Objective: To compare the efficacy of metformin with that of lifestyle changes in patients with polycystic ovary syndrome (PCOS).
Design: Prospective, randomized clinical trial of 40 women with PCOS to analyze the effects of metformin and lifestyle intervention treatments on menstrual pattern and hormone and metabolic profile. The duration of treatment was 6 months. Statistical analysis was done using Student's t-test.
Results: Fifteen women in the metformin group and 12 in the lifestyle changes group completed the study. The menstrual pattern improved by ~67% in both groups. There was a significant decrease in waist circumference in the lifestyle changes group (101.8 ± 3.9 and 95.1 ± 3.6, at baseline and at 6 months of treatment, respectively; p < 0.001) and in body mass index (BMI) in both groups. The predictor of menstrual pattern improvement was BMI.
Conclusions: Both metformin and lifestyle changes may increase the number of menstrual cycles in PCOS. This effect was related to a decrease in BMI.