Study on Influencing Factors of Semen Quality in Fertile Men

Environmental pollution and human fertility: investigating the relationship between PM2.5 exposure and assisted reproductive technology outcomes

OBJECTIVE

To investigate the impact of seasonal variations in particulate matter with an aerodynamic diameter of 2.5 µm or less (PM2.5) exposure on assisted reproductive technology (ART) outcomes.

METHODS

This retrospective study, conducted at the First People's Hospital of Shangqiu, analyzed data from 13,476 patients who underwent ART procedures between February 2018 and December 2022. Patients were categorized based on seasonal PM2.5 exposure levels. A generalized additive model (GAM), linear regression analysis, and multivariate logistic regression were used to assess the relationship between PM2.5 exposure and ART outcomes, including oocyte and embryo quality, pregnancy rates, live birth rates, and miscarriage rates.

RESULTS

Significant differences were observed in oocyte number, metaphase II (MII) oocyte number, transferable embryos, and good-quality embryos across seasonal PM2.5 exposure subgroups. Pregnancy rates and live birth rates also demonstrated statistically significant variations. Linear regression analysis revealed a consistent negative correlation between PM2.5 concentrations and key ART outcomes. Multivariate logistic regression analysis, adjusting for age and seasonal variations, confirmed a significant negative association between PM2.5 exposure and both pregnancy rates (OR = 0.995, 95% CI: 0.994-0.996, p < 0.001) and live birth rates (OR = 0.996, 95% CI: 0.995-0.997, p < 0.001). However, no significant relationship was found between PM2.5 exposure and miscarriage rates. GAM analysis further identified a nonlinear, threshold-like association between pregnancy outcomes and predictive factors, with significantly higher live birth rates observed in spring, summer, and autumn compared to winter.

CONCLUSIONS

The study complements existing evidence that exposure to PM2.5 can lead to decreased success rates of pregnancy and live births, as well as significantly impact the outcomes of ART. Future research should focus on developing strategies to mitigate the adverse effects of environmental pollution on ART success rates.

Artificial intelligence (AI) approaches to male infertility in IVF: a mapping review

BACKGROUND

Male infertility contributes to 20-30% of infertility cases, yet traditional diagnostic and treatment methods face limitations in accuracy and consistency. Artificial intelligence (AI) promises to transform male infertility management within in vitro fertilization (IVF) by enhancing precision and efficiency.

OBJECTIVE

This study aims to map current AI applications in male infertility, evaluate their performance in IVF contexts, identify gaps in research, and propose strategies for clinical adoption.

METHODS

We conducted a mapping review of 14 studies, sourced from PubMed, Scopus, IEEE, and Web of Science up to 2024. Using PRISMA guidelines, we systematically searched titles and abstracts with keywords like "IVF," "AI," and "sperm analysis." Two authors independently screened records, extracted data on AI techniques, sample sizes, and outcomes, and categorized applications through content analysis, resolving discrepancies via consensus.

RESULTS

AI employs tools like support vector machines (SVM), multi-layer perceptrons (MLP), and deep neural networks across six key areas. These include sperm morphology (e.g., SVM with AUC 88.59% on 1400 sperm), motility (e.g., SVM with 89.9% accuracy on 2817 sperm), and non-obstructive azoospermia (NOA) sperm retrieval (e.g., gradient boosting trees [GBT] with AUC 0.807 and 91% sensitivity on 119 patients). AI also predicts IVF success (e.g., random forests with AUC 84.23% on 486 patients) and assesses sperm DNA fragmentation. Research surged since 2021, with 8 of 14 studies (57%) published between 2021 and 2023, reflecting growing interest..

CONCLUSIONS

AI enhances diagnostic accuracy and treatment outcomes in male infertility. Future steps include multicenter validation trials, AI-driven sperm selection for IVF/ICSI, and standardized methods to ensure clinical reliability. Addressing ethical concerns like data privacy will further enable AI to improve IVF success globally.

Per- and Polyfluoroalkyl Substances in Semen Associated with Repeated Measures of Semen Quality in Healthy Adult Men

Although epidemiological studies have explored the association between poly- and perfluoroalkyl substances (PFAS) concentrations and semen quality, existing findings are often inconsistent. Our work aimed to explore the association of PFAS in plasma and semen with repeated measures of semen quality parameters in healthy adults. Plasma was collected at the initial recruitment and semen was collected at least once within five predetermined intervals during an approximately 3-month period. Semen volume, concentration, motility, and total sperm count were measured in each semen specimen. PFAS was measured in individual plasma samples (n = 1252) and pooled semen samples (n = 1019) from multiple collections (or in a single semen sample if no multiple collection was available). The results reveal seminal perfluorooctanoic acid, perfluorooctanesulfonic acid, perfluorohexanesulfonic acid, and 6:2 chlorinated polyfluoroalkyl ether sulfonate were significantly associated with decreased sperm progressive motility and total motility, while multiple seminal PFAS were positively associated with sperm concentration and total sperm count. By contrast, null associations were observed between plasma PFAS and semen quality. Our study provides epidemiological evidence that PFAS exposure may affect male fertility and seminal PFAS should be measured for precise assessment of the impact of PFAS on male reproductive performances.

