Immediate fortification of human milk with a bovine milk-derived human milk fortifier in very low birth weight infants: a randomized clinical trial.

OBJECTIVE: Double-blind randomized control trial of early addition of a bovine milk-derived human milk fortifier (HMF) in very low birth weight (VLBW) infants (NCT05228535). METHODS: VLBW infants were randomized to receive bovine milk-derived HMF with first feedings or delayed fortification at 80 ml/kg/day. Anthropometrics were assessed weekly through 36 weeks postmenstrual age (PMA). Unadjusted and adjusted (race, gender, gestational age, and birth weight) differences between study arms were examined using two-sample t-test and ANCOVA, respectively. RESULTS: Fifty-two VLBW infants (57% female, 60% Black) were enrolled. Baseline demographics did not differ between groups. Weight velocity at DOL 28 did not differ between study arms. Secondary outcomes including NPO occurrence, incidence of metabolic acidosis, NEC, retinopathy, or late-onset sepsis did not differ between groups. CONCLUSION: Immediate fortification of enteral feedings with a bovine milk-derived HMF appears safe and well-tolerated although no clear growth benefit could be established.

Hypothyroxinemia and weight velocity in preterm infants.

OBJECTIVES: Hypothyroxinemia of prematurity (HOP) is characterized by low free thyroxine (FT4) associated with low or normal thyroid stimulating hormone (TSH). The objective of this study is to define FT4 and TSH values in very preterm infants (<32 weeks postmenstrual age, PMA) and correlate hypothyroxinemia and levothyroxine treatment with growth velocity at 28 days and 36 weeks PMA. METHODS: Preterm neonates <32 weeks PMA admitted to the regional neonatal intensive care unit (NICU) at the Children's Hospital of Georgia (USA) between January 2010 and July 2022 were routinely screened for hypothyroxinemia. FT4 and TSH values were obtained on 589 eligible neonates between day of life (DOL) 4 and 14. Growth velocity (g/kg/day) from DOL 14 to DOL 28 and 36-weeks PMA were calculated for each neonate and potential explanatory variables (PMA, sex, and race) were incorporated into multivariate regression models to identify associations between HOP and growth velocity. RESULTS: In 589 preterm infants, PMA at birth was strongly associated inversely with FT4 (R=0.5845) and modestly with TSH (R=0.2740). Both FT4 and gestational age, but not TSH or levothyroxine treatment, were associated with growth velocity at 28 days of life and at 36 weeks PMA. CONCLUSIONS: We provide a large data set for identifying FT4 and TSH measurements and identify hypothyroxinemia of prematurity as a potential mediator of slow postnatal growth in very preterm infants.