title: Daily Cholecalciferol Supplementation during Pregnancy Alters Markers of Regulatory Immunity, Inflammation, and Clinical Outcomes in a Randomized Controlled Trial.
abstract: BACKGROUND
  Vitamin D deficiency is widespread in pregnancy and has been associated with adverse health conditions in mothers and infants. Vitamin D supplementation in pregnancy may support the maintenance of pregnancy by its effects on innate and adaptive immunity.
  
  
  OBJECTIVE
  We assessed the effects of vitamin D supplementation during pregnancy on vitamin D status and markers of immune function associated with adverse pregnancy outcomes.
  
  
  METHODS
  We conducted a randomized, controlled, double-blind intervention of 2 doses of cholecalciferol (400 and 2000 IU/d) from <20 wk to delivery in 57 pregnant women. Vitamin D status, regulatory and inflammatory T cells, markers of innate immunity and systemic inflammation, and clinical outcomes including maternal blood pressure and birth weight were assessed at 26 and 36 wk of pregnancy.
  
  
  RESULTS
  Supplementation with 2000 IU/d vitamin D had a greater effect on the change in vitamin D status over pregnancy (P < 0.0001) and the final value at 36 wk (P < 0.0001) than 400 IU/d, increasing serum 25-hydroxyvitamin D from 81.1 nmol/L at baseline to 116 nmol/L at 36 wk and from 69.6 nmol/L at baseline to 85.6 nmol/L at 36 wk, respectively. The 2000-IU/d group had 36% more interleukin-10+regulatory CD4+T cells at 36 wk than did the 400-IU/d group (P < 0.007). The daily intake of 2000 compared with 400 IU/d tended to dampen the pregnancy-related increase in diastolic blood pressure by 1.3-fold (P = 0.06) and increase birth weight by 8.6% (P = 0.06), but these differences were not statistically significant.
  
  
  CONCLUSIONS
  Supplementation with 2000 IU/d is more effective at increasing vitamin D status in pregnant women than 400 IU/d and is associated with increased regulatory T cell immunity that may prevent adverse outcomes caused by excess inflammation. This trial was registered at clinicaltrials.gov as NCT01417351.
authors.affiliation: Graduate Group in Nutritional Biology and mszerofsky@ucdavis.edu.|USDA Western Human Nutrition Research Center, Davis, CA.
authors.forename: Melissa S
authors.initials: MS
authors.lastname: Zerofsky
authors.affiliation: Division of Maternal/Fetal Medicine, Davis Medical Center, University of California, Davis, Davis, CA; and.
authors.forename: Bryon N
authors.initials: BN
authors.lastname: Jacoby
authors.affiliation: USDA Western Human Nutrition Research Center, Davis, CA.
authors.forename: Theresa L
authors.initials: TL
authors.lastname: Pedersen
authors.affiliation: USDA Western Human Nutrition Research Center, Davis, CA.
authors.forename: Charles B
authors.initials: CB
authors.lastname: Stephensen
mesh_terms: D000328:Adult; D015415:Biomarkers; D015496:CD4-Positive T-Lymphocytes; D002762:Cholecalciferol / Q000008:administration & dosage* / Q000494:pharmacology*; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D016753:Interleukin-10 / Q000378:metabolism; D011247:Pregnancy; D051193:Toll-Like Receptors
chemical_list: D015415:Biomarkers; D016207:Cytokines; D051193:Toll-Like Receptors; D016753:Interleukin-10; D002762:Cholecalciferol
keywords: T cell; clinical trial; cytokines; pregnancy; vitamin D