Early Human Milk Fortification in Infants Born Extremely Preterm

The goal of a new study was to investigate the effects of fortified human milk on the growth and development of extremely preterm infants born at 28 weeks of gestational age or younger. The primary concern was the cumulative protein and energy deficits that often occur in preterm infants when they are fed unfortified human milk during the first two weeks after birth.

The study employed a masked, randomized trial design involving infants who received either maternal or donor milk. From the second day of feeding, the infants were randomly assigned to one of two groups – the intervention group received a diet fortified with a human-based product, while the control group received a standard, unfortified diet. This feeding regimen continued until the day when a standard bovine-based fortifier was introduced. Caregivers were unaware of the group assignments. The primary outcome measure was the fat-free mass (FFM)-for-age z score at 36 weeks of postmenstrual age (PMA).

Overall, 150 infants born from 2020 to 2022 were included – with a mean birth weight of 795±250 grams and a median gestational age of 26 weeks. Unfortunately, 11 infants died during the observation period. The primary outcome was assessed in 105 infants (70%). The results indicated that FFM-for-age z scores did not show significant differences between the intervention and control groups. However, infants in the intervention group demonstrated higher length gain velocities from birth to 36 weeks PMA, suggesting improved linear growth. Moreover, declines in head circumference-for-age z scores from birth to 36 weeks’ PMA were less pronounced in the intervention group.

The findings suggested that fortifying human milk soon after birth in extremely preterm infants did not lead to a significant increase in FFM accretion at 36 weeks PMA. However, it did appear to enhance length gain velocity and mitigate declines in head circumference-for-age z scores during this critical developmental period. Further, early provision of fortified human milk within the first 96 hours after birth may have a positive impact on the growth and development of extremely preterm infants despite not significantly affecting FFM accretion at term-equivalent age.

Source: Salas AA, Gunawan E, Nguyen K, Reeves A, Argent V, Finck A, Carlo WA.Pediatrics. 2023 Sep 1;152(3):e2023061603.