Your Prenatal Vitamin Primer

Multi-nutrient supplementation is recommended for women who are even considering pregnancy to cover the increased nutrient needs. When shopping for a vitamin, be sure to look for folic acid, calcium, copper, iron, zinc, and vitamins B-6, C, and D.

When looking for good vitamin, discuss with your doctor the right mix of nutrients for you. And remember that more isn't always better. In a study of over 22,000 pregnant women, those who took supplements with more than 10,000 international units (IU) a day of pre-formed vitamin A (retinol) were almost five times more likely to give birth to a baby with a birth defect than women who consumed 5,000 IU or less. A good vitamin A alternative is beta-carotene, which the body will convert into vitamin only if needed. (These days, many supplements have beta-carotene added to their formulae; look for it listed under vitamin A activity.)

A question that perplexes many moms-to-be is what is the difference between over-the-counter prenatal vitamins and prescription prenatal vitamins, or even between different brands?

The studies that have revealed the benefit of folic acid in decreasing the chance of miscarriage and organ abnormalities have shown that the minimum dosage to acquire this added protection is 400 mcg a day. Over-the-counter vitamins usually have this 400 mcg dose, and increasingly, over-the-counter prenatals have up to 800 mcg, but prescription vitamins have a full 1000 mcg (1 mg). So the advantage of the prescription vitamins is more than enough folic acid. These also have more iron, as well as formula mixes of other vitamins that have been tested extensively by large corporations that have spent a lot of money to ensure a safe product. Because the dosages are larger, and therefore prescription, they also have to deal with extra FDA scrutiny.

They may have a higher price tag because of that, too, but bear in mind that if you have a good health insurance plan with prescription coverage, it may actually cost you less to pay the co-pay on a prescription than the retail price of the over-the-counter prenatal at the store.

The problem with the prescription brands is that because they're big-gun vitamins, some women have trouble tolerating them (due to nausea, constipation, etc.). So sometimes it's better for a woman's nutrition to use the non-prescription vitamins until the side effects subside to the point where she can try a different brand of prescription vitamin, says Dr. Gerald DiLeo, MD, a board-certified OB-GYN who has served as chief of the medical staff at Lakeview Regional Medical Center in greater New Orleans. Not all brand-name prescription vitamins will be tolerated the same, but there should be one that works for everyone. Don't give up on them all because you can't tolerate a particular one.

If you find you really cannot tolerate the high-dose vitamins, or your doctor recommends it, then choose an over-the-counter prenatal multivitamin with 600 to 800 mcg of folic acid and some iron. Dr. DiLeo prefers big-company brands over "health food concoctions" for the assurance you get that the balance of nutrients will be appropriate. (For example, he says, "Too much vitamin A can affect the growth of the baby. Too much iron can deposit iron in other organs of a woman's body. These are the things that the big companies have worked out with billions of dollars' worth of research.")