Meeting the nutritional needs of the low-birth-weight infant.

Delivering adequate amounts of nutrients to premature infants at all times is challenging because the infant's immature gastrointestinal tract is initially unable to accept feedings, necessitating the use of parenteral nutrition. In the past, inadequate amounts of nutrients have commonly been given to premature infants because the administration of nutrients was thought to be hazardous. Inadequate nutrient intakes have resulted in widespread postnatal growth restriction. Now that it is known that postnatal growth restriction is associated with poor neurocognitive development, efforts are made to increase nutrient intakes. In this review, nutrient requirements of premature infants that have been determined by the factorial and empirical methods are reviewed. Current good practices regarding parenteral nutrition are discussed, as are guidelines for the introduction and advancement of enteral feedings. Because of its trophic effects on the gastrointestinal tract and its anti-infectious effects, human milk is strongly preferred as the early feeding of choice for premature infants. Human milk also protects infants against necrotizing enterocolitis. Once full feeding is achieved, the challenge is to provide nutrients in amounts that support the infant's growth like that of the fetus. In the case of the infant fed his/her mother's milk or banked donor milk, nutrient fortification is necessary and is generally practiced. However, adequate intakes of protein are seldom achieved with routine fortification and methods of providing additional fortification are discussed.