Metformin in polycystic ovary syndrome: systematic review and meta-analysis

To assess the effectiveness of metformin in improving clinical and biochemical features of polycystic ovary syndrome.

Systematic review and meta-analysis. DATA SOURCES: Randomised controlled trials that investigated the effect of metformin compared with either placebo or no treatment, or compared with an ovulation induction agent. SELECTION OF STUDIES: 13 trials were included for analysis, including 543 women with polycystic ovary syndrome that was defined by using biochemical or ultrasound evidence. MAIN OUTCOME MEASURE: Pregnancy and ovulation rates. Secondary outcomes of clinical and biochemical features of polycystic ovary syndrome.