Evaluation of Vitamin D Requirements During Pregnancy
Condition: Vitamin D Deficiency
MeSH terms: Vitamin D Deficiency
Study type: Interventional
Phase: Phase 3

Summary: 
      The purpose of this study is to determine the effectiveness of vitamin D supplementation
      during pregnancy starting at the beginning of the second trimester. Mothers will be
      randomized to one of three vitamin D dosing groups: 400, 2,000 or 4,000 international units
      per day. It is hypothesized that the highest dosing regimen will result in a better vitamin D
      status of women regardless of their ethnicity or race.
    

Detailed description: 
      The prevalence of hypovitaminosis D in reproductive aged African-American women occurs at a
      rate of > 40%. Two factors have contributed to this public health problem: an inadequate DRI
      for vitamin D and avoidance of sun exposure/use of sunscreen. This startling rate of
      hypovitaminosis D requires that the DRI for vitamin D in pregnancy be evaluated in a detailed
      manner. The Cochrane Library (2002) released a report stating that there is insufficient data
      to evaluate the effects of vitamin D supplementation during pregnancy. Recently, the safety
      of prolonged supplementation with up to 25x's DRI (10,000 IU/day) was demonstrated in
      nonpregnant adults. It is essential to determine what dose of vitamin D is required to
      eliminate hypovitaminosis D during pregnancy and provide the fetus/neonate with adequate
      vitamin D stores during development and growth, particularly in darkly pigmented individuals.
      The aim of this research proposal, then, is to determine the efficacy, effectiveness, and
      safety of maternal vitamin D supplementation (as a function of ethnicity and UV exposure) in
      the prevention of hypovitaminosis D in the pregnant mother and her fetus/neonate. We
      hypothesize that darkly pigmented mothers will require substantially higher oral
      supplementation with vitamin D to eliminate hypovitaminosis D as compared to their Caucasian
      counterparts. We propose a comprehensive clinical trial to test our hypothesis. Mothers at 12
      weeks' gestation will be randomized to one of three vitamin D treatment groups:

        1. Control, 400-,

        2. 2,000-, or

        3. 4,000 IU/day to be continued throughout pregnancy.

      Calcium and vitamin D homeostasis and skeletal remodeling in the mother will be monitored
      closely throughout the pregnancy. Bone density of the mother will be measured at 12 weeks'
      gestation and one-month postpartum. Follow-up growth and skeletal integrity assessments of
      the infant will be performed at birth, 1, 6 and 12 months stratified by infant feeding
      regime. Through these proposed studies, the prevalence of hypovitaminosis D among mothers,
      their developing fetuses and neonates, and the utility of maternal therapeutic intervention
      with vitamin D for both mother and fetus/infant will be assessed.
    

Intervention name(s): cholecalciferol (vitamin D3); cholecalciferol
Intervention type(s): Drug; Drug
Intervention description(s): randomized control trial of three vitamin D doses: 400, 2000 and 4000 IU/day; comparing vitamin D requirements of pregnant women and their fetuses from 12 weeks' gestation through pregnancy
Other intervention name(s): vitamin D3
Intervention MeSH terms: Vitamin D; Ergocalciferols; Cholecalciferol; Vitamins
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Prevention
Keywords: vitamin D; cholecalciferol; pregnancy; bone mineral density