302: Placental histopathological lesions in correlation with neonatal outcome in preeclampsia with and without severe features

Abstract

We aimed to compare pregnancy outcome and placental histopathology in women with preeclampsia with and without severe features. Labor, maternal characteristics, neonatal outcome, and placental histopathology reports of pregnancies complicated by preeclampsia from 2008-2016 in a single university hospital were reviewed. Results were compared between those with and without severe features according to the current ACOG guidelines. Placental lesions were classified to maternal vascular malperfusion lesions, fetal vascular lesions consistent with fetal thrombo-occlusive disease, and maternal/fetal inflammatory responses. Small for gestational age (SGA) was defined as neonatal birth-weight ≤ 10th %. Composite adverse neonatal outcome was defined as one or more of the following early complications: sepsis, blood transfusion, phototherapy, respiratory morbidity, cerebral morbidity, NEC, or death. Regression analysis was used to identify independent associations with adverse neonatal outcome. The preeclampsia with severe features group (n=284) was characterized by a lower gestational age at delivery (35.1±3.7 vs. 36.7±2.3 wks, p<0.001), and a higher rate of cesarean deliveries (p<0.001) as compared to the preeclampsia without severe features group (n=151). Placental weight <10th percentile and lesions associated with maternal malperfusion were significantly more common in the preeclampsia with severe features group as compared to the preeclampsia without severe features (p<0.001 for both). The rate of fetal vascular supply lesions or inflammatory lesions did not differ between the groups. Additionally, the preeclampsia with severe features group had higher rates of SGA (p=0.016), NICU admission (p=0.014), and composite adverse neonatal outcome (p=0.002). Using regression analysis adverse neonatal outcome was independently associated with gestational age (aOR= 0.54, 95% CI 0.49-0.68), SGA (aOR=1.75, 95% CI=1.15-3.59), severe preeclampsia (aOR=1.8, 95%CI = 1.13-3.54) and placental maternal malperfusion lesions (aOR=2.13, 95% CI=1.05-4.39). Preeclampsia with severe features is associated with a higher rate of placental lesions and adverse neonatal outcome. The adverse neonatal outcome is associated with placental malperfusion independent of background confounders.