Prolonged cyclical and continuous regimens of dydrogesterone are effective for reducing chronic pelvic pain in women with endometriosis: results of the ORCHIDEA study

OBJECTIVE: To compare the effectiveness of two different treatment regimens of dydrogesterone in the management of endometriosis-related chronic pelvic pain. DESIGN: Observational, prospective cohort study over six months. SETTING: Twenty gynecology clinics in the Russian Federation. PATIENT(S): Three hundred fifty women from 18 to 45 years of age with endometriosis and chronic pelvic pain with or without dysmenorrhea. INTERVENTION(S): Dydrogesterone 10 mg 2 or 3 times daily, either between the 5th and 25th days of the menstrual cycle (prolonged cyclical treatment regimen) or continuously (continuous treatment regimen). For all patients, the data cutoff was at six months of treatment. MAIN OUTCOME MEASURE(S): Intensity of chronic pelvic pain on the 11-point numerical rating scale (after 6 months). RESULT(S): A marked reduction in chronic pelvic pain was observed with both the prolonged cyclical and continuous treatment regimens (mean ± standard deviation change from baseline -3.3 ± 2.2 and -3.0 ± 2.2, respectively), with no significant difference between the two groups. With both regimens, patients experienced significant improvements in the intensity of chronic pelvic pain, number of days in which analgesics were required, severity of dysmenorrhea, sexual well-being, and health-related quality-of-life parameters. A favorable safety profile of dydrogesterone was confirmed, and no serious adverse drug reactions were reported during the study. CONCLUSION(S): Prolonged cyclical and continuous treatment regimens of dydrogesterone therapy both demonstrated a pronounced and similar reduction in the severity of chronic pelvic pain and dysmenorrhea and led to marked improvements in all study parameters related to quality of life and sexual well-being. REGISTRATION NUMBER: NCT03690765.