Are there any vitamins I should not take during pregnancy?

    During pregnancy, the vitamin that should be avoided in excess quantities is supplemental Vitamin A. There are foods that include Vitamin A as part of the enrichment process and thus the food labels need to be read before eating enriched foods.

    Vitamin A in large doses as a supplement has been shown to have a potentially negative effect on fetal development. Carrots and vegetables, on the other hand, do not contain vitamin A itself but carotene. Carotene is provitamin A and is converted to vitamin A in your body only if your body needs it. You cannot get too much Vitamin A by eating Carotene because the body regulates conversion from carotene to Vitamin A. Although carotene is converted to vitamin A in the body, excessive ingestion of carotene causes carotenemia, not vitamin A toxicity.

    Liver and other meats do contain vitamin A, so by eating those you could ingest a larger amount of vitamin A. Eating carrots and vegetables cannot do any harm to your baby.

    Other vitamins that could cause a problem due to build up in the body are Vitamins D, E and K.

    When supplemental Vitamin A is added to the prenatal vitamin, overdose can occur in as little as 4 times the regular dose. If Vitamin A is consumed in amounts greater than 10,000 IUs, liver toxicity or fetal birth defects can occur. Vitamin A is consumed in common foods like meat, fish and eggs. Fortified cereals also add Vitamin A. This means it is relatively easy to reach that upper level without trying to.

    Vitamin D and toxicity is a heavily studied topic. The upper level of Vitamin D supplementation is set at 2,000 IUs a day. The human body can produce 20,000 IUs of Vitamin D if exposed to the sun without clothing in one shot. Herein lies the trouble with supplementation. Vitamin D toxicity does occur, but due to the overwhelming conflict in studies, Vitamin D supplementation is not recommended in pregnant women.

    Vitamin E supplementation is just as tricky as Vitamin D supplementation. There are two forms of Vitamin E supplements, synthetic and natural. Natural vitamin E is more readily absorbed by the body, but most supplements contain the synthetic version. There is a link between babies with heart defects and supplemental Vitamin E. In a recent study, women who took supplemental Vitamin E (over and above their prenatal vitamin) were 70% more likely to give birth to a baby with a heart defect.

    Too much Vitamin K is associated with babies having worse cases of jaundice. Jaundice is a yellowing of the skin due to a buildup of bilirubin in the body.