Abstract
BACKGROUND: Obesity has become a major global public health challenge, closely associated not only with metabolic and cardiovascular disorders but also with male sexual dysfunction. Emerging evidence suggests that bariatric surgery may improve sexual function in obese men by enhancing hormonal balance, reducing visceral adiposity, and restoring endothelial function. However, existing studies show strong heterogeneity in design, surgical approaches, and sample sizes, underscoring the need for an updated systematic review and meta-analysis. OBJECTIVE: To systematically evaluate and meta-analyze the effects of bariatric surgery on sexual function and related hormonal levels in obese men. METHODS: PubMed, Web of Science, Embase, and the Cochrane Library were systematically searched for relevant studies published up to June 2025. A random-effects model was applied to pool effect sizes, and heterogeneity was assessed using the I² statistic. Changes in International Index of Erectile Function (IIEF) scores and hormone levels before and after surgery were evaluated. Subgroup analyses, sensitivity analyses, and publication bias assessments were conducted, with all analyses performed using Stata 17.0. RESULTS: A total of 21 studies involving 695 participants were included. Pooled analyses showed significant improvements in both IIEF-5 and IIEF-15 total scores after surgery (MD = 6.45 and 9.03, respectively; p < 0.001), indicating overall enhancement in sexual function. Domain-specific results demonstrated significant improvements in erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction, with erectile function showing the greatest improvement (SMD = 0.76); however, differences between domains were not statistically significant. Regarding hormonal outcomes, total testosterone increased significantly after surgery (MD = 8.21, p < 0.001), whereas free testosterone showed no significant change. Body mass index (BMI) decreased markedly (MD = -13.86, p < 0.001). Subgroup analyses consistently supported the beneficial effects of surgery. Sensitivity analyses confirmed the robustness of the results, and Egger's test indicated no significant publication bias. CONCLUSIONS: Bariatric surgery significantly improves sexual function in obese men, particularly erectile function, and increases total testosterone levels. These findings suggest that, beyond weight reduction and metabolic improvement, bariatric surgery may also play an important role in enhancing sexual health and overall quality of life. Further studies, including randomized controlled trials with standardized hormonal assessment and extended follow-up, are required to establish the causal relationship between surgery and sexual function.