ACOG section

Abstract
Chronic hypertension occurs in up to 5% of pregnant women; rates vary according to the population studied and the criteria used for confirming the diagnosis (1,2). This complication may result in significant maternal, fetal and neonatal morbidity and mortality. There has been confusion over the terminology and criteria used to diagnose this complication, as well as the benefit and potential harm of treatment during pregnancy. The purpose of this document is to review the effects of chronic hypertension on pregnancy, to clarify the terminology and criteria used to define and diagnose it during pregnancy, and to review the available evidence for treatment options.