Desogestrel only contraceptive pill versus sequential contraceptive vaginal ring in the treatment of rectovaginal endometriosis infiltrating the rectum: a prospective open-label comparative study

OBJECTIVE: To compare the efficacy of desogestrel only contraceptive pill (group D) or combined sequential contraceptive vaginal ring (group SN) in treating symptoms caused by bowel endometriosis. DESIGN: This patient preference study was performed between January 2008 and June 2011. MATERIALS AND METHODS: Patients were treated with desogestrel only contraceptive pill or combined sequential contraceptive vaginal ring for 12 months. The primary endpoint of the study was the rate of satisfied patients at 12-month follow-up. The changes in pain symptoms, gastroin- testinal symptoms and in the volume of the nodules were secondary end- points. RESULTS: One hundred and forty-three women with rectovaginal endo- metriosis infiltrating the rectum were enrolled in the study. At 12-month follow-up, the rate of satisfied patients was higher in group D than group SN (p 1⁄4 0.004). Both pain and gastrointestinal symptoms (such as diar- rhoea and intestinal cramping) improved more in patients of group D than in those of group SN. When only changes in gastrointestinal symp- toms were considered, 50.0% of patients in group D and 31.3% of those in group SN were satisfied (p 1⁄4 0.037). At the end of treatment, the reduction of the mean volume of the endometriotic nodules was significant in both group D (26.4%) and group SN (28.1%). Furthermore, the percent- ages of patients who discontinued the therapy after the completion of the study and of those who decided to undergo surgery were similar between the two study groups. CONCLUSION: Both hormonal therapies are efficacious in treating symptoms caused by rectovaginal endometriosis infiltrating the rectum. Patient satisfaction was higher with desogestrel than with vaginal ring.