Relation of cord serum levels of growth hormone, insulin-like growth factors, insulin-like growth factor binding proteins, leptin, and interleukin-6 with birth weight, birth length, and head circumference in term and preterm neonates

OBJECTIVES: Fetal growth process is governed by multiple factors. We investigated the relation of insulin-like growth factors (IGFs). IGF binding proteins (IGFBPs), leptin, and interleukin-6 (IL-6) with intrauterine growth in preterm and term neonates. METHODS: Thirty-eight preterm and 43 term neonates were recruited. Anthropometric measures were recorded and umbilical cord blood samples were collected at birth. RESULTS: Birth weight (BW). birth length (BL), ponderal index. head circumference (HC). and cord serum levels of albumin. prealbumin. retinol-binding protein (RBP). total and free IGF-I, IGF-II. IGFBP-3, acid-labile subunit (ALS). and leptin were significantly lower, whereas levels of IGFBP-1, IGFBP-2, and IL-6 were significantly higher in preterm than in term neonates (P < 0.05). Total and free IGF-I. ALS. and leptin had significantly positive correlations, whereas IGFBP-2 had a significantly negative correlation. with BW and BL in preterm plus term neonates. Forward stepwise multivariate regression analysis showed that gestational age (GA). IGFBP-2. leptin, and free IGF-I axe significant predictors of BW GA. IGFBP-2. ALS. transferrin. and leptin are significant predictors of BL; and GA and free IGF-I are significant predictors of HC in preterm and term neonates. CONCLUSIONS: Our results suggest that IGF-I, IGF-II, IGFBP-2. ALS, and leptin play important roles in intrauterine growth.