How to manage hypertension in pregnancy effectively

Abstract

The hypertensive disorders of pregnancy (HDP) are a leading cause of maternal mortality and morbidity in both well and under-resourced settings. Maternal, fetal, and neonatal complications of the HDP are concentrated among, but not limited to, women with pre-eclampsia. Pre-eclampsia is a systemic disorder of endothelial cell dysfunction and as such, blood pressure (BP) treatment is but one aspect of its management. The most appropriate BP threshold and goal of antihypertensive treatment are controversial. Variation between international guidelines has more to do with differences in opinion rather than differences in published data. For women with severe hypertension [defined as a sustained systolic BP (sBP) of ≥160 mmHg and/or a diastolic BP (dBP) of ≥110 mmHg], there is consensus that antihypertensive therapy should be given to lower the maternal risk of central nervous system complications. The bulk of the evidence relates to parenteral hydralazine and labetalol, or to oral calcium channel blockers such as nifedipine capsules. There is, however, no consensus regarding management of non-severe hypertension (defined as a sBP of 140-159 mmHg or a dBP of 90-109 mmHg), because the relevant randomized trials have been underpowered to define the maternal and perinatal benefits and risks. Although antihypertensive therapy may decrease the occurrence of BP values of 160-170/100-110 mmHg, therapy may also impair fetal growth. The potential benefits and risks do not seem to be associated with any particular drug or drug class. Oral labetalol and methyldopa are used most commonly, but many different β-adrenoceptor blockers and calcium channel blockers have been studied in clinical trials.