Chronic hypertension in pregnancy.

Pregnant women with chronic hypertension are at risk for maternal and perinatal morbidity. Careful assessment and management of these patients during pregnancy are the keys to reducing maternal and fetal complications. Antihypertensive treatment should be used in women with high-risk chronic hypertension, whereas drug therapy does not improve pregnancy outcome in women at low risk. Prophylactic low-dose aspirin started early in pregnancy in women with chronic hypertension is not effective in reducing the frequency of superimposed preeclampsia and should be avoided.