Continuous low-dose oral contraceptive in the treatment of colorectal endometriosis evaluated by rectal endoscopic ultrasonography.

Objective: Limited attention has been focused on the medical treatment of bowel endometriosis. This study evaluates the efficacy of administration of a continuous low-dose oral contraceptive in treating pain and other symptoms associated with colorectal endometriotic nodules, as evaluated by rectal endoscopic ultrasonography.

Design: Prospective observational study.

Setting: Academic Department of San Raffaele Scientific Institute, Obstetrics and Gynecology Unit.

Population: Symptomatic women of reproductive age (n=26) with colorectal nodules infiltrating at least the bowel muscularis propria and without a stenosis >50%. In 31% of the patients, endoscopic ultrasonography permitted diagnosis of nodules located more than 10 cm from the anal rim.

Methods: Patients received a continuous low-dose oral contraceptive containing 15 μg ethinylestradiol and 60 μg gestodene for 12 months. Subjective symptoms were prospectively evaluated, and nodule volumes were monitored using endoscopic ultrasonography.

Main Outcome Measures: Nodule measurements were performed at baseline and after 12 months of treatment. Symptoms at the start and after 12 months were evaluated.

Results: A significant improvement in the intensity of all the considered symptoms (dysmenorrhea, non-menstrual pelvic pain, deep dyspareunia and painful defecation) was seen when evaluated by a visual analog scale. A reduction in terms of both diameter (mean reduction 26%) and volume of the nodules (mean reduction 62%) was observed after a 12 month period.

Conclusions: A continuous low-dose oral contraceptive therapy may reduce bowel endometriosis-associated symptoms. In addition, this therapy induces a significant volumetric reduction of colorectal plaques when evaluated by endoscopic ultrasonography.