Your Prenatal Vitamin Primer

Registered Nurse Marie O'Sullivan compared five brands of prenatal vitamins, and reports that, indeed, the dose of each vitamin varies from brand to brand, with all doctor-prescribed brands having 1000 mcg (1 mg) of folic acid, the vitamin to be most concerned about. Over-the-counter brands have between 400 and 800 mcg, she confirms. The other big difference she found is the form in which the vitamin is offered. Some prenatal vitamins come in a chewable or liquid form. The liquid is especially helpful if you are nauseated. You can add the dose into your orange juice and drink it (slowly), O'Sullivan suggests.

Is there a male version of the prenatal vitamin for when we're trying to conceive?

They don't make prenatal vitamins for men (at least not yet!), but the diet and lifestyle choices the would-be father makes may affect your chances for conception. Check out The Fertility Diet for Him.

Do overweight women need a higher-dose vitamin?

Research led by Dr. Martha M. Werler, DSc, an epidemiologist at Boston University, suggests that typical prenatal vitamins don't contain enough folic acid to provide protection against neural tube defects in the babies of overweight women. Dr. Werler found that while at least 400 mcg of folic acid a day reduced the risk of neural-tube defects by 40 percent for children of women weighing less than 154 pounds, this dose did not reduce the risk in heavier women. As a result, some physicians believe plus-size women should take additional folic acid supplements along with their prenatal vitamins to obtain full protection. Ask your physician whether a higher dose of folic acid is right for you.

If I eat a healthy diet, do I really need to supplement?

The discovery of folic acid's role in the reduction of neural tube defects led to the fortification of many commercially-produced foods (breads, pasta, and cereals) with the vitamin. According to the Centers for Disease Control (CDC), this fortification led to a 25 percent decrease in neural tube defects in the overall population. So, indeed, many women who eat healthy diets rich in folic acid (including dark green leafy vegetables, nuts, or fortified cereals) ask why they need the supplement. The answer is that the synthetic form of folic acid seems to be more effective for this type of protection, and pregnant women require twice the amount of folic acid that non-pregnant women require.

According to the March of Dimes, during the last six months of pregnancy and breastfeeding, your body will absorb more calcium from food than when you are not pregnant. In turn, your baby is absorbing this extra calcium from you to build strong teeth and bones. Many women do not get sufficient calcium in their diet. If you don't get enough calcium during pregnancy, your baby's calcium needs will be supplied from the calcium stored in your bones, thus weakening your bones. So calcium supplementation can help while you pursue a calcium-rich diet.

Both you and your fetus also need additional amounts of iron during pregnancy. Iron is important for building your blood supply, and your baby needs it to stockpile for future use. Since human milk and cow's milk are both low in iron, your baby will be able to draw upon a banked supply for the first three to six months of his life. For this reason, 30 to 60 mg of supplemental iron (typical quantities for prenatal supplements) are recommended during pregnancy. Excellent dietary sources of iron are dried fruits, spinach, liver, dark green leafy vegetables, and sardines.