Metformin is a reasonable first-line treatment option for non-obese women with infertility related to anovulatory polycystic ovary syndrome - A meta-analysis of randomised trials

Background: There are differences in opinion as to whether metformin should play a role in the primary treatment of anovulatory infertility for women with polycystic ovary syndrome (PCOS). Aim: The aim of this study was to ascertain the best available evidence comparing metformin versus clomiphene treatment for non-obese women with anovulatory infertility related to PCOS. Methods: Meta-analysis of available data from randomised controlled trials that examined metformin versus clomiphene for the subgroup of women in the lower body mass index (BMI) range (primarily non-obese). Primary outcomes were clinical pregnancy and live birth. Results: For women with BMI <= 30-32 kgm(2), clinical pregnancy rates were 36.7% (52/42) for metformin and 35.7% (51/43) for clomiphene; live birth rates were 30.3% (43/42) for metformin and 30.8% (44/43) for clomiphene. Conclusion: The available randomised trial data show no significant difference in effectiveness of metformin versus clomiphene as ovulation induction agents for non-obese women with anovulatory PCOS. Metformin and clomiphene are both suitable options for first-line treatment.