To study the incidence of spontaneous abortions, congenital malformations, neonatal and maternal hypoglycemia after metformin therapy in pregnancy.

Prospective study.

Outpatient.

56 women previously oligomenorrheic, nondiabetic women with polycystic ovarian syndrome, who conceived while on metformin.

Metformin 1 to 1.5 gm/day throughout pregnancy.

Incidence of 1st trimester abortions, gestational diabetes, teratogenicity and maternal complications, like gastritis and hypoglycemia.

On metformin, the incidence of 1st trimester abortion was 11% and the incidence of gestational diabetes was 7%, which is much lower than the incidence otherwise cited for PCOS women. No major congenital abnormalities were observed.

Metformin therapy in pregnancy reduces the otherwise high incidence of 1st trimester abortions, and gestational diabetes in PCOS women is tolerated well and is not found to be teratogenic.