If you are pregnant or trying to become pregnant, Vitamin D is probably not one of your main health concerns. Very few studies exist that show the effects of high or low vitamin D levels on pregnancy, so it is not one of the vitamins that doctors urge women to take during gestation. The main source of Vitamin D is from the sun. The only other very reliable source of Vitamin D is through a dietary supplement, as few foods are actually high in the vitamin. In adults and children, the main concern with Vitamin D deficiency is soft bones. However, for unborn babies, the deficiency of Vitamin D in their mothers has been linked to other negative side effects.
While few studies exist to explore the effects of Vitamin D deficiency in babies during pregnancy, some negative outcomes have been linked with it. It has been correlated with a greater likelihood of cesarean delivery, bacterial vaginitis, less efficient glucose metabolism and preeclampsia. These side effects are not definitely a result of Vitamin D deficiency, but pregnant women should consider taking a dietary supplement to prevent them just in case. Dietary supplements that contain Vitamin D can be purchased over the counter, and they have no negative side effects that will affect you as a pregnant woman.
Increasing your Vitamin D intake without a dietary supplement can be difficult, as it puts you at risk for other problems. Sunscreen prevents Vitamin D from being absorbed by the skin in the sun, but not wearing sunscreen obviously puts you at risk for skin cancer. Similarly, covering your skin in the sun and living in areas with less sun exposure inhibit the absorption of Vitamin D, but both also protect you from cancer. So, taking supplements is a slightly safer way to make sure your body is not Vitamin D deficient.
Vitamin D is difficult to absorb, which is why it is normally paired with other vitamins and minerals in order to make sure it is absorbed properly. That’s why you should speak with your doctor about how to safely take the supplement before adding it to your vitamin regimen.
Source: C A Mcgowen et al: Insufficient Vitamin D Intakes Among Pregnant Women. European Journal of Clinical Nutrition Volume 65 September 2011