Formulation of preterm formula: What's in it, and why?

Human milk feeding of preterm infants reduces mortality and morbidity (in particular sepsis and necrotizing enterocolitis). When their own mother's milk is not available, and in the absence of donor milk, such fragile infants must be fed formula. In many instances, preterm infant formulas (PIFs) attempt to mimic the composition of human milk (the gold standard of infant feeding), but they must take into account as well the unique nutritional needs of the growing preterm infant, which are not identical to those of the healthy term infant. In this article we review the major characteristics of PIFs and try to evaluate the evidence and rationale behind their composition. A table comparing PIFs from several major manufacturers is presented for the convenience of the reader.