title: The Current Recommended Vitamin D Intake Guideline for Diet and Supplements During Pregnancy Is Not Adequate to Achieve Vitamin D Sufficiency for Most Pregnant Women.
abstract: BACKGROUND
  The aims of this study were to determine if pregnant women consumed the recommended vitamin D through diet alone or through diet and supplements, and if they achieved the current reference range vitamin D status when their reported dietary intake met the current recommendations.
  
  
  METHODS
  Data and banked blood samples collected in second trimester from a subset of 537 women in the APrON (Alberta Pregnant Outcomes and Nutrition) study cohort were examined. Frozen collected plasma were assayed using LC-MS/MS (liquid chromatography-tandem mass spectrometry) to determine 25(OH)D2, 25(OH)D3, 3-epi-25(OH)D3 concentrations. Dietary data were obtained from questionnaires including a Supplement Intake Questionnaire and a 24-hour recall of the previous day's diet.
  
  
  RESULTS
  Participants were 87% Caucasian; mean (SD) age of 31.3 (4.3); BMI 25.8 (4.7); 58% were primiparous; 90% had education beyond high school; 80% had a family income higher than CAN $70,000/year. 25(OH)D2, 25(OH)D3, and 3-epi-25(OH)D3) were identified in all of the 537 plasma samples;3-epi-25(OH)D3 contributed 5% of the total vitamin D. The median (IQR) total 25(OH)D (D2+D3) was 92.7 (30.4) nmol/L and 20% of women had 25(OH)D concentration < 75 nmol/L. The median (IQR) reported vitamin D intake from diet and supplements was 600 (472) IU/day. There was a significant relationship between maternal reported dietary vitamin D intake (diet and supplement) and 25(OH)D and 3-epi-25(OH)D3 concentrations in an adjusted linear regression model.
  
  
  CONCLUSIONS
  We demonstrated the current RDA (600 IU/ day) may not be adequate to achieve vitamin D status >75 nmol/L in some pregnant women who are residing in higher latitudes (Calgary, 51°N) in Alberta, Canada and the current vitamin D recommendations for Canadian pregnant women need to be re-evaluated.
authors.affiliation: Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Fariba
authors.identifier: http://orcid.org/0000-0002-2229-2054
authors.initials: F
authors.lastname: Aghajafari
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Field
authors.affiliation: Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Bonnie J
authors.initials: BJ
authors.lastname: Kaplan
authors.affiliation: Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Doreen M
authors.initials: DM
authors.lastname: Rabi
authors.affiliation: Research and Development, Doctor's Data, Inc., St. Charles, Illinois, United States of America.
authors.forename: Jack A
authors.initials: JA
authors.lastname: Maggiore
authors.affiliation: Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Maeve
authors.initials: M
authors.lastname: O'Beirne
authors.affiliation: Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: David A
authors.initials: DA
authors.lastname: Hanley
authors.affiliation: Department of Public Health and Community Medicine, Tufts University, Boston, Massachusetts, United States of America.
authors.forename: Misha
authors.initials: M
authors.lastname: Eliasziw
authors.affiliation: Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Deborah
authors.initials: D
authors.lastname: Dewey
authors.affiliation: Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Amy
authors.initials: A
authors.lastname: Weinberg
authors.affiliation: Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Sue J
authors.initials: SJ
authors.lastname: Ross
mesh_terms: D000328:Adult; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D009035:Mothers; D009752:Nutritional Status; D017410:Practice Guidelines as Topic; D011247:Pregnancy; D014807:Vitamin D / Q000097:blood / Q000737:chemistry / Q000494:pharmacology*; D014808:Vitamin D Deficiency / Q000517:prevention & control
chemical_list: D014807:Vitamin D