It has been shown that milk derived from mothers with term infants is not optimal for premature babies. There is also concern about the effect of heat sterilizing breast milk. At Baragwanath Hospital, the majority of mothers remain with and care for their premature babies. Over many years, pooled pasteurized breast milk has been fed to these babies before direct breast feeding is instituted. A study was done to compare feeding pooled pasteurized breast milk and untreated own mother's milk to very low birth weight babies. There was a significantly more rapid weight gain both in terms of regaining birth weight and, from this point, to reaching a weight of 1,800 g when using untreated own mother's milk. This occurred in spite of the fact that there was little difference, especially in terms of energy content, between the two types of breast milk. This was due to the fact that the pooled pasteurized milk was also largely obtained from mothers of premature babies. It is suggested from our data that slower weight gain in the group receiving the pooled pasteurized milk could be due to the pasteurization, which probably destroys heat-labile milk lipase.
PIP: Researchers in South Africa conducted a randomized controlled clinical trial to compare weight gain in 68 very low birth weight neonates (1000-1500 g) fed either pooled pasteurized breast milk or untreated own mother's milk. At 96 hours, the neonates entered the trial with 3 hourly gavage feeds of 90-100 ml/kg/day and were increased in increments of 15 ml/kg/day, as tolerated, to a maximum feed of 200 ml/kg/day. When an infant's weight increased to 1500-1600 kg, bottle feeding began, if the infant could suck. Once the infant weighed 1800 kg, he dropped out of the trial and began to breast feed. Beginning with the 10th day of life, all infants received iron, ascorbic acid, and vitamin D. In addition, nurses injected all neonates with vitamin K at birth. At 5 days, no differences existed in energy content or protein and fat concentration of pool 1 milk (from mothers with neonates in the special care wards where babies were still gavage fed) and own mother's milk. Pool 1 milk did have significantly more lactose than own mother's milk (p=.006), however. At 19 days, own mother's milk had significantly more fat than pool 1 milk (p=.04). At 33 days, pool 2 milk (from mothers with low birth weight neonates in the common ward) contained significantly more lactose than own mother's milk (p=.009). There were no significant differences between the 2 groups, however, in energy, sodium and potassium contents. Those infants fed own mother's milk gained weight more quickly than those who had pooled pasteurized milk (mean weight gain=16 g/day). Further, infants on own mother's milk regained their birth weight sooner, reached 1800 g sooner, and had a faster growth rate than those on pooled pasteurized milk (p.0001). The researchers believe pasteurization accounts for the difference in weight gain by destroying milk lipases which enhance fat absorption. Even though serum vitamin E values were similar on entry to the trial in both groups, they increased significantly for the group fed own mother's milk at 19 and 33 days (p.0001 and p=.006 respectively).