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.