Vitamin D insufficiency in pregnant and nonpregnant women of childbearing age in the United States

Am J Obstet Gynecol. 2010 May;202(5):436.e1-8. doi: 10.1016/j.ajog.2009.11.036. Epub 2010 Jan 12.


Objective: We evaluated vitamin D insufficiency in a nationally representative sample of women and assessed the role of vitamin supplementation.

Study design: We conducted secondary analysis of 928 pregnant and 5173 nonpregnant women aged 13-44 years from the National Health and Nutrition Examination Survey 2001-2006.

Results: The mean 25-hydroxyvitamin D (25[OH]D) level was 65 nmol/L for pregnant women and 59 nmol/L for nonpregnant women. The prevalence of 25(OH)D<75 nmol/L was 69% and 78%, respectively. Pregnant women in the first trimester had similar 25(OH)D levels as nonpregnant women (55 vs 59 nmol/L), despite a higher proportion taking vitamin D supplementation (61% vs 32%). However, first-trimester women had lower 25(OH)D levels than third-trimester women (80 nmol/L), likely from shorter duration of supplement use.

Conclusion: Adolescent and adult women of childbearing age have a high prevalence of vitamin D insufficiency. Current prenatal multivitamins (400 IU vitamin D) helped to raise serum 25(OH)D levels, but higher doses and longer duration may be required.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Dietary Supplements
  • Female
  • Humans
  • Logistic Models
  • Nutrition Surveys
  • Pregnancy
  • Pregnancy Complications / epidemiology*
  • Pregnancy Complications / therapy
  • United States / epidemiology
  • Vitamin D / administration & dosage
  • Vitamin D Deficiency / epidemiology*
  • Vitamin D Deficiency / therapy
  • Young Adult


  • Vitamin D