ABSTRACT: Radiofrequency endometrial ablation (REA) is currently a second line treatment in women with heavy menstrual bleeding (MHB) if medical therapy (MTP) is contraindicated or unsatisfactory. Our objective is to compare the effectiveness and cost burden of MTP and REA in the initial treatment of HMB.We performed a randomized trial at Mayo Clinic Rochester, Minnesota. The planned sample size was 60 patients per arm. A total of 67 women with HMB were randomly allocated to receive oral contraceptive pills (Nordette ®) or Naproxen (Naprosyn®) (n = 33) or REA (n = 34). Primary 12-month outcome measures included menstrual blood loss using pictorial blood loss assessment chart (PBLAC), patients' satisfaction, and Menorrhagia Multi-Attribute Scale (MMAS). Secondary outcomes were total costs including direct medical and indirect costs associated with healthcare use, patient out-of-pocket costs, and lost work days and activity limitations over 12 months.Compared to MTP arm, women who received REA had a significantly lower PBLAC score (median [Interquartile range, IQR]: 0 [0-4] vs. 15 [0-131], p = 0.003), higher satisfaction rates (96.8%vs.63.2%, p = 0.003) and higher MMAS (median [IQR]: 100 [100-100] vs. 100 [87-100], p = 0.12) at 12 months. Direct medical costs were higher for REA ($5,331vs.$2,901, 95% confidence interval (CI) of mean difference:$727,$4,852), however, when indirect costs are included, the difference did not reach statistical significance ($5,469 vs. $3,869, 95% CI of mean difference:-$339, $4,089).For women with heavy menstrual bleeding, initial radiofrequency endometrial ablation compared to medical therapy offered superior reduction in menstrual blood loss and improvement in quality of life without significant differences in total costs of care.NCT01165307.