OS011. Management of late preterm pregnancy complicated by mildpreeclampsia: A prospective randomized trial

Abstract

In the absence of properly undertaken prospective randomized clinical trials, the optimal management of late preterm mild preeclampsia for best maternal and perinatal outcomes remains unclear for obstetricians worldwide. We desired to determine if immediate or expectant management of the late preterm mother presenting with mild preeclampsia was more beneficial to her without compromise to her newborn. This prospective randomized clinical trial of immediate versus expectant delivery for patients presenting with mild preeclampsia between the late preterm period of 34-0/7 to 36-6/7weeks gestation was undertaken using CONSORT guidelines. Patients were randomized to immediate delivery via induction of labor or cesarean delivery or inpatient expectant management with delivery at 37-0/7weeks gestation or earlier at onset of labor or progression to severe preeclampsia. The primary outcome was progression to severe preeclampsia; secondary outcomes were neonatal morbidity and mortality. Data were analyzed by appropriate tests for continuous or categorical outcomes with differences considered significant if p<0.05. One hundred and sixty nine patients during 2002-2008 satisfied and sustained protocol criteria in the immediate delivery (n=94) or inpatient expectant management (n=75) arms of the study. A third (33%) of expectantly managed patients developed severe preeclampsia during significantly longer hospitalization versus 3% in the immediately delivered patients (p=0.001). Cesarean delivery rates were similar. No significant neonatal morbidity differences were observed between groups; there were no maternal or neonatal deaths. The study was stopped in 2008 at 74% of the enrollment target when hospital policy changed to discourage inpatient hospitalization for uncomplicated mild preterm preeclampsia and in view of growing national concern for increased late preterm/early term neonatal morbidity and cost of care. Proceeding to delivery of the late preterm (⩾34weeks gestation) patient with mild preeclampsia lessens maternal risk without significantly increasing neonatal risk.