880 National neonatal outcomes in pregnancies complicated by superobesity

Abstract

Superobesity (pre-pregnancy body mass index, or BMI, >=50 kg/m2) is increasingly prevalent in the United States. Perinatal outcome data on superobesity is limited. This study sought to determine whether superobesity is associated with adverse neonatal and maternal outcomes. Using the 2016-2018 National Vital Statistics System Birth Data, we compared women with superobesity to those with morbid obesity (BMI 40-49.9), obesity (BMI 30-39.9), overweight (BMI 25-29.9) and normal weight (BMI 20-24.9). Risk of poor neonatal outcomes including low Apgar scores, neonatal seizures, neonatal intensive care unit (NICU) admission, immediate ventilation, and preterm delivery was stratified by obesity class. Risk was evaluated by log linear regression modeling with the primary exposure of obesity, adjusting for age, race, insurance status, diabetes, hypertension, mode of delivery, chorioamnionitis, fetal anomalies and preterm delivery with adjusted risk ratios (aRR) as measures of association. We identified 11.2 million delivery hospitalizations, 3.2% (n=360,742) linked to patients with superobesity. In adjusted analyses, including for mode of delivery, neonates born to patients with superobesity were at significantly higher risk for Apgar score <5 at 5 (aRR 1.74, 95% CI 1.69, 1.79) and 10 minutes (aRR 1.30, 95% CI 1.24, 1.36), neonatal seizures (aRR 1.41, 95% CI 1.20, 1.66), NICU admission (aRR 1.19, 95% CI 1.18, 1.20), and immediate ventilation (aRR 1.12, 95% CI 1.11, 1.14) compared to normal BMI (Figure). In addition, mothers with superobesity were at higher risk for preterm delivery (<28 weeks: aRR 2.62, 95% CI 2.54, 2.71; <34 weeks: aRR 1.74, 95% CI 1.71, 1.77; <37 weeks: aRR 1.35, 95% CI 1.34, 1.36) compared to normal BMI. The effect of BMI obesity class was ‘dose dependent’ (Table). Women with superobesity are at higher risk of poor perinatal outcomes compared to women with lower BMI. These findings confirm the significant risks of superobesity and underscore the importance of pre-conceptional health optimization.View Large Image Figure ViewerDownload Hi-res image Download (PPT)