The Treatment of Hypertension Associated With Severe Preeclampsia (PE). A Trial of Urapidil Versus Nicardipine

The objective of this study is to demonstrate that urapidil is not inferior to nicardipine for the treatment of hypertension associated with preeclampsia (PE) and that it is better tolerated. * efficacy endpoint : mean arterial blood pressure corrected to 100-120 mmHg after 120 min of study drug administration. * safety endpoints : clinical and biological observation for any side effect. All infants will be observed in the neonatology unit (during 48h). Pharmacokinetic study included to study : * transplacental transfer, * transfer in breast milk, * and neonatal elimination (premature babies of mothers treated with urapidil (less than 33 WG))