Effects of dienogest treatment on endometrioma-related clinical symptoms and endometrioma size: retrospective cohort study.

Background: To evaluate the efficacy and long-term safety of treatment with dienogest in patients with endometrioma. Methods: Patients with endometrioma-related chronic pelvic pain were included in this retrospective study from March 2018 to March 2023. Enrolled patients received 2 mg of dienogest once daily. Data from 180 patients were analyzed. Group 2 ( Results: Findings at T0 (baseline) and T1 (sixth month) visits, in which the entire study cohort could be included, were compared. Then, patients who continued treatment at visits every 6 months after T1 (>12 months) were compared one by one with the findings at T0. The reduced libido was 4.3 times higher in the long-term group, but the weight gain was higher in the short-term group. Analysis within all patients and individual groups (short term vs. long term) showed a significant decrease in endometrioma size and VAS scores between T0 and T1 visit findings. Similarly, the findings of T2 and each subsequent visit of the patients in the long-term group were compared with the initial findings and a significant reduction in endometrioma size and VAS scores was observed. Conclusion: Although the effectiveness of dienogest treatment for endometrioma seems to begin in the sixth month, its effectiveness maximizes in patients whose treatment duration is over 1 year.