Vitamin D Supplementation of Lactating Mothers

Study Overview
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Brief Summary
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The investigators would like to test the hypothesis that maternal vitamin D supplementation during lactation in dose 1200IU/d (400IU from multivitamins + 800 IU cholecalciferol) is more effective than 400IU/d (400IU from multivitamins + placebo)to built appropriate maternal vitamin D status and could be beneficial for maternal and infants bone mineralization and body composition (proper proportion of muscle and fat tissues in body weight) and is safe for both. The investigators also want to confirm that vitamin D supplementation of exclusively breastfed infants in dose 400IU/d is adequate to build appropriate vitamin D status independently of mother's vitamin D supplementation up to 1200 ID/d. Additionally the investigators hypothesize that because of changes in lifestyle there will be no substantial seasonal differences in vitamin D status of pregnant women at the delivery and their newborn infants.

Official Title
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Effect of Vitamin D Supplementation During Lactation on Vitamin D Status, Bone Mineralisation and Body Composition of Mother and Their Exclusively Breastfed Infants.

Conditions
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Vitamin D Deficiency

Intervention / Treatment
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* Dietary Supplement: cholecalciferol
* Dietary Supplement: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy women without major medical problem delivered at term and planning breastfeeding for next six months delivering term, single, infants with birth weight appropriate for gestational age without major health problem Exclusion Criteria: Maternal endocrine disorders, disturbed calcium- phosphorus homeostasis, anticonvulsant treatment. Infants renal, hepatic insufficiency, endocrine disorders, congenital malformations, anticonvulsant treatment.
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 |
| --- | --- |
| Experimental: choecalciferol<br> | Dietary Supplement: cholecalciferol<br>* dose 800 IU/day for 6 month<br>* Other names: vit D;|
| Placebo Comparator: placebo<br> | Dietary Supplement: placebo<br>* oil capsules<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| serum 25-hydroxyvitamin D concentration, |  | 3 time poits up to 6 months (0-3-6 months) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| body composition measured by dual x-ray densitometry |  | 3 time points up to 6 months (0-3-6months) | 
| serum calcium |  | 2 time poits up to 6 months ( 3-6 months) | 
| calciuria (Urinary calcium and creatinine - UCa/crea) |  | 2 time poits up to 6 months ( 3-6 months) | 
| iPTH |  | 3 time poits up to 6 months (0-3-6 months) | 
| Prevalence of vitamin D deficiency (25OHD<20ng/ml) |  | 3 time poits up to 6 months (0-3-6 months) | 
| Prevalence of vitamin D sufficiency (25OHD>30ng/ml) |  | 3 time poits up to 6 months (0-3-6 months) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vitamin D, vitamin D deficiency, breastfeeding, body composition, bone mineral content