title: Serum leptin levels in twins and singleton newborns.
abstract: OBJECTIVE
  Leptin is produced by the human placenta besides adipose tissue and is suggested to be related to fetal growth. In order to find out whether multiple pregnancy is a factor affecting serum leptin levels, we compared neonatal serum leptin concentrations of twins and singleton newborns who were all appropriate for gestational age (AGA).
  
  
  METHODS
  Thirty newborns were studied. Group 1 consisted of 15 infants from twin pregnancies and group 2 (control group) consisted of 15 infants from singleton pregnancies. Serum samples were taken at 24 hours following delivery and leptin concentrations were measured.
  
  
  RESULTS
  There were no significant differences in birth weight, gestational age and male/female ratio between infants of twin and single gestations. However, serum leptin concentrations of twins (mean +/- SEM: 1.13 +/- 0.35 ng/ml) were significantly lower than of the singleton infants (4.27 +/- 0.63 ng/ml) (p < 0.001).
  
  
  CONCLUSIONS
  Twin pregnancy might be a factor affecting serum leptin concentrations in newborn infants.
authors.affiliation: Department of Neonatology, Gazi University Medical School, Turkey. esra_onal@hotmail.com
authors.forename: E Esra
authors.initials: EE
authors.lastname: Onal
authors.forename: Füsun Kitapçi
authors.initials: FK
authors.lastname: Uysal
authors.forename: Peyami
authors.initials: P
authors.lastname: Cinaz
authors.forename: Aysun
authors.initials: A
authors.lastname: Bideci
authors.forename: Uğur
authors.initials: U
authors.lastname: Dilmen
mesh_terms: D001724:Birth Weight; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D020738:Leptin / Q000097:blood*; D008297:Male; D011247:Pregnancy; D011272:Pregnancy, Multiple / Q000502:physiology*
chemical_list: D020738:Leptin