Pregnant women should only take vitamin supplements on a health care provider's recommendation. A healthy diet is the best way to receive nutrients, but vitamin supplements may provide an important benefit. It is important to remember that vitamin supplements work best when taken as part of a healthy diet and not as a substitute for a healthy diet.

Current research has shown that it is important for women who are planning to become pregnant (and those who are currently pregnant) to consume at least 400 mcg of folic acid per day. If a mother does not have adequate intake of folic acid within the first few months of pregnancy, the fetus is at risk of developing neural tube defects (such as spina bifida). Studies show that taking at least 400 mcg of folic acid can reduce the risk of these birth defects by as much as 70%.

Iron is also important during pregnancy. The National Academy of Sciences recommends that all pregnant women eat a healthy balanced diet and take an iron supplement providing 30 mg of iron during the second and third trimesters of pregnancy.

Research has also shown that essential fatty acids, specifically docosahexaenoic acid (DHA), are critical for developing babies. While the requirements during pregnancy have not been established, they likely exceed that of a non-pregnant female. Most pregnant women likely do not get enough omega-3 fatty acids because the major dietary source, seafood, is restricted during pregnancy. For pregnant women to obtain adequate omega-3 fatty acids, a variety of dietary sources, that may include a fish oil supplement, may be necessary.

Eating right during pregnancy is one of the best things you can do for yourself and your baby. Supplements may provide an important benefit, but their use should be discussed with your healthcare provider.