Chronic hypertension in pregnancy is defined as high blood pressure that is present before pregnancy or before 20 weeks of pregnancy. It is a common medical problem that can put both the mother and baby at risk for complications during and after delivery. Chronic hypertension can also lead to preeclampsia, a condition that can cause damage to organs and other serious complications.

According to the American College of Obstetricians and Gynecologists (ACOG), pregnant women with chronic hypertension should start antihypertensive medication when their blood pressure reaches 160 mm Hg systolic or 110 mm Hg diastolic. However, treatment of hypertension during pregnancy is challenging because of the uncertain risks of mild hypertension and potential uteroplacental insufficiency with overtreatment.

It is important to note that up to 1.5% of pregnant women have chronic hypertension, and the rates of chronic hypertension are increasing and are predicted to continue because of obesity and older maternal age. Women with chronic hypertension in pregnancy should be monitored for the development of worsening.