Human milk feeding, fortification initiation, and clinical outcomes in neonates with critical congenital heart disease: A multi-institutional study

Background Neonates with critical congenital heart disease (CCHD) are vulnerable to feeding-related complications including necrotizing enterocolitis (NEC). Human milk and direct breastfeeding (BF) may offer protection, but multisite evidence is limited. We aimed to determine relationships between the proportion of human milk received (ie, human milk percentage) or BF frequency during the neonatal period and NEC, sepsis, infectious complications, or length of stay (LOS). We also determined whether bovine-derived fortification or formula initiation was associated with NEC. Methods This retrospective study included neonates from 25 US pediatric centers who underwent surgery with cardiopulmonary bypass. Outcomes were NEC (modified Bell's Stages II-III), sepsis, infection, and LOS. Disease risk score case-control matching and energy balancing weighted regression balanced multiple relevant covariates. Results Among 822 neonates, the percentage of human milk received during the neonatal period was not associated with NEC, sepsis or infection. Initiation of fortification or formula was associated with 3-fold higher odds of developing NEC within 5 days (OR:3.10, 95%CI:1.10-8.12, p=0.025). In energy balancing weighted regression models, higher neonatal human milk percentage and more frequent BF were strongly associated with shorter LOS: 100% versus 0% human milk with 9.33 days shorter (4.47-14.19, p<0.001); each additional BF session with 0.48 days shorter (0.31-0.65, p<0.001). Conclusions In this multisite cohort, fortification or formula initiation was associated with increased odds of NEC; and neonatal human milk percentage and BF with shorter LOS. Given limited evidence to guide practice, caution in introducing bovine-derived formula for high-risk infants with CCHD may be warranted.