Nutrition of the preterm infant

Abstract

Nutrition is of great importance for the preterm infant. It is not only essential for survival, but also makes provision for rapid development of many organs outside the uterus which process normally takes place in the third trimester of pregnancy. It is for future life essential that all factors that might influence the development are as optimal as possible, including nutrition. However, there might also be an upper limit to the intake of some ingredients in the neonatal period. The rate of growth of the preterm infant is five times higher compared to term infants and the breast of the mother delivering preterm might yet be ready to produce the optimal composition of milk. Preterm infants receiving mothers milk only are known to show a lower gain in weight and length than the so called reference fetus. It is therefore at least questionable if preterm human milk can be used to define the nutritional needs of the preterm infant. To define the optimal composition and amounts of nutrients for the preterm infant a factorial approach can be used. The estimated requirements are calculated from the calculated requirements for maintenance and growth. Though some studies have shown that the protein content of milk from mothers who delivered preterm can be higher in the first few weeks after birth compared to milk of term delivering mothers, soon after there is a rapid decline in protein content after which period the content is not different from the term delivered mother. Providing exclusively mothers own milk leads to suboptimal growth and insufficient accretion of minerals. The needs of the preterm infant in energy, protein, lipids, carbohydrates, minerals, pro- and prebiotics to provide optimal nutrition in the first days after birth are discussed in the paper. It is concluded that nowadays early, aggressive nutrition directly after premature birth with the immediate introduction of amino acids and rapid introduction of lipids is advised. Enteral feeding should be started very soon after birth, preferably on the first day of life and increased in the days thereafter. The first choise for enteral feeding is mothers own milk, supplemented from the second week with a fortifier. Special preterm formula might serve as a good alternative in case when breast milk is not available.