Human milk feeding and physical growth in very low-birth-weight infants: a multicenter study

Area of Science:

• Neonatal nutrition and growth
• Human milk utilization in Neonatal Intensive Care Units (NICUs)

Background:

• Human milk is recommended for preterm infants, but the impact of maternal versus donor milk on growth requires further investigation.
• Understanding growth trajectories in extremely preterm infants is crucial for optimizing nutritional strategies.

Purpose of the Study:

• To quantify the association between human milk feeding (maternal and donor) and in-hospital growth in preterm infants.
• To compare growth outcomes based on the proportion of donor milk consumed.

Main Methods:

• A cohort of 1429 infants born before 33 weeks gestation and weighing less than 1500g was studied across 9 NICUs.
• Linear mixed models were used to assess the relationship between the percentage of days fed human milk (any, maternal, or donor) and discharge z-scores for weight, length, and head circumference.
• Analyses adjusted for birth size and other relevant covariates.

Main Results:

• Overall human milk feeding (maternal or donor) was not significantly associated with in-hospital growth outcomes.
• Infants receiving donor milk on 50% or more of feeding days exhibited significantly less favorable growth (weight, length, head z-scores) compared to those receiving donor milk on less than 50% of days.
• Specific z-score differences were noted for weight (-1.1 vs. -0.7), length (-1.5 vs. -1.1), and head circumference (-1.0 vs. -0.3) between the high and low donor milk groups.

Conclusions:

• While overall human milk feeding did not impair growth, a high proportion of donor milk intake was associated with poorer growth outcomes in extremely preterm infants.
• Fortified human milk did not demonstrate impaired growth compared to preterm formula, suggesting fortification strategies may mitigate potential negative impacts.