Safety and Toxicity of Vitamin A Supplements in Pregnancy

Abstract

Vitamin A plays an essential role during fetal development; however, if consumed at high doses it can produce teratogenic effects. Synthetic retinoids are potent teratogens and are contraindicated during pregnancy. β-Carotene is free of toxic effects. Intakes of vitamin A less than 10,000 IU per day during pregnancy have not been associated with birth defects. However, there are conflicting results for intakes of 10,000 IU to 30,000 IU per day. Intakes of vitamin A greater than 10,000 IU per day are not recommended for well-nourished pregnant women. Intakes of 30,000 IU per day of vitamin A in nonpregnant women produce only minor increases in the primary teratogen of vitamin A embryopathy. in vitamin A–deficient populations, doses of vitamin A less than 10,000 IU per day or 25,000 IU per week are considered beneficial to pregnant women without risk to the fetus. in these populations, the risks of teratogenicity from high vitamin A intake may need to be balanced against those from a deficiency.