The impact of adjunctive metformin to progesterone for the treatment of non-atypical endometrial hyperplasia in a randomized fashion, a placebo-controlled, double blind clinical trial.

Objective: Endometrial hyperplasia (EH) is a premalignant neoplasm. Most recently, metformin has been suggested as an adjuvant medication for treating of EH with better outcome. Recent evidence has suggested that metformin has anticancer activity by inhibiting cell proliferation and tumor growth. The aim of this study was to evaluate the effect of metformin plus megestrol acetate versus megestrol acetate alone on patient with EH without atypia.

Study Design: This double blind placebo-controlled clinical trial was conducted among 60 women with EH without atypia. Participants were allocated to two equal groups. Treatment group (M + M) received 40 mg megestrol acetate for 14 days of one month and 1000 mg metformin daily for three months. In placebo group (M + P) each patient received the same dose of megestrol acetate plus two tablets of placebo. Endometrial biopsy was performed in all patients three weeks after the last day of medication RESULTS: Data were evaluated based on 29 and 27 women in the M + M group and M + P group, respectively. After 3 months of therapy 27 (93.1 %) women in M + M group had not EH and responded to treatment, which was statistically higher than the rate of response (19 women, 70.4 %) in M + P group.

Conclusions: This study showed that megestrol plus metformin was significantly better than megestrol alone for the treatment of endometrial hyperplasia without atypia.