Influence of Male Body Mass Index on Sperm Quality and In Vitro Fertilization Success Rates.

PURPOSE: The global increase in obesity has raised significant concern regarding its impact on male fertility, particularly in the context of in vitro fertilization (IVF). The present study investigated the associations among male body mass index (BMI), sperm quality, IVF outcomes, and embryo development. The regulatory roles of circular RNA MYH9 (circMYH9), microRNA-133a-3p (miR-133a-3p), and C-X-C chemokine receptor type 4 (CXCR4) were also examined to provide novel insights into improving the clinical management of male infertility.

MATERIALS AND

METHODS

A total of 57 men undergoing IVF treatment were recruited and categorized into normal-weight, overweight, and obese groups based on BMI classification. Sperm parameters, fertilization rate, embryo development, and pregnancy outcomes were systematically compared among the groups. Expression levels of circMYH9, miR-133a-3p, and CXCR4 in sperm were quantified using molecular assays, and their correlations with clinical and laboratory indicators were statistically analyzed.

RESULTS

Higher BMI was significantly associated with reduced sperm concentration, total sperm count, motility, and progressive motility (p<0.05), as well as a lower clinical pregnancy rate during IVF (p<0.05). At the molecular level, higher expression of circMYH9 and CXCR4 was positively correlated with fertilization rate and high-quality embryo formation, whereas elevated miR-133a-3p expression was negatively correlated with these outcomes. Moreover, BMI showed negative correlations with circMYH9 and CXCR4 expression and a positive correlation with miR-133a-3p expression (all p<0.01).

CONCLUSIONS

Elevated male BMI adversely affects sperm quality and IVF outcomes, potentially mediated through dysregulation of the circMYH9/miR-133a-3p/CXCR4 molecular network. These findings indicate that targeted weight management and molecular modulation may represent effective strategies to improve reproductive outcomes in obese men, with important implications for clinical practice.