Association of body mass index on sexual function in women with endometriosis: A cross-sectional study

Abstract

Objective This study aimed to investigate the association between body mass index (BMI) and sexual function, measured by the Female Sexual Function Index (FSFI), in women with endometriosis, adjusting for the number of endometriosis symptoms. Methods A cross-sectional study was conducted using an anonymous online survey distributed via social media. A total of 1,586 women with endometriosis participated. BMI was categorized as <25 kg/m²), 25–30 kg/m², or >30 kg/m². Sexual function was assessed using the FSFI questionnaire, with a cutoff score of <26.55 indicating sexual dysfunction. Statistical analyses included multiple linear regression models adjusted for age, couple status, and the number of endometriosis symptoms. Results The mean FSFI score was 17 (SD: 9), and the mean BMI was 26 (SD: 6) kg/m 2 . Each one-unit increase in BMI was correlated with a small but statistically significant decrease in FSFI score (β = –0.07; 95% CI: –0.15 to –0.01), suggesting limited clinical importance. An inverse U-shaped association was observed, with both low and BMI > 30 kg/m² linked to lower FSFI scores. BMI > 30 kg/m² was significantly correlated with lower FSFI in women with seven endometriosis symptoms (p for interaction = 0.010). Conclusion BMI is significantly correlated with sexual function in women with endometriosis, with both low and high BMI negatively correlating FSFI scores. The association was stronger in women with a higher symptom burden. These findings highlight the need for a multidisciplinary approach integrating metabolic, hormonal, and psychological interventions to improve sexual health among women with endometriosis. Further longitudinal research is needed to explore causality and potential interventions.