Updated January 26, 2014.

What:
Iron, 27 mg, elemental

Why:
Iron helps your red blood cells carry oxygen to your body.

Where to find it:
liver, tofu, beans, oatmeal

When you need a supplement:
Many pregnant women will need supplemental iron. A typical prenatal vitamin will have iron included. This can be plenty for most women, though some may still become anemic. If you require additional supplements, you may also consider liquid vitamins to increase iron absorption.

Other:
Iron supplementation can lead to constipation, stomach upset and other digestive issues.