Impact of oral contraceptive treatment duration on ovarian reserve markers and pain in women with ovarian endometrioma: a retrospective cohort study.

BACKGROUND: Oral contraceptive pills (OCPs) are widely used for symptom control in women with ovarian endometrioma; however, their impact on ovarian reserve and the optimal duration of treatment remain uncertain, particularly for women planning future fertility. OBJECTIVE: To evaluate the association between oral contraceptive pill (OCP) treatment duration and ovarian reserve markers, pain scores, and endometrioma size in women with ovarian endometrioma. METHODS: This retrospective cohort study included 210 reproductive-aged women diagnosed with ovarian endometrioma between August 2018 and August 2025. Women were grouped according to OCP use as part of routine clinical management: Group A (no OCP, n = 112) and Group B (OCP use for 3–6 months, n = 98). Ovarian reserve markers [anti-Müllerian hormone (AMH) and antral follicle count (AFC)], endometrioma size, and pain scores assessed by visual analogue scale (VAS) were compared between groups at baseline, 3 months, and 6 months. Within-group comparisons between 3 and 6 months were also performed among OCP users. RESULTS: Baseline demographic and clinical characteristics were comparable between groups. At 3 months, OCP users showed significantly lower VAS pain scores compared with non-users (p = 0.032), while ovarian reserve markers were significantly lower in the OCP group [AMH (p = 0.043) and AFC (p = 0.022)]. At 6 months, endometrioma size (p = 0.048) and pain scores (p = 0.012) remained significantly lower in the OCP group. AMH (p = 0.021) and AFC (p = 0.011) also remained significantly lower among OCP users. No significant differences were observed between 3- and 6-month measurements within the OCP group for any outcome. CONCLUSION: In women with ovarian endometrioma, oral contraceptive use was associated with improvements in pain and reduction in cyst size, accompanied by lower ovarian reserve marker levels during treatment, likely reflecting pharmacologic suppression. Extending OCP treatment beyond three months was not associated with additional clinical benefits, highlighting the importance of individualized treatment duration, particularly for women planning future fertility.