sFlt1/PlGF and Planned Delivery to Prevent Preeclampsia at Term.

* Preeclampsia (PE) affects \~5% of pregnancies. Although improved obstetrical care has significantly diminished associated maternal mortality, PE remains a leading cause of maternal morbidity and mortality in the world. * Term PE accounts for 70% of all PE and a large proportion of maternal-fetal morbidity related with this condition. Prediction and prevention of term PE remains unsolved. * Previously proposed approaches are based on combined screening and/or prophylactic drugs, but these policies are unlikely to be implementable in many world settings. * Recent evidence shows that sFlt1-PlGF ratio at 35-37w predicts term PE with 80% detection rate. * Likewise, recent studies demonstrate that induction of labor (IOL) from 37w is safe. * The investigators hypothesize that a single-step universal screening for term PE based on sFlt1/PlGF ratio at 35-37w followed by IOL from 37w would reduce the prevalence of term PE without increasing cesarean section rates or adverse neonatal outcomes. * The investigators propose a randomized clinical trial to evaluate the impact of a screening of term PE with sFlt-1/PlGF ratio in asymptomatic nulliparous women at 35-37w. Women will be assigned to revealed (sFlt-1/PlGF known to clinicians) versus concealed (unknown) arms. A cutoff of \>90th centile will be used to define high risk of PE and offer IOL from 37w. * If successful, the results of this trial will provide evidence to support a simple universal screening strategy reducing the prevalence of term PE, which could be applicable in most healthcare settings and have enormous implications on perinatal outcomes and public health policies worldwide.