Vitamin D During Pregnancy Can Affect the Health of Mother and Child
In recent years, we have learned that sufficient blood levels of this vitamin are crucial to our health, and also that a significant proportion of the population, including pregnant women, is deficient. Vitamin D is an immune-supporting nutrient and during pregnancy, especially during the third trimester, it is a key factor in growth of the baby’s skeleton. It is estimated that up to 50% of pregnant women and breastfed infants are deficient in vitamin D, and deficiency is associated with pregnancy complications.1,2 For pregnant and nursing women, vitamin D deficiency or insufficiency has been associated with increased risk of preeclampsia, gestational diabetes, infections, and low birthweight. Vitamin D insufficiency during pregnancy is also associated with impaired growth during infancy, greater body fat mass and greater risk of low bone mass and autoimmune diseases during childhood.1,3-8
The American College of Obstetrics and Gynecology and Institute of Medicine both recommend that pregnant women take 600 IU/day supplemental vitamin D, and most prenatal vitamins, similar to other conventional multivitamins, contain 400 IU vitamin D. However, scientists have voiced concerns that these amounts are inadequate for most people to maintain blood 25(OH)D in the 30-45 ng/ml range, considered a sufficient vitamin D level.9
Clinical trials investigating vitamin D during pregnancy have reported that supplementation with either 2000 IU or 4000 IU doses of vitamin D improved maternal, cord blood, and neonatal 25(OH)D. Also, pregnancy complications, such as hypertension, infection and preterm birth, were less common in the women who achieved higher 25(OH)D. Importantly, women with higher 25(OH)D gave birth to babies with higher 25(OH)D, confirming that the supplementation helped to insure that babies were born with sufficient vitamin D levels.4,10,11
As part of the nutritional plan for a healthy pregnancy and a healthy start for the baby, pregnant women should supplement to achieve 25(OH)D levels in the 30-45 ng/ml range. The amount of supplementation necessary for individuals to reach optimal serum 25(OH)D levels may vary; vitamin D needs should be assessed by blood test and supplementation adjusted accordingly. For some women that may be 1000-2000 IU, but others may require more or less.
1. Mulligan ML, Felton SK, Riek AE, et al: Implications of vitamin D deficiency in pregnancy and lactation. Am J Obstet Gynecol 2010, 202:429 e421-429.
2. Barrett H, McElduff A: Vitamin D and pregnancy: An old problem revisited. Best Pract Res Clin Endocrinol Metab 2010, 24:527-539.
3. Urrutia RP, Thorp JM: Vitamin D in pregnancy: current concepts. Curr Opin Obstet Gynecol 2012, 24:57-64.
4. Wagner CL, Taylor SN, Dawodu A, et al: Vitamin D and its role during pregnancy in attaining optimal health of mother and fetus. Nutrients 2012, 4:208-230.
5. Crozier SR, Harvey NC, Inskip HM, et al: Maternal vitamin D status in pregnancy is associated with adiposity in the offspring: findings from the Southampton Women's Survey. Am J Clin Nutr 2012.
6. Gernand AD, Simhan HN, Klebanoff MA, et al: Maternal serum 25-hydroxyvitamin D and measures of newborn and placental weight in a U.S. multicenter cohort study. J Clin Endocrinol Metab 2013, 98:398-404.
7. Zhu K, Whitehouse AJ, Hart PH, et al: Maternal vitamin d status during pregnancy and bone mass in offspring at 20 years of age: a prospective cohort study. J Bone Miner Res 2014, 29:1088-1095.
8. De-Regil LM, Palacios C, Ansary A, et al: Vitamin D supplementation for women during pregnancy. Cochrane Database Syst Rev 2012, 2:CD008873.
9. Bischoff-Ferrari HA, Willett W: Comment on the IOM Vitamin D and Calcium Recommendations. In Harvard School of Public Health: The Nutrition Source; 2010.
10. Wagner CL, McNeil RB, Johnson DD, et al: Health characteristics and outcomes of two randomized vitamin D supplementation trials during pregnancy: a combined analysis. J Steroid Biochem Mol Biol 2013, 136:313-320.
11. Smith M: PAS: Vitamin D Cuts Risks of Pregnancy. In MedPage Today; 2010.