The calorie intake and weight gain of low birth weight infants fed on fresh breast milk or a special formula milk.

The calorie intake and weight gain of 24 low birth weight (LBW) infants, less than 33 weeks gestation and less than 1500 g birth weight, was studied prospectively. Fourteen infants were fed on a commercially available LBW formula milk and ten were fed on their own mother's fresh unpasteurised expressed breast milk (EBM). The difference between the two feeding groups in the intake of milk and calories was not significant, but from the third week onwards those fed on the LBW formula gained weight faster. The mean (+/- SEM) weight increments for weeks 3-6 (inclusive) for LBW formula and EBM fed infants was 189.3 (+/- 7.9) and 139.6 (+/- 11.1) g/wk respectively (P less than 0.001). The LBW formula was well tolerated and is a suitable feed for LBW infants. However some babies thrived well on fresh EBM and so we are continuing to encourage mothers who wish, to breast feed their own preterm infants. When such infants fail to thrive it is appropriate to supplement with a LBW formula.