Final answer:
Prenatal supplements containing folic acid are essential in preventing neural tube defects such as spina bifida and anencephaly, with a recommended daily intake of at least 400 µg/day.
Step-by-step explanation:
Prenatal supplements, particularly those containing folic acid, are often recommended to pregnant women to support fetal health. A key benefit of these supplements is the prevention of neural tube defects like spina bifida and anencephaly. Folic acid plays a crucial role during the early stages of pregnancy, and a deficiency in maternal folate can lead to these severe birth defects. Therefore, the National Institutes of Health and other health organizations recommend a daily intake of at least 400 µg/day of folate from supplements or fortified foods for women who may become pregnant. This intake is important because it significantly reduces the risk of neural tube defects, enhancing the prospect of a healthy pregnancy and fetal development.