Inverse association between obesity and intestinal endometriosis: Findings from a cross-sectional study

This study evaluates the association between obesity and the presence of bowel endometriosis in patients undergoing surgery.

A retrospective cross-sectional observational study was conducted with patients treated between September 2023 and December 2024, at a specialized endometriosis outpatient clinic of a tertiary hospital in Rio de Janeiro, Brazil. Women who underwent surgery for histopathological confirmation of deep endometriosis were included. The outcome was bowel endometriosis, defined as a lesion >1 cm located in the rectosigmoid region. Preoperative weight and height were measured, and obesity was defined according to World Health Organization body mass index (BMI) criteria. The association between obesity and the outcome was assessed using multivariable logistic regression, adjusting for potential confounders. A P-value <0.05 was considered statistically significant.

A total of 223 women with histologically confirmed deep endometriosis were included, of whom 24.2% had bowel involvement. In the multivariable logistic regression, after adjusting for age and number of cesarean deliveries, body weight was independently associated with a lower likelihood of bowel lesions (odds ratio [OR]: 0.97; 95% confidence interval [CI]: 0.94-0.99; P = 0.031). The number of cesarean deliveries was also inversely associated with the outcome (OR: 0.39; 95% CI: 0.21-0.71; P = 0.002).

Although higher body weight was associated with a lower chance of bowel involvement, these results should be interpreted cautiously given the cross-sectional nature of the study and the limitations of BMI and body weight as measures of adiposity. Future studies incorporating more precise anthropometric assessments (e.g., bioimpedance, body fat percentage, or abdominal circumference) are warranted.