Pregnancy induced hypertension (PIH) complicates 6-8% of pregnancies in the United States and accounts for 15% of maternal deaths. It ranks second only to embolic events as a cause of maternal mortality. It also is an important cause of perinatal morbidity and mortality. In pregnant women, two distinct hypertensive disorders are common: Chronic hypertension and pregnancy induced hypertension. Women with chronic underlying hypertension are at risk for PIH. PIH is a multi-organ pathologic state with various subsets:
Risk factors for preeclampsia are noted in the following table:
Ordinarily PIH begins after 20 weeks gestation, but patients with gestational trophoblastic disease (GTD) are an exception; they can develop classic PIH in the first or second trimester.