Cases were divided into three groups: group A, 40 women who stopped metformin between 4-16 weeks of pregnancy; group B, 20 women who received metformin up until 32 weeks of gestation; and group C; 45 women who continued metformin throughout pregnancy. All the groups were matched by age, height and weight. Comparison was in terms of early and late pregnancy complications, intrauterine growth restriction and live birth rates. In groups A, B and C the rate of pregnancy-induced hypertension/pre-eclampsia was 43.7%, 33% and 13.9% respectively (P < 0.020)...
So this is a preliminary study, but it suggests that maybe if PCOS patients use metformin throughout pregnancy, it will lower their risk of preeclampsia.
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