title: Effects of cord serum insulin, IGF-II, IGFBP-2, IL-6 and cortisol concentrations on human birth weight and length: pilot study.
abstract: BACKGROUND
  The IGF system is recognised to be important for fetal growth. We previously described increased Insulin-like growth factor binding protein (IGFBP)-2 cord serum concentrations in intra-uterine growth retardation (IUGR) compared with appropriate for gestational age (AGA) newborns, and a positive relationship of IGFBP-2 with Interleukin (IL)-6. The role of cortisol in the fetus at birth is largely unknown, and interactions among peptides are their real effect on birth size is unknown. Furthermore, almost all studies have previously assayed peptides in serum several years after birth, and follow-up data from pregnancy are always lacking. This study aimed at establishing and clarifying the effect of cord serum insulin, IGF-II, IGFBP-2, cortisol and IL-6 concentrations on birth length and weight.
  
  
  METHODS
  23 IUGR and 37 AGA subjects were followed up from the beginning of pregnancy, and were of comparable gestational age. Insulin, IGF-II, IGFBP-2, cortisol and IL-6 concentrations were assayed in cord serum at birth, and a multiple regression model was designed and applied to assess which were the significant biochemical determinants of birth size.
  
  
  RESULTS
  Insulin, cortisol, and IL-6, showed similar concentrations in IUGR and AGA as previously described, whereas IGF-II was lower, and IGFBP-2 increased in IUGR compared with AGA. IGF-II serum concentration was found to have a significant positive effect on both birth length (r:(:)0.546; p: 0.001) and weight (r:0.679; p: 0.0001). IGFBP-2 had a near significant negative effect on both birth weight (r:-0.342; p: 0.05) and length (r:-0.372; p:0.03).
  
  
  CONCLUSIONS
  IGF-II cord serum concentration was shown to have a significant positive effect on both birth length and weight, whereas IGFBP-2 had a significant negative effect. Insulin, cortisol, and IL-6 cord serum concentrations had no significant effect on birth size.
authors.affiliation: Department of Paediatrics, University Hospital of Parma, Parma, Italy.
authors.forename: Arianna
authors.initials: A
authors.lastname: Smerieri
authors.forename: Maddalena
authors.initials: M
authors.lastname: Petraroli
authors.forename: Maria Angela
authors.initials: MA
authors.lastname: Ziveri
authors.forename: Cecilia
authors.initials: C
authors.lastname: Volta
authors.forename: Sergio
authors.initials: S
authors.lastname: Bernasconi
authors.forename: Maria E
authors.initials: ME
authors.lastname: Street
mesh_terms: D001724:Birth Weight / Q000502:physiology*; D001827:Body Height / Q000502:physiology*; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007231:Infant, Newborn; D007328:Insulin / Q000097:blood*; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000097:blood*; D007335:Insulin-Like Growth Factor II / Q000378:metabolism*; D015850:Interleukin-6 / Q000097:blood*; D010865:Pilot Projects; D011247:Pregnancy
chemical_list: C035170:IGF2 protein, human; C508600:IL6 protein, human; D007328:Insulin; D018971:Insulin-Like Growth Factor Binding Protein 2; D015850:Interleukin-6; D007335:Insulin-Like Growth Factor II; D006854:Hydrocortisone