA-mediated gene silencing 4 (PIWIL4) followed by quantitative analyses. Moreover, the morphologically defined Adark spermatogonia, which are considered to be the reserve stem cells, were quantified. MAIN RESULTS AND THE ROLE OF CHANCE: The PCA and hierarchical clustering revealed three different clusters, one of them containing all Control samples. The main factors driving the sorting of patients to the clusters were the percentage of tubules with elongated spermatids (Cluster 1, all Control patients and two cryptozoospermic patients), the percentage of tubules with spermatocytes (Cluster 2, cryptozoospermic patients), and tubules showing a Sertoli cells only phenotype (Cluster 3, cryptozoospermic patients). Importantly, the percentage of tubules containing elongated spermatids was comparable between Clusters 2 and 3. Additional differences were higher FSH levels (P < 0.001) and lower testicular volumes (P < 0.001) in Cluster 3 compared to Cluster 2. In the spermatogonial compartment of both cryptozoospermic Clusters, we found lower numbers of MAGEA4+ and Adark spermatogonia but higher proportions of PIWIL4+ spermatogonia, which were significantly correlated with a lower percentage of tubules containing elongated spermatids. In line with this common alteration, the outcome of MAR was comparable between Controls as well as both cryptozoospermic Clusters. LIMITATIONS, REASONS FOR CAUTION: While we have uncovered the existence of subgroups within the cohort of cryptozoospermic patients, comprehensive genetic analyses remain to be performed to unravel potentially distinct etiologies. WIDER IMPLICATIONS OF THE FINDINGS: The novel insight that cryptozoospermic patients can be divided into two subgroups will facilitate the strategic search for underlying genetic etiologies. Moreover, the shared alterations of the spermatogonial stem cell compartment between the two cryptozoospermic subgroups could represent a general response mechanism to the reduced output of sperm, which may be associated with a progressive phenotype. This study therefore offers novel approaches towards the understanding of the etiology underlying the reduced sperm formation in cryptozoospermic patients. STUDY FUNDING/COMPETING INTEREST(S): German research foundation CRU 326 (grants to: SDP, NN). Moreover, we thank the Faculty of Medicine of the University of Münster for the financial support of Lena Charlotte Schülke through the MedK-program. We acknowledge support from the Open Access Publication Fund of the University of Münster. The authors have no potential conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.

Relationship between semen parameters, serum InhB, and INSL-3 levels, and the degree of varicocele.

BACKGROUND: Varicocele is an abnormal expansion of the pampininias venous plexus in the scrotum, resulting in impaired sperm production and reduced sperm quality. The exact pathophysiological mechanism leading to varicocele-related infertility has not been fully elucidated. Although treatable, varicocele may lead to male infertility. OBJECTIVE: To investigate the relationship between semen parameters, serum InhB and INSL-3 levels, and the degree of varicocele in male patients. METHODS: Serum InhB and INSL-3 were detected. To evaluate the relationship between semen parameters and serum InhB and INSL-3 levels. To evaluate the value of semen parameters and serum InhB and INSL-3 levels in distinguishing disease severity in patients with varicocele. RESULTS: Serum INSL-3 in patients with varicocele decreased with the severity of the disease. Serum INSL-3 was positively correlated with total sperm count and frequency of normal sperm morphology. There was a weak correlation between serum InhB and semen volume, concentration, and total sperm. Patients with different disease severity were similar within the groups, with partial overlap or similarity between varicocele Grade I and Grade II, and significant differences between Grade III and Grade I and II. Semen volume, concentration, total sperm, normal sperm morphology, and serum InhB and INSL-3 levels could distinguish the degree of varicocele. CONCLUSION: Semen parameters and the combination of serum InhB and INSL-3 levels in patients with varicocele are closely related to the severity of the disease. Serum INSL-3 is expected to be a potential biomarker for early clinical intervention.

Thyroid impairment and male fertility: a narrative review of literature.

PURPOSE: To evaluate the effect of thyroid function on male fertility, focusing on hypo- and hyperthyroidism. METHODS: A PubMed/MEDLINE, Web of Science, and Scopus research was performed. Original studies in English published online up to 31 May 2023 were selected and reviewed. The final reference list was defined based on the relevance of each paper to the scope of this review. RESULTS: The available data in animals (31 studies) and human (26 studies) showed conflicting results. However, thyroid dysfunction altered erection and ejaculation both in animal models than in men. CONCLUSION: Both hypothyroidism and hyperthyroidism seem to cause ejaculation and erectile dysfunction. Hence, Guidelines recommend against the systematic screening for thyroid disorders in the men in sub-fertile couples, but only in men with ejaculation and erectile dysfunction and/or altered semen parameters.