Effect of Dienogest therapy on the size of the endometrioma

Studies have been published on the efficacy of Dienogest in the management of pain symptoms in endometriosis. Nonetheless, few data are available on the reducing effect on endometrioma's size. The aim of the study was to evaluate if Dienogest could determine significant changes in size, as well as in symptoms. In this prospective observational study, patients were enrolled with pain symptoms and at least one endometrioma diagnosed via TV-US. The volume of the endometrioma and pain symptoms was measured according to the LxDxWx0.5233 formula and VAS, respectively. Dienogest 2 mg was administered daily. Follow-up visits were scheduled after 6 and 12 months of treatment to assess changes in patients' symptoms and endometrioma's volume. Seventy patients were enrolled, 63 patients completed a 6-month treatment. The reduction of the mean volume after 6 months was 66.71%. Fifty-eight patients completed the 12 month-treatment. The reduction of the mean volume after 12 months was 76.19%. Dysmenorrhea showed a 74.05% reduction after 6 months and a 96.55% reduction after 12 months. Patients reported a reduction in dyspareunia and chronic pelvic pain of 42.71% and 48.91% after 6 months and 51.93% and 59.96% after 12 months, respectively. Dienogest leads to a statistically significant reduction of endometrioma's volume and pain symptoms.