title: Predictors of serum ferritin and serum soluble transferrin receptor in newborns and their associations with iron status during the first 2 y of life.
abstract: BACKGROUND
  Adequate iron status at birth may prevent iron deficiency in early childhood.
  
  
  OBJECTIVE
  We aimed to identify predictors of serum ferritin (SF) and serum soluble transferrin receptor (sTfR) in healthy newborns and to relate these iron indexes to iron status in the first 2 y of life.
  
  
  METHODS
  Using bivariate correlations and linear regression, we related various factors in pregnancy to SF (n=363) and sTfR (n=350) in healthy, term infants. Measurements of cord SF and sTfR were compared with those of SF and sTfR at 6, 12, and 24 mo. All 4 measurements were available for 191 and 169 infants for SF and sTfR, respectively.
  
  
  RESULTS
  Geometric mean (and 95% CI) cord SF and sTfR measurements were 159 (148, 171) microg/L and 7.3 (7.0, 7.6) mg/L, respectively. Cord SF correlated with sTfR (rho=-0.21, P<0.001). In regression analysis, cord SF correlated with smoking and the use of iron supplements during pregnancy (partial r=-0.12 and 0.16; P<0.05 for both). Cord sTfR was associated with first trimester BMI, gestational age, and male sex (partial r=0.30, 0.24, and 0.19, respectively; P<0.01 for all). Cord SF correlated with SF at 6, 12, and 24 mo (rho=0.45, 0.31, and 0.16 respectively; P<0.05 for all). At age 6 mo, 16 of 17 infants with SF <15 mug/L were boys.
  
  
  CONCLUSIONS
  Cessation of smoking and adequate iron prophylaxis during pregnancy may improve iron status in infancy. Cord SF is a predictor of iron status in the first 2 y of life. Boys are at particular risk of low iron status in early infancy.
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway. gry.hay@medisin.uio.no
authors.forename: Gry
authors.initials: G
authors.lastname: Hay
authors.forename: Helga
authors.initials: H
authors.lastname: Refsum
authors.forename: Andrew
authors.initials: A
authors.lastname: Whitelaw
authors.forename: Elisabeth Lind
authors.initials: EL
authors.lastname: Melbye
authors.forename: Egil
authors.initials: E
authors.lastname: Haug
authors.forename: Berit
authors.initials: B
authors.lastname: Borch-Iohnsen
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005293:Ferritins / Q000097:blood*; D005312:Fetal Blood; D006801:Humans; D007231:Infant, Newborn / Q000097:blood*; D007501:Iron / Q000378:metabolism*; D008137:Longitudinal Studies; D008297:Male; D011247:Pregnancy / Q000378:metabolism*; D011990:Receptors, Transferrin / Q000097:blood*; D012044:Regression Analysis; D012737:Sex Factors
chemical_list: D011990:Receptors, Transferrin; D005293:Ferritins; D007501:Iron