Severe hypertension in pregnancy

Abstract

Severe hypertension in pregnancy is defined as a sustained systolic blood pressure of 160 mmHg or over or diastolic blood pressure of 110 mmHg or over and should be assessed in hospital. Severe hypertension before 20 weeks' gestation is rare and usually due to chronic hypertension; assessment for target organ damage and exclusion of secondary hypertension are warranted. The most common cause of severe hypertension in pregnancy is pre-eclampsia, which presents after 20 weeks' gestation. This warrants more rapid control of blood pressure due to the risk of haemorrhagic stroke, and intravenous antihypertensive agents may be required. Treatment is determined by licensing, availability and clinician experience, with no high-level evidence to guide prescribing. Labetalol is the agent most commonly used, both orally and intravenously, in pregnancy in the UK. Severe hypertension is a risk factor for sustained hypertension after pregnancy. Hypertension in pregnancy is associated with increased cardiovascular risk.