Medical management of recurrent endometrioma with long-term norethindrone acetate

PURPOSE: Evaluate the efficacy of norethindrone acetate in the resolution of symptoms and regression of recurrent endometrioma. PATIENTS AND METHODS: Retrospective chart review at SUNY Downstate Medical Center of patients with a history of surgical excision of endometrioma (with histological confirmation) and recurrent endometrioma (demonstrated by strict sonographic criterion of endometrioma) who were willing to undergo follow-up. Patients were prescribed norethindrone acetate to be taken daily with follow-up sonograms until cysts regressed. Statistical analysis included Student’s t-test and a simple linear regression model to assess cyst regression over time during treatment. RESULTS: Degree of pain was significantly lower on treatment when compared to baseline (P < 0.00001). Cyst size was significantly smaller in as little as 3 months (P < 0.0001). Average rate of regression with continuous treatment was 0.025 ± 0.015 cm/day. Total mean ± standard deviation regression time is 10.28 ± 8.25 months. CONCLUSION: Norethindrone acetate was effective in eradicating symptoms and producing complete regression of recurrent endometriomas. It should be considered for patients who are likely to adhere to a prolonged treatment regimen and comply with recommendations for surveillance with serial sonograms.