GROWTH-HORMONE, INSULIN-LIKE GROWTH-FACTOR-I AND INSULIN-LIKE-GROWTH-FACTOR BINDING PROTEIN-3 ARE REGULATED DIFFERENTLY IN SMALL-FOR-GESTATIONAL-AGE AND APPROPRIATE-FOR-GESTATIONAL-AGE NEONATES

Growth hormone (GH), insulin-like growth factor-I (IGF-I) and IGF-bind ing protein-3 (IGFBP-3) were measured in 90 neonates during the first 5 days of life. Twenty-six small-for-gestational-age (SGA) neonates we re compared with 64 appropriate-for-gestational-age (ACA) neonates, Th ere were no differences in nutritional status between the 2 groups. Me an GH levels were significantly higher in the SGA group (53.4 +/- 30.8 vs. 39.9 +/- 23.3 mu g/l; p < 0.05), In both groups GH levels correla ted with birth weight (expressed as SDS) but not with gestational age. IGF-I levels were significantly lower in SGA neonates (6.6 +/- 4.0 vs . 11.7 +/- 8.2 ng/ml; p < 0.01). In SGA neonates with short stature, I GF-I levels were lower and GH levels were higher than in normal statur e SGA neonates, IGFBP-3 levels were significantly lower in SGA neonate s than in AGA neonates (0.72 +/- 0.40 vs. 0.98 +/- 0.43 mu g/l; p < 0. 01), IGF-I and IGFBP-3 correlated with gestational age in AGA but not in SGA neonates and there was no correlation with birth weight in eith er group, Our data provide evidence for a graduation in the severity o f impact of fetal 'malnutrition' on the somatotropic axis and on: intr auterine growth. The most severe state (SGA with short stature) was as sociated with a GH-resistance syndrome, characterized by very low IGF- I levels and high GH levels.