title: Vitamin D status among preterm and full-term infants at birth.
abstract: BACKGROUND
  Risk factors for maternal vitamin D deficiency and preterm birth overlap, but the distribution of 25-hydroxyvitamin D (25(OH)D) levels among preterm infants is not known. We aimed to determine the associations between 25(OH)D levels and gestational age.
  
  
  METHODS
  We measured umbilical cord plasma levels of 25(OH)D from 471 infants born at Brigham and Women's Hospital in Boston. We used generalized estimating equations to determine whether preterm (<37 wks' gestation) or very preterm (<32 wks' gestation) infants had greater odds of having 25(OH)D levels below 20 ng/ml than more mature infants. We adjusted for potential confounding by season of birth, maternal age, race, marital status, and singleton or multiple gestation.
  
  
  RESULTS
  Mean cord plasma 25(OH)D level was 34.0 ng/ml (range: 4.1-95.3 and SD: 14.1). Infants born before 32 wks' gestation had increased odds of having 25(OH)D levels below 20 ng/ml in unadjusted (odds ratio (OR): 2.2; 95% confidence interval (CI): 1.1-4.3) and adjusted models (OR: 2.4; 95% CI: 1.2-5.3) as compared with more mature infants.
  
  
  CONCLUSIONS
  Infants born in <32 wks' gestation are at higher risk than more mature infants for low 25(OH)D levels. Further investigation of the relationships between low 25(OH)D levels and preterm birth and its sequelae is thus warranted.
authors.affiliation: 1] Harvard Medical School, Boston, Massachusetts [2] Department of Neonatology, Beth Israel Deaconess Medical Center, Boston, Massachusetts [3] Division of Newborn Medicine, Boston Children's Hospital, Boston, Massachusetts.
authors.forename: Heather H
authors.initials: HH
authors.lastname: Burris
authors.affiliation: 1] Harvard Medical School, Boston, Massachusetts [2] Division of Newborn Medicine, Boston Children's Hospital, Boston, Massachusetts [3] Division of Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Linda J
authors.initials: LJ
authors.lastname: Van Marter
authors.affiliation: 1] Harvard Medical School, Boston, Massachusetts [2] Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: McElrath
authors.affiliation: Institute of Public Health, University of Heidelberg, Heidelberg, Germany.
authors.forename: Patrik
authors.initials: P
authors.lastname: Tabatabai
authors.affiliation: 1] Harvard Medical School, Boston, Massachusetts [2] Channing Laboratory, Brigham and Women's Hospital, Boston, Massachusetts [3] Division of Pulmonology and Critical Care Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Augusto A
authors.initials: AA
authors.lastname: Litonjua
authors.affiliation: 1] Harvard Medical School, Boston, Massachusetts [2] Channing Laboratory, Brigham and Women's Hospital, Boston, Massachusetts [3] Division of Pulmonology and Critical Care Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Weiss
authors.affiliation: 1] Harvard Medical School, Boston, Massachusetts [2] Division of Newborn Medicine, Boston Children's Hospital, Boston, Massachusetts [3] Division of Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Helen
authors.initials: H
authors.lastname: Christou
mesh_terms: D005312:Fetal Blood / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D014807:Vitamin D / Q000097:blood*
chemical_list: D014807:Vitamin D