Evaluation of Vitamin D Requirements During Pregnancy

Study Overview
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Brief Summary
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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
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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: Control, 400-, 2,000-, or 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.

Official Title
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Evaluation of Vitamin D Requirements During Pregnancy

Conditions
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Vitamin D Deficiency

Intervention / Treatment
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* Drug: cholecalciferol (vitamin D3)
* Drug: cholecalciferol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women who are within the ages of 16-45 years In good general health Less than 12 weeks pregnant (based on last menstrual period) Exclusion Criteria: Mothers with preexisting type I or type II diabetes Mothers with preexisting hypertension Mothers with preexisting parathyroid disease or uncontrolled thyroid disease Mothers with multiple fetuses (e.g., twins, triplets, etc.)

Ages Eligible for Study
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Minimum Age: 16 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: cholecalciferol-400 IU<br>Control group receiving 400 IU/day plus 0 IU vitamin D3 as placebo/day | Drug: cholecalciferol (vitamin D3)<br>* randomized control trial of three vitamin D doses: 400, 2000 and 4000 IU/day<br>Drug: cholecalciferol<br>* comparing vitamin D requirements of pregnant women and their fetuses from 12 weeks' gestation through pregnancy<br>* Other names: vitamin D3;|
| Experimental: cholecalciferol 2000 IU<br>Experimental group receiving 2000 IU total vitamin D3/day. | Drug: cholecalciferol (vitamin D3)<br>* randomized control trial of three vitamin D doses: 400, 2000 and 4000 IU/day<br>Drug: cholecalciferol<br>* comparing vitamin D requirements of pregnant women and their fetuses from 12 weeks' gestation through pregnancy<br>* Other names: vitamin D3;|
| Experimental: cholecalciferol 4000 IU<br>Experimental group receiving 4000 IU/day cholecalciferol | Drug: cholecalciferol (vitamin D3)<br>* randomized control trial of three vitamin D doses: 400, 2000 and 4000 IU/day<br>Drug: cholecalciferol<br>* comparing vitamin D requirements of pregnant women and their fetuses from 12 weeks' gestation through pregnancy<br>* Other names: vitamin D3;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 25-Hydroxyvitamin D Concentration | Circulating total 25(OH)D concentration measured in serum at visit 7, one month prior to delivery | 7 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vitamin D, cholecalciferol, pregnancy, bone mineral density