Maternal prepregnancy body mass index and risk of bronchopulmonary dysplasia

BACKGROUND: We examined the relationship between women's prepregnancy BMI and development of bronchopulmonary dysplasia (BPD) in their preterm offspring, hypothesizing that obesity-associated inflammation may increase risk. METHODS: We studied infants born in California between 2007 and 2011, using linked data from California Perinatal Quality Care Collaborative neonatal intensive care units, hospital discharge, and vital statistics. We included infants with birthweight <1,500 g or gestational age at birth of 2229 weeks. BPD was defined as continuous supplemental oxygen use at 36 weeks' postmenstrual age. RESULTS: Among 12,621 infants, 4,078 (32%) had BPD. After adjustment for maternal race/ethnicity, age, education, payer source, and infant sex, BMI status underweight I (BMI <16.9, odds ratio (OR) 1.7, 95% confidence interval (CI) 1.3-2.1) and obesity III (BMI >= 40.0, OR 1.3, 95% CI 1.0-1.6) were associated with an increased risk of BPD. When considering maternal BMI as a continuous variable, a nonlinear association with BPD was observed for male infants and infants delivered at 25-29 weeks of gestational age, but not for other subgroups. CONCLUSION: Both high and low maternal BMI were associated with increased BPD risk. These findings support the notion that BPD is a multi-factorial disease that may sometimes have its origins in utero and be influenced by maternal inflammation.