Vitamin D supplementation during pregnancy: Double-blind, randomized clinical trial of safety and effectiveness
Bruce W. Hollis, Donna Johnson, Thomas C. Hulsey, Myla D. Ebeling, Carol L. Wagner · Journal of Bone and Mineral Research (2011)
TL;DR
A study of pregnant women found that taking higher daily amounts of vitamin D was safe and helped more mothers reach target vitamin levels.
What they did
Researchers studied 494 pregnant women starting at 12 to 16 weeks of pregnancy, and 350 women finished the trial at delivery. The women took daily vitamin D3 at doses of 400, 2000, or 4000 IU until birth. Scientists tested blood levels of vitamin D in both mothers and their newborn babies.
What they found
Women in the 4000 IU group had the highest rates of reaching blood vitamin levels of 80 nmol/L or greater. Compared to the 400 IU group, women taking 4000 IU daily were 1.60 times as likely to reach that target level. The researchers found no safety differences between the groups and reported zero adverse events from the vitamin.
Why it matters
Studies suggest that daily vitamin D intake may help mothers maintain healthy nutrient levels during pregnancy. Food choices and nutrient sources are linked to blood vitamin concentrations in both parents and babies.
Limits
The abstract does not discuss study limits. Only 350 of the 494 enrolled women remained in the trial through delivery. This is general education, not medical advice.
Jargon explained
- 25(OH)D
- The main form of vitamin D circulating in blood that doctors use to measure vitamin levels.
- IU
- International units, a standard measurement used for amounts of vitamins.
- Relative risk
- A comparison number showing how likely an outcome is in one group compared to another group.
Read the original: https://doi.org/10.1002/jbmr.463
Full citation
Bruce W. Hollis, Donna Johnson, Thomas C. Hulsey, Myla D. Ebeling, Carol L. Wagner (2011). Vitamin D supplementation during pregnancy: Double-blind, randomized clinical trial of safety and effectiveness. Journal of Bone and Mineral Research. DOI: 10.1002/jbmr.463
Open access (green): https://www.ncbi.nlm.nih.gov/pmc/articles/3183324
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Educational information only, not medical or dietary advice. Consult a qualified health professional for personal nutrition guidance.