Male sexual dysfunctions (SDs) like erectile dysfunction (ED), premature ejaculation (PE), and Peyronie's disease (PD) are highly prevalent conditions affecting the quality of life of men and their partners. Botulinum toxin (BTX) is emerging as a promising injectable therapy to treat male SDs. To systematically review the current evidence on the use of BTX in the treatment of male SDs. PubMed, Cochrane, and EMBASE databases were queried for all published studies indexed up to October 2024 using predefined keywords. Of 108 identified articles, 9 (6 on ED, 2 on PE, and only 1 on PD) met our inclusion criteria. In ED, BTX improved International Index of Erectile Function-Erectile Function domain (IIEF-EF) scores in 41%-57.4% of patients, with benefits lasting up to 6 months. In PE, BTX increased ejaculation latency and subjective satisfaction at 1-3 months, but the effects diminished by 6 months. In PD, a single study showed a significant reduction in penile curvature (-7.9°), plaque thickness, and penile pain. Adverse effects were mild and local, reported in less than 10% of cases. BTX injections demonstrate promising improvements in erectile function, ejaculation latency, and penile curvature with a favourable safety profile. However, current evidence is limited by small, heterogeneous studies and the absence of large randomized controlled trials. Further research is needed to establish optimal dosing, timing, and patient selection.

Emerging evidence suggests that the seminal microbiota may play a role in male reproductive health, yet its relationship with sperm parameters remains poorly understood. This study explores the link between seminal microbiota composition and sperm parameters to understand their impact on the male reproductive function. This prospective cross-sectional study included 100 eugonadal adult men evaluated at a university-affiliated Endocrinology and Andrology Division. Seminal concentrations of lactobacilli, anerobic, and facultative bacteria, along with serum luteinizing hormone, follicle-stimulating hormone, and testosterone, were assessed alongside conventional sperm parameters. Conventional sperm parameters and seminal leukocyte counts were analyzed. Regression models were used to explore associations, and predictive thresholds for sperm concentration >16 mil/mL and sperm progressive motility >30% were determined. Seminal lactobacillus concentration positively correlated with sperm concentration (r = 0.42, p < 0.001). Seminal leukocyte concentration and percentage of immature germ cells (spermatids) identified at semen analysis showed negative correlations (r = -0.35, p = 0.002; r = -0.37, p < 0.001, respectively). Anerobic and facultative bacteria negatively correlated with sperm progressive motility (r = -0.77, p < 0.001) and positively correlated with percentage of spermatids (r = 0.72, p < 0.001). The lactobacilli-to-total bacteria ratio negatively correlated with leukocyte concentration (r = -0.96, p < 0.001) and percentage of spermatids (r = -0.89, p <0.001), and positively with sperm progressive motility (r = 0.95, p < 0.001). All of these correlations remained significant after adjustments. Concentrations of lactobacilli, anerobic/facultative bacteria, and the lactobacilli/total bacteria ratio were strong predictors of sperm concentration and motility, demonstrating high sensitivity and specificity. Our findings suggest that the composition of the seminal microbiota, particularly the relative abundance of lactobacilli versus anerobic/facultative bacteria, may influence key sperm parameters such as concentration and motility. This highlights the potential clinical relevance of microbiota profiling in the male fertility assessment. A higher abundance of seminal lactobacilli is associated with more favorable sperm parameters, while anerobic and facultative bacteria are linked to poorer outcomes. Microbiota analysis may offer additional insights into male infertility diagnostics, though further studies are needed to confirm causality.

ABSTRACTBackgroundEpidemiological studies have reported an association between advanced paternal age at conception and an increased risk of neurodevelopmental disorders in offspring, such as autism spectrum disorder. Evidence suggests that DNA methylation alterations in spermatozoa of older men may be transmitted to the feto‐placental unit and associated with offspring brain development and behavioral differences later in childhood.ObjectiveWe aimed to assess the association of advanced paternal age with DNA methylation alterations in the human placenta and compare the results to previous findings in spermatozoa.MethodsFor this study, 64 placenta samples from the Design, Develop, and Discover (3D) prospective birth cohort study were categorized based on paternal age at conception. DNA methylation of the placenta was interrogated using the Illumina 850K array. There were no differentially methylated sites found to be statistically significant after correction for multiple comparisons, therefore sites with significant nominal p values < 0.05 were assessed and used to define differentially methylated regions (DMRs) associated with genes.ResultsAdvanced paternal age was associated with DNA methylation alterations in the placenta at up to 688 genes, with a predominance of hypomethylation (65%), including at eight imprinted loci. About 7% of genes with age‐associated DNA methylation changes in placenta overlapped with genes previously reported to show altered DNA methylation in spermatozoa of older men; seven genes common to placenta and spermatozoa had previously been identified in association with susceptibility to autism spectrum disorder. Among loci most affected, we found evidence of sex‐specific hypermethylation at genes linked to neurodevelopment (GRM7, EBF3, FOXG1).ConclusionOur findings suggest that advanced paternal age at conception correlates with altered DNA methylation at a small number of loci in the human placenta, notably affecting genes involved in neurodevelopment. This study highlights the use of the placenta DNA methylome as a surrogate marker for the potential impact of advanced paternal age on the child.

