Epidemiology of Pregnancy-Related Hypertension

Preeclampsia−eclampsia is a leading cause of maternal mortality and morbidity. Eclampsia has decreased dramatically in the last several decades in high-income countries, probably reflecting improvements in medical care rather than a change in the disease’s natural history. Conversely, preeclampsia’s frequency is increasing in the United States (25% between 1987 and 2004), although it may be decreasing in other high-income countries. The pregnancy-specific risk of preeclampsia is increased in women with nulliparity, multiple gestation, hydrops fetalis, and hydatidiform mole. Demographic and medical factors associated with an increased risk include elevated prepregnancy or early pregnancy blood pressure, prepregnancy adiposity, older age, family history, African-American ethnicity and preexisting medical conditions (e.g., hypertension or diabetes). Each of these risk factors also increases risk of remote cardiovascular disease. This is consistent with the increased risk of cardiovascular disease in women with a history of preeclampsia, greatest when the disease recurs or presents in early gestation.