A comparative study of a premature infant formula and preterm breast milk for low birthweight infants

Although the unique composition of preterm milk (PTM) has led to its increasing use in feeding of low birthweight (LBW) infants, controversy exists as to whether such milk adequately meets their requirements. This study compares the clinical tolerance and anthropometric, biochemical and haematological parameters of LBW infants fed exclusively with their own mother's PTM, a premature infant formula (Alprem; Nestlé Australia) and a mixture of PTM and Alprem. Of 90 enrolled LBW infants (1000-1750 g birthweight), 78 completed the feeding trial for a mean duration of 42 days. Twenty-eight babies were fed Alprem (Group A), 31 received a mixture of Alprem and PTM (Group B) and 18 received PTM (Group C). Babies in Groups A and B were smaller, less mature and more asphyxiated at birth than those in Group C. Weight gain from full enteral feeding was greater in Group A (18.1 g/kg per day) and Group B (17.6 g/kg per day) than in Group C (13.0 g/kg per day). Throughout the trial, weight gain in Groups A and B exceeded predicted intra-uterine growth rates, whereas that for Group C approximated the predicted intra-uterine growth rates. Growth rates of length and head circumference were also greatest in the Alprem-fed babies. Infants receiving PTM were supplemented with calcium, sodium, vitamins and energy, whereas the only three infants requiring mineral supplementation in the Alprem group were those receiving Frusemide therapy for chronic lung disease. Lower serum concentrations of phosphorus, iron, albumin and urea, and higher zinc and alkaline phosphatase concentrations were found in infants receiving PTM (P<0.05). Overall both PTM and Alprem were well tolerated with the four cases of necrotizing enterocolitis and five cases of transient gastrointestinal intolerance distributed equally among the groups. Alprem is a satisfactory alternative to PTM for the feeding of LBW infants as it provides adequate nutrition and supports a growth rate in excess of that in utero without stressing the infant's metabolic or excretory systems.