High-proportion of human milkfeeding reduces necrotizing enterocolitis and feeding intolerance among very preterm infants

Background Very preterm infants (VPIs; gestational age 28–31⁺⁶ weeks) are highly susceptible to necrotizing enterocolitis (NEC) and feeding intolerance (FI) because of their gastrointestinal immaturity. Although breast milk contains protective bioactive components, the optimal proportion for clinical benefit remains undefined. The aim of this study was to evaluate the dose‒response effects of the proportion of breast milk on early growth and major complications associated with VPIs. Methods This retrospective study included 230 cases of VPIs admitted to a tertiary neonatal intensive care unit between July 2020 and December2021. On the basis of the proportion of human milk at full enteral feeding, the participants were divided into three groups: high-proportion human milk feeding group (breast milk > 50%, n = 75), low-proportion human milk feeding group (breast milk ≤ 50%, n = 76), and formula feeding group ( n = 79). Baseline characteristics, time to full enteral feeding, hospitalization duration, changes in growth velocity and incidence of major complications were compared among the three groups. Results No significant differences in baseline characteristics or the time to full enteral feeding, hospitalization duration, or growth velocity were detected among the three groups ( P > 0.05). Compared with formula feeding group, high-proportion human milk feeding group had significantly lower incidences of FI (2.67% vs. 15.19%) and NEC (2.68% vs. 13.92%) ( P < 0.05). No significant differences were detected in bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), intraventricular hemorrhage (IVH), patent ductus arteriosus (PDA), or sepsis ( P > 0.05). Conclusions High-proportion human milk feeding reduces FI and NEC risk in VPIs without compromising early growth velocity, time to full enteral feeding, or hospitalization duration. This recommendation is conditional on confirmation in larger, multicenter studies.These findings support prioritized human milk promotionfor this vulnerable population.