Optimal Growth of Preterm Infants

Abstract

The cause of growth restriction in preterm infants is multifactorial, but it has been estimated that about 50% of the variance in early postnatal growth can be attributed to nutrition. Very low birth weight (VLBW) infants who were born small-for-gestational age (SGA) seem to have the highest risk to become growth restricted. Possibly, the intrauterine growth-retarded preterm infant is metabolically different from its appropriately grown counterpart and therefore has different nutritional needs. Neonatal nutrition and the resulting postnatal growth are major determinants in the short- and long-term outcomes of preterm neonates. Although having favorable effects on neurodevelopmental outcome, rapid postnatal weight gain after a period of nutritional restriction is associated with the development of insulin resistance and metabolic syndrome in later life. It seems likely that minimization of postnatal growth failure will decrease the need for catch-up growth and thereby decrease the risk of developing cardiovascular risk factors. Monitoring postnatal growth with current growth charts is complicated. Most growth charts that are currently being used are a reflection of current (nutritional) practices and are not a prescription of how VLBW should grow under optimal conditions. In addition to body weight, other aspects of growth such as lean body mass and length gain should also be taken into account when assessing the quality of postnatal growth. Noninvasive measurements of infant body composition are useful tools in evaluating the success of different nutritional interventions. However, all currently available methods have substantial drawbacks. A relatively new and promising method is air displacement plethysmography. This method still needs to be validated in preterm neonates. In conclusion, neonatal nutrition is a major determinant in the short- and long-term outcomes of preterm neonates. Monitoring postnatal growth is complicated by the lack of prescriptive growth charts and noninvasive measurements to assess the quality of growth.

Fetal undernutrition is associated with perinatal sex-dependent alterations in oxidative status

“…Suboptimal fetal nutrition is usually followed by a period of accelerated weight gain during early postnatal life, known as catch-up growth. This is a compensatory mechanism to balance growth retardation in utero, but seems to be deleterious, contributing to the development of cardiovascular and metabolic alterations later on [32][33][34]. The rat model of IUGR used in the present study exhibits this accelerated growth process during suckling period;…”

Full oral feeding is possible before discharge even in extremely preterm infants

“…The goal for the nutritional management of preterm infants is to achieve a growth rate and a composition of weight gain similar to those of a normal foetus. This strategy was initially proposed by the American Academy of Pediatrics and subsequently indicated by the European Society of Paediatric Gastroenterology, Hepatology and Nutrition Committee on Nutrition and several other authors . Despite these goals, poor postnatal growth is almost a universal problem among very low birthweight infants .…”

Postdischarge growth assessment in very low birth weight infants

“…Unfortunately, this goal is rarely achieved because of chronic undernutrition and poor growth345). Neonatal nutrition and the resulting postnatal growth are major determinants of short- and long-term outcomes for preterm infants678).…”