Trial to Assess Vitamin D Requirements in Lactating Women

Study Overview
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Brief Summary
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This is a randomized, placebo-controlled trial of vitamin D supplementation with 20mcg cholecalciferol (to achieve a total intake of 25mcg/day), with or without 500mg calcium to assess vitamin D requirements in lactating women and to ascertain whether vitamin D supplementation at levels sufficient to achieve defined thresholds of maternal serum 25-hydroxyvitamin D will increase the vitamin D content of maternal milk. The study will also report serum 25-hydroxyvitamin D in maternal-cord dyads over a 12-month period and describe the relationship between them. Information on maternal iPTH levels, anthropometry, diet and sun exposure will also be reported.

Official Title
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Randomised Placebo-controlled Supplementation Study With Vitamin D and Calcium in Breastfeeding Mothers

Conditions
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Vitamin D Deficiency, Vitamin D Insufficiency

Intervention / Treatment
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* Dietary Supplement: 20µg Vitamin D3
* Dietary Supplement: 20µg Vitamin D3 + 500 mg Calcium
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Pregnant women intending to breast feed their infant for at least 12-weeks Pregnant women >20 weeks gestation Pregnant women >18 years of age Pregnant women in good general health Exclusion Criteria: Consumption of a vitamin D-containing supplement(>10µg/day) in the 3 months prior to commencing the trial Consumption of a vitamin D or calcium containing supplement during the 12- week trial Mothers taking a vacation to a sunny climate or using a solarium during the 12-week trial Mothers with pre-existing type 1 or type 2 diabetes Mothers with pre-existing hypertension Mothers with diagnosed hypercalcemia Mothers with diagnosed intestinal malabsorption conditions Mothers with multiple fetuses (e.g. twins) Consumption of medications known to interfere with vitamin D metabolism.

Ages Eligible for Study
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Minimum Age: 18 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 20µg Vitamin D3<br>Arm will receive per day one gelatin capsule containing 20µg (800IU) of vitamin D3 (Cholecalciferol). | Dietary Supplement: 20µg Vitamin D3<br>* 20µg (800IU) of vitamin D3/day for 12-weeks while lactating, commencing 10-14 days post-partum.<br>* Other names: Cholecalciferol;|
| Active Comparator: 20µg Vitamin D3 + 500 mg Calcium<br>Arm will receive per day one gelatin capsule containing 20µg (800IU) of vitamin D3 (Cholecalciferol) and one tablet of calcium carbonate containing 500mg of calcium. | Dietary Supplement: 20µg Vitamin D3 + 500 mg Calcium<br>* 20µg (800IU) of vitamin D3 + 500mg calcium carbonate/day for 12-weeks while lactating, commencing 10-14 days post-partum.<br>* Other names: Cholecalciferol and Calcium;|
| Placebo Comparator: Placebo<br>Arm will receive one gelatin capsule containing 0µg (0IU) of vitamin D3 (Cholecalciferol). | Dietary Supplement: Placebo<br>* One gelatin placebo capsule containing zero vitamin D3 taken for 12-weeks while lactating, commencing 10-14 days post-partum.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum 25-hydroxyvitamin D in mothers and levels of vitamin D in maternal milk | Baseline and endpoint serum 25(OH)D analysis in mothers (week 0 and week 12); baseline, week 4, week 8 and enpoint analysis of vitamin D3, D2 and 25(OH)D in expressed breast milk (hindmilk samples) | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maternal serum iPTH | Baseline and endpoint PTH will be measured in mothers | 12 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Lactation, Vitamin D, Cholecalciferol, Nutrient requirements, Randomised Controlled Trial, pregnancy, Cord blood, Human milk, serum 25-hydroxyvitamin D, deficiency, insufficiency, nutrition