Postoperative Cyclic Oral Contraceptive Use for the Prevention of Endometrioma Recurrence

Ovarian endometriotic cyst (endometrioma) is one of the most common endometriotic lesions, and conservative laparoscopic surgery is the treatment of choice. However, the recurrence after surgery is common. As repetitive surgery leads to morbidities and ovarian function decrease, recurrence after surgery frustrates both patients and clinicians. In this aspect, medical treatments have been offered after surgery to prevent or delay the recurrence. Gonadotropin-releasing hormone agonist (GnRHa) is frequently used in women with advanced endometriosis, but the efficacy is rather controversial. On the other hand, it has been demonstrated that oral contraceptives (OCs) could reduce or delay endometrioma recurrence, but data are still limited. Consequently, no one type of postoperative medical therapy has been shown to be superior in reducing the recurrence of endometrioma. The rationale of postoperative medical therapy is that it could eradicate microscopic lesions which were not found and not treated sufficiently during surgery. Therefore, the maintenance of strongly suppressed condition induced by postoperative GnRHa treatment by addition of OCs could be a promising treatment to prevent the recurrence, but it has not been widely investigated. We performed this retrospective cohort study to evaluate the efficacy of cyclic monophasic low-dose OCs as a maintenance therapy after GnRHa treatment for the suppression of endometrioma recurrence.