Maternal obesity: significance on the preterm neonate.

Background: What is known of neonatal outcomes associated with maternal obesity is limited. The impact on the preterm neonate, delivery room (DR) course and need for neonatal intensive care unit (NICU) admission has not been well established.

Methods: A review was done of our 17 county perinatal regions from the New York State Perinatal Data System database over the 3-year period of 1 January 2010-31 December 2012 for mother/baby dyad information for all live births 34-36 6/7 weeks' gestation. The National Institutes of Health body mass index (BMI) classification was used for maternal BMI with the category definitions of underweight, normal, overweight, obese Level I, obese Level II, and obese Level III.

Results: Information was obtained on 2155 women. In this group, 29% had obese BMIs. The incidence of pre-pregnancy diabetes mellitus (DM), DM during gestation and cesarean delivery (CD) in obese mothers was significantly different from normal weight mothers, P<0.001. More infants of Level III mothers required DR resuscitation when compared with infants of normal BMI mothers, 36 vs 16%, P <0.001. The need for assisted ventilation beyond 6 h of age and need for NICU admission was more likely in infants of Level III mothers, P<0.001. Women in all of the obese subgroups had preterm infants with increased birth weights (BWs) compared with preterm infants of normal weight mothers, P<0.001.

Discussion: Late preterm infants born to obese mothers are more likely to be delivered by cesarean section and have larger BWs. We found that infants born to obese Level III mothers are much more likely to require assisted ventilation in the DR and NICU admission.