Nutritional management and growth hormone treatment of preterm infants born small for gestational age

In severe cases of intrauterine growth retardation, elective preterm delivery may provide the possibility for nutritional intervention to prevent some of the long-term consequences of the catabolic condition in utero. Neonatal nutritional management is aimed at providing a high protein intake of up to 4 g/kg/day in order to obtain the rapid increase in protein that is seen in normally growing infants during the early postnatal period. Unfortunately, due to impaired production of urea, high plasma levels of ammonia, which may be rate limiting with respect to an optimal gain in protein, are often observed in the preterm infant born small for gestational age (SGA). In an attempt to stimulate protein synthesis in preterm infants born SGA, growth hormone (GH) treatment was given to seven such infants during the early postnatal period. The infants received daily subcutaneous injections of GH (1.0 IU/kg/day) from postnatal day 7 until a body weight of 2000 g was reached (postnatal week 7-8). A further seven preterm infants born SGA were studied as controls. GH treatment had no significant effects on growth, body composition, net protein gain and glucose metabolism. Furthermore, plasma levels of insulin-like growth factor I (IGF-1) and IGF-binding protein-3 revealed a normal developmental increase and were not significantly altered by GH treatment. These results may be explained by a relative GH insensitivity or resistance during this period of early preterm life.