Necrotizing Enterocolitis and Growth in Preterm Infants Fed Predominantly Maternal Milk, Pasteurized Donor Milk, or Preterm Formula: A Retrospective Study

Abstract

Objective To evaluate the association between necrotizing enterocolitis (NEC), growth, and feeding. Methods This is a retrospective study of 551 infants (birth weight ≤ 1,500 g, ≤32 weeks' gestation). NEC, Bell's stage ≥ 2, was confirmed by independent review of sentinel radiographs. Feeding type was defined as ≥ 50% maternal milk (MM), pasteurized donor human milk (PDHM), or preterm formula (PF). Demographic and clinical characteristics including growth were compared between the three groups. Multivariable regression analysis was performed to control variables that differed in bivariate analysis. Results PDHM and PF mothers were more likely to be African-American, be enrolled in Medicaid, and have chorioamnionitis. PF mothers received antenatal steroids less frequently. NEC rates were different by feeding group (MM: 5.3%; PHDM: 4.3%; PF: 11.4%; p = 0.04). Adjusting for group differences, lower gestational age (adjusted odds ratio [aOR]: 0.85; 95% confidence interval [CI]: 0.74-0.97; p = 0.02], and PF (aOR: 2.53; 95% CI: 1.15-5.53; p = 0.02] were associated with NEC. There were no differences in other health outcomes or growth at hospital discharge. Conclusion MM and PDHM feedings, given until 34 weeks postmenstrual age, were associated with lower rates of NEC in very low birth weight infants without interfering with growth.