title: Neonatal leptin levels are strongly associated with female gender, birth length, IGF-I levels and formula feeding.
abstract: OBJECTIVE
  To investigate predictors of circulating leptin in healthy full-term newborns and to explore the relationship with anthropometric variables, serum levels of adiponectin and the major components of the IGF system at birth. To explore whether leptin levels are regulated by breastfeeding vs. formula feeding.
  
  
  METHODS
  Observational cross-sectional study.
  
  
  METHODS
  Three hundred and nineteen healthy full-term newborns delivered during 1999 in Athens, Greece.
  
  
  METHODS
  Anthropometric measurements, formula feeding information and blood samples were obtained. Leptin and adiponectin determinations were performed using a radioimmunoassay (RIA).
  
  
  RESULTS
  Multivariate regression analyses showed that leptin levels were positively associated with female gender, newborn length, ponderal index and IGF-I levels, but not with adiponectin levels. Newborns who were fed exclusively with milk formulas had more than twice the leptin levels of those who were exclusively breastfed.
  
  
  CONCLUSIONS
  Leptin levels are positively related to female gender and anthropometric characteristics of neonates but, contrary to studies in adults, are not correlated with adiponectin levels. We also found evidence that formula feeding imparts a considerable increase in leptin levels in newborns.
authors.affiliation: Department of Hygiene and Epidemiology, Athens University Medical School, Athens, Greece. epetrid@med.uoa.gr
authors.forename: Eleni
authors.initials: E
authors.lastname: Petridou
authors.forename: Christos S
authors.initials: CS
authors.lastname: Mantzoros
authors.forename: Maria
authors.initials: M
authors.lastname: Belechri
authors.forename: Alkistis
authors.initials: A
authors.lastname: Skalkidou
authors.forename: Nick
authors.initials: N
authors.lastname: Dessypris
authors.forename: Eugenia
authors.initials: E
authors.lastname: Papathoma
authors.forename: Heraklis
authors.initials: H
authors.lastname: Salvanos
authors.forename: Jennifer H
authors.initials: JH
authors.lastname: Lee
authors.forename: Simeon
authors.initials: S
authors.lastname: Kedikoglou
authors.forename: George
authors.initials: G
authors.lastname: Chrousos
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Trichopoulos
mesh_terms: D052242:Adiponectin; D000328:Adult; D000886:Anthropometry; D001827:Body Height / Q000502:physiology*; D001903:Bottle Feeding; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007231:Infant, Newborn / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood; D020738:Leptin / Q000097:blood*; D008297:Male; D012727:Sex Characteristics; D047929:Term Birth
chemical_list: D052242:Adiponectin; D036341:Intercellular Signaling Peptides and Proteins; D020738:Leptin; D007334:Insulin-Like Growth Factor I