Improved Growth Velocity Using a New Liquid Human Milk Fortifier in Very Low Birth Weight Infants: A Multicenter, Retrospective Study

This study aimed to compare growth outcomes and tolerance among very low birth weight (VLBW) infants receiving a new, liquid human milk fortifier (LHMF-NEW) or a human milk fortifier-acidified liquid (HMF-AL).Retrospective, multicenter study of 515 VLBW infants in three regional neonatal intensive care units. The primary objective was to compare growth velocity (g/kg/d) during fortification between groups by repeated measures regression. Secondary outcomes of interest were feeding tolerance and the incidence of late-onset sepsis, necrotizing enterocolitis, and metabolic acidosis. Student's <i>t</i>, analysis of variance, Wilcoxon, and Kruskal-Wallis tests were used for numeric variables, or chi-squared and Fisher's exact test for categorical variables.No demographic differences were identified between the groups (HMF-AL, <i>n</i> = 242; LHMF-NEW, <i>n</i> = 273). Growth velocity during fortification was significantly higher in the group receiving LHMF-NEW, despite relatively similar total fluid, calorie, or protein intake (<i>p</i> = 0.001). Feeding intolerance was comparable between fortifiers. Necrotizing enterocolitis and late-onset sepsis did not differ between groups and metabolic acidosis was diagnosed less frequently with the LHMF-NEW. Anthropometric measures at discharge and length of stay were comparable.Infants receiving human milk fortified with the LHMF-NEW had faster growth velocity during fortification, similar tolerance, and less metabolic acidosis compared with an earlier cohort of infants who received human milk fortified with an HMF-AL. · Among VLBW infants, using an LHMF-NEW resulted in a faster growth velocity in weight during several weeks of fortification than using the previous HMF-AL.. · The incidence of feeding intolerance (stopping feeds >8 hour) in any given week of fortification was low and not different between groups. Also, late-onset sepsis and necrotizing enterocolitis were uncommon with no differences between groups, whereas the incidence of metabolic acidosis was lower in infants receiving the LHMF-NEW.. · No differences in length of stay or anthropometrics at discharge were identified..