Effects of metformin-diet intervention before and throughout pregnancy on obstetric and neonatal outcomes in patients with polycystic ovary syndrome

Prospectively assess whether metformin/diet pre-conception and throughout pregnancy would safely reduce first trimester miscarriage and improve pregnancy outcomes in women with polycystic ovary syndrome (PCOS).In 76 PCOS women, first pregnancy miscarriage and live birth were compared before and on metformin/diet, started 6.8 months (median) before conception, continued throughout pregnancy. On metformin 2-2.55 g/day, low glycemic index diet, first pregnancy outcomes in PCOS were compared with 156 community obstetric practice women (controls).Live births, miscarriage, birth <37 weeks gestation, gestational diabetes, pre-eclampsia, fetal macrosomia.In 76 PCOS women before metformin-diet, there were 36 miscarriages (47%) and 40 live births vs. 14 (18%) miscarriages and 62 live births on metformin-diet 6.8 months before conception and throughout pregnancy, p = 0.0004, OR 3.99, 95% CI 1.91-8.31. On metformin-diet, PCOS women did not differ (p > 0.08) from controls for birth <37 weeks gestation, gestational diabetes, pre-eclampsia, or fetal macrosomia.Metformin-diet before and during pregnancy in PCOS reduces miscarriage and adverse pregnancy outcomes. Study limitation: individual benefits of the diet alone and diet plus metformin could not be assessed separately. Randomized, controlled clinical trials now need to be done with a larger number of patients.