641 Fetal growth restriction and risk of intrapartum cesarean among women with early onset preeclampsia

Abstract

Early onset preeclampsia (PE) is associated with increased maternal and neonatal morbidity, including fetal growth restriction (FGR) and higher rates of cesarean delivery (CD). While the optimal route of delivery is unknown, the higher rate of CD is due to perceived failure of induction and need for expedited delivery for maternal benefit. Therefore, we aimed to compare intrapartum CD rates in women with early onset PE with and without FGR. Retrospective chart review of women with early onset PE, defined as PE with severe features that developed < 34 weeks of gestation, delivering at a single tertiary care center between 2011-2020. Women were excluded if they did not undergo trial of labor, had fetal demise or fetal anomaly. FGR was defined as estimated fetal weight or abdominal circumference less than the tenth percentile for gestational age by Hadlock calculator. Our primary outcome was intrapartum CD. Secondary outcomes included indications for CD, a composite of maternal and neonatal outcomes. Results were adjusted for tobacco use and body mass index (BMI) at delivery. Of 261 patients identified, 131 (50%) patients had viable, non-anomalous fetus and underwent a trial of labor. Patients with FGR (n=33, 25.2%) had lower body mass index at delivery (29.3 kg/m2 vs 33.6 kg/m2; P=<0.01), and were more likely to use tobacco (21.2% vs 7.1%, P=0.03), have a fetal indication for delivery (27.3 vs 10.2%, P=0.02), and lower neonatal birthweight (1162g vs 1638g, P=<0.01) compared with patients without FGR. (Table 1) The overall rate of CD was 55% in the cohort. It was higher in patients with FGR (67%) compared with those without FGR (49%), but the difference did not reach statistical significance (aOR 1.74, 95% CI 0.73-4.11). There were no differences in composite of maternal or neonatal adverse outcomes. (Table 2) Women diagnosed with early onset PE and undergo trial of labor have more than 50% rate of CD. However, FGR is not associated with higher risk for CD and should not automatically exclude women from being offered a trial of labor.View Large Image Figure ViewerDownload Hi-res image Download (PPT)