Author Affiliation: Department of Obstetrics and Gynecology, University of Cincinnati College of Medicine, Cincinnati, Ohio.
In pregnant women, chronic hypertension is defined as elevated blood pressure that is present and documented before pregnancy.1 In women whose prepregnancy blood pressure is unknown, the diagnosis is based on the presence of sustained hypertension before 20 weeks of gestation. Chronic hypertension is a relatively common disorder occurring in approximately 1% to 5% of pregnant women.1 Estimating a prevalence of chronic hypertension during pregnancy of 3%, there are at least 120 000 pregnant women with chronic hypertension (3% of 4 million pregnancies) per year in the United States, a rate expected to increase in the United States with the obesity epidemic and as age at childbearing increases.1
Sibai BM. Caring for Women With Hypertension in Pregnancy. JAMA. 2007;298(13):1566–1568. doi:10.1001/jama.298.13.1566