Nutritional balance studies of VLBW infants fed their mothers' milk fortified with a liquid human milk fortifier.

This article reports the results of a study designed to compare human milk fortified with a liquid human milk fortifier to a preterm infant formula by analyzing the metabolic balances of certain nutrients when these milks are fed to premature infants. Ten very low birth weight (VLBW) infants were studied during 4-day equilibration periods, then 4-day metabolic balances of N, fat, Ca and P, while each consumed a 1:1 mixture of a pool of its own mother's milk and the liquid human milk fortifier (HM/LF). For comparison, another 10 VLBW infants were studied in similar fashion while consuming the preterm infant formula (PF). Percent nitrogen retentions were 77 +/- 4% (+SD) and 79 +/- 4%, and fat absorptions were 94 +/- 7% and 92 +/- 5% in the HM/LF and PF groups, respectively, and did not differ between the groups. Calcium retention was 86 +/- 21 mg/kg/day (51 +/- 12%) in the HM/LF group and 104 +/- 43 mg/kg/day (45 +/- 19%) in the PF group. The percent Ca retentions did not differ. Phosphorus retentions were 56 +/- 7 mg/kg/day (67 +/- 9%) and 77 +/- 18 mg/kg/day (61 +/- 14%) in the HM/LF and PF groups, respectively. Increases in weight, length, and occipitofrontal circumference (OFC) were similar and normal in both groups. We conclude that VLBW infants fed the HM/LF, mixed 1:1 with their mothers' milk, had rates of absorption and retention of Ca, P, N, and fat similar to rates found in the concurrent study of VLBW infants fed a commercially available PF.