Vitamin D deficiency is thought to be common among pregnant women, and has been found to be associated with an increased risk of pre-eclampsia, gestational diabetes, preterm birth, and other tissue-specific conditions.
In general, normal pregnancy is associated with insulin resistance. Insulin resistance is a condition in which muscle, fat, and liver cells do not respond properly to insulin, and therefore can’t easily absorb glucose from the bloodstream. As a result, the body needs higher levels of insulin to help glucose enter cells.
However, insulin resistance is much worse in pregnant women with gestational diabetes, a condition that affects 10% of pregnancies. No one knows why pregnancy is associated with insulin resistance. Gestational diabetes usually, but not always, disappears after the pregnancy is over.
How Much Is Enough?
Vitamin D recommendations for pregnant women vary vastly depending on which source you read. The vitamin D council recommends 4,000-6,000 international units (IU) per day for pregnant women. The Food and Drug Administration recommends 600 IU per day.
Please consult with your health care provider about taking vitamin D during pregnancy and how much is recommended.
In Health and Happiness,
Kelly Harrington, MS, RDN
Registered Dietitian Nutritionist for Healthy Goods
1. Maghbooli Z, at al. Correlation between vitamin D3 deficiency and insulin resistance in pregnancy. Diabetes Metab Res Rev. 2008 Jan-Feb;24(1):27-32. http://www.ncbi.nlm.nih.gov/pubmed/17607661
2. Soheilykhah S, et al. The effect of different doses of vitamin D supplementation on insulin resistance during pregnancy. Gynecol Endocrinol. 2013 Apr;29(4):396-9. http://www.ncbi.nlm.nih.gov/pubmed/23350644