At 24-48 hours after delivery, women who are eligible for participation will be approached and consented to the study. Maternal weight will be measured and 20ml of maternal blood will be obtained to assess glucose control and lipid profile. Women will be counseled regarding diet, exercise and glucose control. Data including maternal demographics, clinical characteristics and neonatal outcomes will be collected. At 3 weeks postpartum, a research nurse will contact the subject via telephone call to inquire about adverse or side effects, ability to take the prescribed medication (metformin or placebo), and to answer questions about the study. At 6 weeks postpartum, maternal weight will be measured , blood will be obtained and side effects will be evaluated again. Finally, a satisfaction survey will be completed.
