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.

Current Knowledge on Endometriosis Etiology: A Systematic Review of Literature.

OBJECTIVE: To review the mechanisms of endometriosis development, including those related to epigenetic mutations, cellular dysregulation, inflammatory processes, and oxidative stress. METHODS: A systematic literature review regarding current aspects of endometriosis etiology, genesis and development was performed using the PubMed, Google Scholar, and eLibrary databases. Keywords included endometriosis, etiology, development, genesis, associations and mechanisms. A multilingual search was performed. RESULTS: Several mechanisms underline the pathophysiological pathways for endometriosis development. Epigenetic mutations, external and internal influences, and chronic conditions have a significant impact on endometriosis development, survival and regulation. Several historically valid theories on endometriosis development were discussed, as well as updated findings. CONCLUSION: Despite recent advances, fundamental problems in understanding endometriosis remain unresolved. The identification of unknown circulating epithelial progenitors or stem cells that are responsible for epithelial growth in both the endometrium and endometriotic foci seems to be the next step in solving these questions.