title: Prenatal vitamin use and vitamin D status during pregnancy, differences by race and overweight status.
abstract: OBJECTIVE
  We aimed to study whether prenatal vitamin (PNV) use protects against low 25-hydroxyvitamin D (25[OH]D) levels in all women and particularly in obese and black women who are both at risk of vitamin D deficiency and poor pregnancy outcomes.
  
  
  METHODS
  We studied 1019 women enrolled in a prospective study at Brigham and Women's Hospital in Boston, from 2007 to 2009. We used multivariable logistic regression to analyze associations of PNV use and odds of vitamin D deficiency defined as 25[OH]D levels <50 nmol l(-1).
  
  
  RESULTS
  In all, 56% of black and 86% of white women reported pre- and/or postconceptional PNV use. In the first trimester, 75% of black and 19% of white women were vitamin D deficient. Lack of PNV use among black women was not associated with vitamin D deficiency (adjusted odds ratio (OR) 1.0, 95% confidence interval (CI) 0.4, 2.3) but was among white women (OR 3.5, 95% CI 2.1, 5.8) (interaction P<0.01).
  
  
  CONCLUSIONS
  Ongoing trials of vitamin D supplementation during pregnancy should consider potential effect modification by race/ethnicity.
authors.affiliation: 1] Department of Neonatology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA [2] Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA [3] Department of Pediatrics, Harvard Medical School, Boston, MA, USA.
authors.forename: H H
authors.initials: HH
authors.lastname: Burris
authors.affiliation: Division of Maternal Fetal Medicine, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: A
authors.initials: A
authors.lastname: Thomas
authors.affiliation: 1] Division of Maternal Fetal Medicine, Brigham and Women's Hospital, Boston, MA, USA [2] Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Zera
authors.affiliation: 1] Division of Maternal Fetal Medicine, Brigham and Women's Hospital, Boston, MA, USA [2] Division of Maternal Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Biology, Harvard Medical School, Boston, MA, USA.
authors.forename: T F
authors.initials: TF
authors.lastname: McElrath
mesh_terms: D000328:Adult; D001741:Black or African American; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D016015:Logistic Models; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications*; D016017:Odds Ratio; D011247:Pregnancy; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First; D039401:Prenatal Nutritional Physiological Phenomena; D011446:Prospective Studies; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000188:drug therapy* / Q000208:ethnology*; D014815:Vitamins / Q000627:therapeutic use*; D044465:White People
chemical_list: D014815:Vitamins; D014807:Vitamin D; C104450:25-hydroxyvitamin D