Association of diet and lifestyle factors with semen quality in male partners of Chinese couples preparing for pregnancy

BACKGROUND

Semen quality significantly influences conception, and its preservation is crucial for couples seeking pregnancy. We investigated dietary and lifestyle risk factors impacting semen quality.

METHODS

A total of 466 males from the Guangzhou Women and Children's Medical Center's pre-pregnancy consultation clinic were recruited between January 2021 and March 2023 for inclusion. Semen analysis was performed, and diet and lifestyle data were gathered via questionnaire. Logistic regression was utilized to examine the link between diet, lifestyle variables, and semen quality.

RESULTS

Smoking worsened progressive sperm motility (38.0% vs. 36.0%, t = 2.262; P = 0.049). Alcohol consumption impaired progressive motility (40.5 ± 17.8% vs. 34.7 ± 16.1%, t = 3.396; P < 0.001) and total motility (56.0% vs. 64.0%; P = 0.001). Using plastic beverage bottles for oil or seasonings lowered sperm concentrations (40.4% vs. 59.0% vs. 65.5%; P = 0.032). A sweet diet correlated with higher total sperm motility (55.0% vs. 60.0%, 62.0% vs. 63.2%; P = 0.017). Higher milk product intake improved sperm concentration (41.6106 vs. 63.7106 vs. 66.1*106; P = 0.021) and motility (54.5% vs. 56.0% vs. 63.0%; P = 0.033). More frequent egg consumption increased semen volume (3.1 mL vs. 3.8 mL vs. 4.0 mL; P = 0.038). Roughage intake enhanced sperm concentration (160.8106 vs. 224.6106; P = 0.027), and adequate sleep improved progressive sperm motility rate (35.4% ± 18.2% vs. 40.2 ± 16.3%, F = 3.747; P = 0.024) and total motility (52.7% vs. 61.5%; P = 0.013). The regression model showed that using plastic containers for condiments was a protective factor for semen volume (OR: 0.12; CI 0.03-0.55; P = 0.006), sperm concentration (OR: 0.001, CI 0.00-0.30; P = 0.012), and count (OR: 0.12, CI 0.03-0.48; P = 0.003). Milk and egg consumption were also protective for semen volume (OR: 0.18, CI 0.06-0.51; P = 0.001 and OR: 0.11, CI 0.03-0.55; P = 0.006, respectively), while sufficient sleep benefitted total sperm motility (OR: 0.47, CI 0.24-0.95; P = 0.034).

CONCLUSIONS

Smoking and drinking, type of condiment container, diet preference, sleep duration, and milk, roughage, and egg consumption may reduce semen quality.

A retrospective cohort study of geographic differences in the semen of 1,012 sperm donors in China

Background

Male reproductive health has become a serious public health concern, and semen quality is essential to male reproduction. We aimed to investigate geographical differences in the semen quality of sperm donors from northern and southern China by enrolling donors across the country.

Methods

A total of 1,012 sperm donors were enrolled in this study between 2015 and 2019. Donors were first divided into two parts based on their birthplace according to the "Qinling-Huaihe" line, and secondly, by their residential latitude. Finally, donors were re-classified into two groups (typically north and south) which contained 667 samples.

Results

Statistically significant differences in sperm concentration were observed among men from different latitudes in China (P=0.04). The sperm concentrations of males from 18° to 27° north latitude were significantly lower than those from 36° to 45° and 45° to 54° [median 131, 134, and 146, respectively, P=0.021 (18° to 27° vs. 36° to 45°) and P=0.01 (18° to 27° vs. 45° to 54°)].

Conclusion

We hypothesize environmental pollution and mental stress due to the increased population size may be the main factors underlying differences in the sperm quality of men in northern and southern China.

Fertility Awareness-Based Methods for Women's Health and Family Planning

Background

Fertility awareness-based methods (FABMs) educate about reproductive health and enable tracking and interpretation of physical signs, such as cervical fluid secretions and basal body temperature, which reflect the hormonal changes women experience on a cyclical basis during the years of ovarian activity. Some methods measure relevant hormone levels directly. Most FABMs allow women to identify ovulation and track this "vital sign" of the menstrual or female reproductive cycle, through daily observations recorded on cycle charts (paper or electronic).

Applications

Physicians can use the information from FABM charts to guide the diagnosis and management of medical conditions and to support or restore healthy function of the reproductive and endocrine systems, using a restorative reproductive medical (RRM) approach. FABMs can also be used by couples to achieve or avoid pregnancy and may be most effective when taught by a trained instructor.

Challenges

Information about individual FABMs is rarely provided in medical education. Outdated information is widespread both in training programs and in the public sphere. Obtaining accurate information about FABMs is further complicated by the numerous period tracking or fertility apps available, because very few of these apps have evidence to support their effectiveness for identifying the fertile window, for achieving or preventing pregnancy.

Conclusions

This article provides an overview of different types of FABMs with a published evidence base, apps and resources for learning and using FABMs, the role FABMs can play in medical evaluation and management, and the effectiveness of FABMs for family planning, both to achieve or to avoid pregnancy.