title: Prevalence and predictors of vitamin D deficiency based on maternal mid-gestation and neonatal cord bloods: The Generation R Study.
abstract: Population-based studies have confirmed that the prevalence of vitamin D deficiency is substantial in many societies, and is of particular concern in pregnant women. Vitamin D deficiency during pregnancy is associated with a wide range of adverse maternal and offspring health outcomes. To date, studies of vitamin D deficiency during pregnancy have focused on measurements at one or two time points in isolation. We examined both midgestation and cord blood 25 hydroxyvitamin D (25OHD) concentration and explored the prevalence and correlates of vitamin D deficiency in a large ethnically diverse cohort of pregnant women and their infants in the Netherlands.
  
  
  
  This study was embedded in the Generation R Study, a population-based prospective cohort from fetal life onwards in Rotterdam, The Netherlands. Using a highly sensitive tandem mass spectroscopy-based assay, we measured 25OHD in 7256 midgestation samples (mean gestation 20.6 weeks) and 5023 neonatal cord blood samples (mean gestation 40.0 weeks). Using a conservative threshold of less than 25nmol/L to define vitamin D deficiency, we examined the prevalence and socio-demographic correlates of vitamin D deficiency in mothers and infants. We also derived a measure of vitamin D deficiency based on the two time points in order to explore persistent vitamin D deficiency in mother-infant pairs.
  
  
  
  The prevalence of vitamin D deficiency at midgestation was 26%, while in neonates 46% were deficient. 21% of the mother-infant pairs had persistent vitamin D deficiency (i.e., deficient in maternal and cord samples) and an additional 29% were vitamin D deficient in one of the two samples only. Persistent vitamin D deficiency was strongly associated with non-European ancestry and spring birth.
  
  
  
  A sizeable proportion of women and their neonatal offspring in the Generation R cohort were vitamin D deficient. In light of the large body of evidence linking vitamin D deficiency with adverse health outcomes for pregnant women and their offspring, our findings indicate a large unmet need in this population. In particular, women and infants from non-European ethnic background are at high risk of vitamin D deficiency.
authors.affiliation: Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia.
authors.forename: Anna A E
authors.initials: AAE
authors.lastname: Vinkhuyzen
authors.affiliation: Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia; Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, QLD 4076, Australia.
authors.forename: Darryl W
authors.initials: DW
authors.lastname: Eyles
authors.affiliation: Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia; Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, QLD 4076, Australia.
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Burne
authors.affiliation: The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, The Netherlands; Department of Child and Adolescent Psychiatry/Psychology, Erasmus MC, University Medical Center Rotterdam, The Netherlands.
authors.forename: Laura M E
authors.initials: LME
authors.lastname: Blanken
authors.affiliation: The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, The Netherlands; Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, The Netherlands.
authors.forename: Claudia J
authors.initials: CJ
authors.lastname: Kruithof
authors.affiliation: Department of Child and Adolescent Psychiatry/Psychology, Erasmus MC, University Medical Center Rotterdam, The Netherlands.
authors.forename: Frank
authors.initials: F
authors.lastname: Verhulst
authors.affiliation: The Generation R Study Group, Erasmus MC, University Medical Center Rotterdam, The Netherlands; Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, The Netherlands; Department of Pediatrics, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: Vincent W
authors.initials: VW
authors.lastname: Jaddoe
authors.affiliation: Department of Epidemiology, Erasmus MC, University Medical Center Rotterdam, The Netherlands; Department of Child and Adolescent Psychiatry/Psychology, Erasmus MC, University Medical Center Rotterdam, The Netherlands.
authors.forename: Henning
authors.initials: H
authors.lastname: Tiemeier
authors.affiliation: Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia; Queensland Centre for Mental Health Research, The Park Centre for Mental Health, Wacol, QLD 4076, Australia. Electronic address: j.mcgrath@uq.edu.au.
authors.forename: John J
authors.initials: JJ
authors.lastname: McGrath
mesh_terms: D000328:Adult; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D015995:Prevalence; D011446:Prospective Studies; D012621:Seasons; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: 25 Hydroxyvitamin D; Cord blood; Epidemiology; Prenatal; Risk factors; Vitamin D