Nutritional Requirements for Vitamin D in Pregnant Women

Not Applicable

Completed

• Conditions: Vitamin D Deficiency
• Interventions: Dietary Supplement: 10 mcg Vitamin D3; Dietary Supplement: 20 mcg Vitamin D3; Dietary Supplement: Placebo

• Registration Number: NCT02506439
• Lead Sponsor: University College Cork

Brief Summary

Randomised, placebo-controlled dose-response intervention study with vitamin D3 in pregnant women.

Detailed Description

This is a three-arm, parallel, double-blind, placebo-controlled dose-response intervention study with vitamin D3. Women will be recruited prior to 18 weeks of gestation and randomised to receive placebo, 10 or 20 mcg/d of vitamin D3 from baseline visit in their first trimester until delivery. Blood samples will be collected at baseline, midpoint and endpoint of the trial, at 10 week intervals, and from the umbilical cord at delivery. A 25-hydroxyvitamin D concentration of 30 nmol/L will be used to denote vitamin D deficiency. Information on maternal anthropometry, diet, lifestyle, sun exposure, blood pressure, iPTH and serum total calcium will also be reported.

Study Timeline

• Study Start: 2014-11-01
• Study First Submitted: 2015-05-12
• Study First Submitted QC: 2015-07-22
• Study First Posted: 2015-07-23
• Primary Completion: 2017-04-01
• Study Completion: 2017-04-01
• Status Verified: 2024-11
• Last Update Submitted: 2024-11-15
• Last Update Posted: 2024-11-19

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 144

Inclusion Criteria

• Adult (>18 years)
• No more than 18 weeks gestation
• In good general health
• Low risk pregnancy
• Not consuming >10 mcg/d vitamin D from supplements

Exclusion Criteria

• Current smokers
• Diagnosed hypertension
• Known high-risk pregnancy
• Diagnosed medical illness including diabetes mellitus (Types 1 & 2), chronic kidney disease or gastro-intestinal diseases or any illness known to interfere with calcium metabolism (e.g. sarcoidosis).
• Consumption of medications known to interfere with vitamin D metabolism
• Consumption of vitamin D (≥ 10 µg/day) or calcium (≥ 650 mg/d) supplements prior to randomization

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
10 mcg Vitamin D3	10 mcg Vitamin D3	White-skinned women will receive Cholecalciferol (Vitamin D3) 10 mcg \[400 IU\] daily
20 mcg Vitamin D3	20 mcg Vitamin D3	White-skinned women will receive Cholecalciferol (Vitamin D3) 20 mcg \[800 IU\] daily
Placebo	Placebo	White-skinned women will receive a Placebo supplement, identical in appearance and taste to the active product

Primary Outcome Measures

Name	Time	Method
Serum 25-hydroxyvitamin D in pregnant women and cord blood	Change from 1st through 2nd trimester and at delivery	Analysis of serum 25-hydroxyvitamin D in mothers for blood taken in the first, second and third trimesters and in umbilical cord

Secondary Outcome Measures

Name	Time	Method
Serum total calcium	Change from 1st through 2nd trimester and at delivery	Analysis of serum total calcium (adjusted for albumin) in mothers for blood taken in the first, second and third trimesters and in umbilical cord
Serum Parathyroid Hormone	Change from 1st through 2nd trimester and at delivery	Analysis of serum PTH in mothers for blood taken in the first, second and third trimesters and in umbilical cord

Trial Locations

Locations (2)

Cork University Maternity Hospital and University College Cork; 🇮🇪 Cork, Ireland

Human Nutrition Resource Unit, School of Food and Nutritional Sciences, University College Cork; 🇮🇪 Cork, Ireland