Objectives: Quantify associations of human milk feeding with in-hospital growth and examine differences by human milk type (maternal or donor).
Study design: We included infants born <33 weeks’ gestation and <1500 g from 9 Neonatal Intensive Care Units (n = 1429). We estimated associations of percent of visit days fed any human milk (maternal or donor) and percent of days fed donor milk with weight, length, and head z-scores at discharge or transfer using a linear mixed model, adjusting for birth size and other covariates.
Results: Any human milk feeding was not associated with growth outcomes. Infants fed donor milk on ≥50% of days had less favorable growth vs. those fed <50% [z-scores-weight: -1.1 vs. -0.7 (p = 0.04); length: -1.5 vs. -1.1 (p = 0.04); head -1.0 vs. -0.3 (p < 0.01)].
Conclusions: Fortified human milk was not associated with impaired growth compared with preterm formula.