Induction of Labor Versus Expectant Monitoring for Gestational Hypertension or Mild Preeclampsia After 36 Weeks' Gestation (HYPITAT): A Multicentre, Open-Label Randomized Controlled Trial EDITORIAL COMMENT

Although induction of labor in pregnant women at term with gestational hypertension or mild preeclampsia is already recommended and practiced in the United States and other developed countries, no randomized clinical trials have been carried out comparing induction of labor versus expectant monitoring. This multicenter, parallel, randomized, unblinded controlled trial compared the effect of labor induction or expectant management on maternal morbidity in singleton women with gestational hypertension or mild preeclampsia at term. A total of 776 women were randomized to undergo induction of labor (n = 377) or expectant monitoring (n = 379). The study was conducted between 2005 and 2008 at 38 hospitals in the Netherlands. The primary outcome measure was a composite of adverse maternal outcomes: maternal mortality, maternal morbidity (eclampsia, HELLP syndrome, pulmonary edema, thromboembolic disease, or placental abruption), progression to severe disease or proteinuria, and major postpartum hemorrhage (blood loss of more than 1000 mL within 24 hour of delivery). Data were analyzed according to an intention-to-treat basis. The composite adverse primary outcome occurred in fewer women who were induced compared to those receiving expectant monitoring (31% [117/377] vs. 44% [166/379]; the relative risk was 0.71, with a 95% confidence interval of 0.59-0.86, P < 0.0001). No fetal or neonatal deaths or cases of eclampsia or placental abruption occurred in either group. The investigators conclude from these findings that women with mild hypertensive disease beyond 37 weeks' gestation should be advised to undergo induction.