In addition to the number of health benefits that have been linked to vitamin D, it now appears that the sunshine vitamin may play a significant role in the health of pregnant women and their babies, especially for their bones and immune systems.

The situation is complicated by the fact that most people do not get what are considered adequate amounts of vitamin D on a regular basis, either through diet or exposure to the sun. When a woman is pregnant, her baby may be adversely affected by these deficiencies.

In order to gain a better understanding of this phenomenon and to determine the optimal, yet safe, dose of vitamin D for both mother and baby, researchers gathered nearly 500 women who were 12-16 weeks into their pregnancies. They then divided them into three groups. One group received 400 International Units (IU) of vitamin D each day; the second group received 2000 IU; and a third group was given 4000 IU. The vitamins were administered until the day of delivery. Monthly check-ups were undertaken to ensure the safety of the subjects, and no adverse consequences were observed in any of the groups.

What they found was that vitamin D supplementation did have a positive influence on pregnancy, especially in lowering the rate of complications such as preeclampsia, gestational diabetes, infections, and preterm labor and delivery. The most benefits were seen in the women taking the highest doses, or 4000 IU per day. Consequently, some doctors are calling for revisions to the dietary guidelines for vitamin D and pregnant women, which currently recommend between 200 IU and 400 IU of vitamin D (the amount in prenatal vitamins) each day.

The findings are in contrast to how vitamin D supplementation had previously been viewed by the medical establishment. For years, experts were concerned that high levels of vitamin D increased the chances of birth defects, but now there is a growing understanding of its importance for both mother and child.

In fact, studies have shown that women who take supplemental vitamin D during their pregnancy increase their baby’s chances of healthier bones as the child grows older. For the mothers, vitamin D is associated with greater bone strength and by extension, a lower risk for fractures stemming from the weakening of their bones over time.

Interestingly enough, despite the widespread assumption that calcium is the most important nutrient for maintaining the health of our bones, many experts believe that vitamin D is just as critical, and yet most people do not get enough of it in their diets.

Good sources of vitamin D, besides exposure to the sun, include some common foods such as egg yolks, fish, liver, and fortified milk. It is important to keep in mind that before drastically increasing your consumption of vitamin D, consult with your physician, especially if you are pregnant.

For more information about vitamin D and pregnancy, visit Baby Center. To learn more about vitamin D and your health, visit the homepage for the Vitamin D Council.