Metformin may not help neonatal birth weight

New research suggests that the diabetes drug metformin may not help obese pregnant women have normal-weight babies. Researchers evaluated 400 obese women (with a body-mass index higher than 35) without diabetes who received metformin 3 g/daily or placebo from 12–18 weeks of gestation until delivery. The primary outcome was a decrease in the median neonatal birth-weight z score by 0.3 SD, with secondary outcomes including maternal gestational weight gain and the incidence of gestational diabetes and of preeclampsia, and the incidence of adverse neonatal outcomes.