Long-term therapy with dienogest or other oral cyclic estrogen-progestogen can reduce the need for ovarian endometrioma surgery

Background: Almost 10% of women in reproductive age are diagnosed with ovarian endometriomas and can experience symptoms and infertility disorders. Ovarian endometriomas can be treated with medical or surgical therapy. Objective: To assess whether long-term therapy with dienogest or oral cyclic estrogen-progestogens is effective in reducing the size of ovarian endometriomas, alleviating associated symptoms, and reducing the requirement for surgery. Design: Prospective non-interventional cohort study. Methods: We enrolled childbearing women diagnosed with ovarian endometriomas. We collected demographic, clinical, and surgical data, including the evaluation of ovarian endometrioma-associated symptoms and pain using the visual analog scale. We grouped the women according to treatment regimen into dienogest, estrogen-progestogens, and no-treatment. Patient's assessment was performed at baseline and after 12 months evaluating the largest ovarian endometrioma diameter (in millimeters) and the associated symptoms. Furthermore, we analyzed the impact of hormonal treatment in a sub-group of women fulfilling at baseline the criteria for a first-line surgical approach (ovarian endometrioma > 30 mm with visual analog scale > 8 or ovarian endometrioma > 40 mm before assisted reproductive treatments or any ovarian endometrioma(s) > 60 mm). Results: We enrolled 142 patients: 62, 38, and 42 in dienogest, estrogen-progestogens, and no-treatment groups, respectively. No significant differences were found regarding baseline characteristics. After 12 months, the mean largest ovarian endometrioma diameter increased in the no-treatment group (31.1 versus 33.8; p < 0.01), while a significant reduction was registered in the dienogest (35.1 versus 25.8; p < 0.01) and estrogen-progestogens (28.4 versus 16.7; p < 0.01) groups; no significant difference in ovarian endometrioma diameter reduction between these two latter groups was noted (p = 0.18). Ovarian endometrioma-associated symptoms and pain improved in dienogest and estrogen-progestogens groups, with a significantly greater effect for dienogest than for estrogen-progestogens for dysmenorrhea (74% versus 59%; p < 0.01). In the sub-group of women eligible for first-line surgery at baseline, long-term treatment with dienogest and estrogen-progestogens reduced surgical eligibility by 30%. Conclusions: Decreased mean largest ovarian endometriomas'diameter after 12 months and reduction of the need for surgical treatment by 30% were observed in dienogest and estrogen-progestogens groups. Long-term treatment with dienogest had a greater effect in alleviating dysmenorrhea and pain.