Post–Control of Hypertension in Pregnancy Study (CHIPS)
What Is the Optimal Strategy to Manage Hypertension During Pregnancy?
This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Hypertension in pregnancy remains a significant cause of maternal and neonatal morbidity and mortality. The structure of prenatal care with increasing frequency of visits near term is designed to identify generally asymptomatic women with hypertension or proteinuria and deliver them before the development of life-threatening hypertension. In the developed world, this strategy has been generally successful with marked reductions in the rates of maternal mortality and eclampsia. In low- and middle-income countries, where access and use of prenatal care are limited, maternal mortality and eclampsia remain commonplace.
Treatment of severe hypertension (systolic blood pressure [DB], ≥160 mm Hg; or diastolic BP, ≥110 mm Hg) is broadly recommended.1,2 The California Maternal Quality Care Collaborative mandates initiation of treatment of severe hypertension within 1 hour of confirmation as minimal requirement for standard process.3 In contrast, the American College of Obstetricians and Gynecologists (ACOG) Practice Bulletin on Hypertension in Pregnancy recommends withholding antihypertensive therapy for BPs <160/110 mm Hg (or 160/105 mm Hg for chronic hypertension).1 Current recommendations are largely based on committee opinions with particular concern on the effect of treatment on the fetus. Recommendations to manage BP expectantly at <160/110 mm Hg and then emergently at >160/110 mm Hg seem logically inconsistent.
The Control of Hypertension in Pregnancy Study (CHIPS) was a multicenter randomized, controlled trial of BP management in pregnancy.4 The trial was designed to evaluate what the authors described as tight control compared with less tight control. The trial was pragmatic in that pregnant women between 14 and 34 weeks of gestation with a diastolic BP of ≥90 mm Hg (≥85 mm Hg if on antihypertensive medication) were eligible without regard to classification of gestational or chronic hypertension; randomization was stratified to achieve a balance between groups. Seventy-five percent had chronic hypertension. Women with proteinuria, severe, uncontrolled hypertension, and comorbidities were …