In 2022, a repeatable protocol for in vitro fertilization (IVF) using fresh semen was established in horses. This facilitated successful capacitation of equine semen allowing to explore novel applications. We aimed to extend this technique to IVF with frozen-thawed semen and intracytoplasmic sperm injection (ICSI), and determine the outcome parameters such as blastocyst production and euploidy rates. A total of 221 oocytes were subjected to either IVF with frozen-thawed semen, ICSI with frozen-thawed semen incubated under capacitating conditions (ICSI cap) or control ICSI with washed frozen-thawed semen. Cleavage and blastocyst rates were assessed and compared across the three groups using one-way ANOVA. Shallow whole genome sequencing was performed on embryos obtained from IVF and ICSI cap. We established a repeatable protocol for IVF with frozen-thawed semen resulting in higher blastocyst rates per collected oocyte (22.4%) when compared to control ICSI (16.4%) (p = 0.048). Furthermore, the use of semen incubated under capacitating conditions for ICSI resulted in higher blastocyst rates than washed sperm, with 69.0%versus 50.0% blastocysts per cleaved embryo (p = 0.03) and 27.8%versus 16.4% blastocysts per collected oocyte (p = 0.04), respectively. It also yielded higher blastocyst rates per cleaved embryo than IVF, with 69.0%versus 45.9% (p = 0.04). The average day of blastocyst formation was not different between the three groups (p = 0.73). Shallow whole genome sequencing revealed no differences in aneuploidy rates between IVF (1/17) and ICSI cap (0/18) (p = 0.49). The incubation of sperm under capacitating conditions for use in ICSI or IVF with frozen-thawed semen may represent a novel method to improve the clinical efficiency of equine IVP embryos, without affecting aneuploidy rates.

An unhealthy lifestyle negatively affects male fertility. Despite this, men that are part of an infertile couple often fail to improve their lifestyle and evidence on influencing factors is limited. To identify facilitators and barriers involved in lifestyle changes of men seeking fertility care and in lifestyle counseling by fertility health care providers (HCPs). A mixed-methods study was performed including semi-structured interviews with 14 men seeking fertility care and seven fertility HCPs. Fifty other men completed a questionnaire evaluating various aspects of lifestyle change. Eligible participants were men part of an infertile couple and met at least one lifestyle criterion: BMI ≥ 25kg/m2, smoker, alcohol use of ≥ 7 units/week, and recreational drug use. Included HCPs provided lifestyle counseling to infertile couples. The most important facilitators for lifestyle changes in men seeking fertility care are the wish to improve their chances to father a child and their partner's support. The most important barriers are stress, a busy life, an unhealthy lifestyle being part of social activities, and normal semen quality. HCPs experienced limited time, unclear and insufficient scientific evidence on lifestyle and male infertility, and lack of uniform care as barriers. Professional responsibility and societal factors were facilitators. HCPs could use these results to improve and personalize lifestyle counseling of men seeking fertility care. For example, by emphasizing the impact of lifestyle on pregnancy loss and offspring in men with normal semen quality. This study is limited by its small sample size and its confinement to a Dutch context. This study identifies previously unknown facilitators and barriers for lifestyle changes in men seeking fertility care. It also reveals barriers experienced by HCPs when counseling male patients about lifestyle. These results should inspire fertility departments to (re)design lifestyle interventions and policies for men seeking fertility care.

Study aimed to obtain insights into physiological responses to immunocastration in pubertal boars by evaluating effects of alternative vaccination protocols and identifying a reliable immunocastration biomarker. It was hypothesized that the timing of gonadotropin-releasing hormone (GnRH) suppression by immunocastration differentially affects reproductive function, as reflected by testicular histology and expression of selected genes related to testicular function, steroid metabolism, and Leydig cell differentiation and function. Effects of three vaccination protocols on antibody titers, testicular histomorphology, and mRNA expression in immunocastrates slaughtered 4, 8, or 12 weeks (IC-4, IC-8, and IC-12, respectively; n = 6 per group) after booster were compared with entire males (EMs; n = 6). Principal component analysis and hierarchical clustering were used to evaluate individual responses and to identify an immunocastration biomarker(s). The selected biomarker was also validated on samples from previous studies. All immunocastrated boars reacted immunologically to vaccination (increased GnRH antibody titer; p < 0.004). There was an increased nucleus-to-cytoplasm ratio in Leydig cells (p < 0.033) and decreased testosterone concentration (p < 0.041) in IC-4 compared with EM, whereas values in IC-8 and IC-12 were intermediate. Hierarchical clustering differentiated immunocastrates with low testosterone (IC-LT; median 0.56ng/mL) and high testosterone (IC-HT; median 7.04ng/mL). In IC-LT, expression levels of FSHR and ESR2 were higher than in IC-HT, and those of LHCGH, STAR and INSL3 were lower compared with IC-HT and EM, whereas expression of ESR1 and HSD17β7 was lower in IC-LT and IC-HT compared with EM (fold change > 1.5 and p < 0.05). There were variable responses to immunocastration in pubertal boars subjected to three vaccination protocols. Suppression of testicular function was most pronounced in boars slaughtered 4 weeks after the booster, whereas progressive recovery occurred in some boars 8 and 12 weeks after the booster. Irrespective of vaccination protocol, INSL3 mRNA expression was a reliable immunocastration biomarker.

Erectile dysfunction (ED) diagnostics are in need of innovation, as traditional tools like the RigiScan face usability challenges and limited clinical adoption. Although several novel sensor systems have been proposed, none have undergone comprehensive clinical validation. This opinion article outlines a structured, three-phase validation framework comprising component validation, system feasibility testing, and clinical validation, aligned with European MDR requirements. Special attention is given to key aspects such as diagnostic accuracy, sleep-stage monitoring, and patient experience. By providing a clear validation pathway, this opinion article aims to support researchers in the development of reliable, patient-friendly, and regulatory-ready tools for non-invasive ED diagnosis.