Iron deficiency is the most common nutritional deficiency during pregnancy, causing anemia in half of all pregnant women. Iron deficiency anemia can cause fatigue, weakness and shortness of breath. In pregnancy, it increases the risk of preterm delivery, low birth weight and postpartum complications.

Iron is necessary for healthy red blood cells. It's needed to make hemoglobin, a substance that helps your blood cells carry oxygen to your tissues. Iron requirements increase during pregnancy because pregnant mothers, as well as their growing babies, need extra blood cells.

If you're pregnant, you're likely to have at least two blood tests that check for anemia. The first occurs early in pregnancy, along with a battery of initial blood tests. The second occurs close to 28 weeks gestation, at the same time the gestational diabetes test is done. If you're found to be anemic, it's important to eat iron-rich foods and begin daily iron supplements as advised by your health provider. This will help you boost your energy during pregnancy and lower your risk of complications.

Dietary iron comes in two forms: heme iron and non-heme iron.

Heme iron is well absorbed by your body and is found in animal products. Sources include lean red meats, shrimp and other seafood, turkey, egg yolks and liver. (Caution: liver should eaten only occasionally during pregnancy to prevent excessive Vitamin A intake, which can be harmful to a growing baby.)

Non-heme iron is found in vegetables and grains and is less well absorbed by your body. This is why vegetarians are at greater risk for iron deficiency. Important sources of non-heme iron include enriched breakfast cereals; wheat germ; cooked beans; nuts (almonds, cashews); peanut butter; dried fruits (prunes, apricots, figs, raisins, peaches and dates); seeds; dark green or yellow vegetables (collard greens, kale, mustard greens, spinach), and blackstrap molasses.

Your body may not absorb all the iron that is available in foods, as certain products enhance or impair iron absorption. Foods containing Vitamin C, such as orange juice or tomato juice, will improve iron absorption. Milk, calcium and Tums®, along with black and green tea, inhibit iron absorption. Ideally, none of these should be consumed within two hours of ingesting an iron supplement.

If you already have anemia, it's difficult to build up your iron stores with diet alone. Most health providers recommend a daily iron supplement, such as ferrous sulfate. If you look at the dosage of iron on the label, it may seem like these provide large amounts. However, only a fraction of oral iron supplements are absorbed. The rest is excreted through your intestines. This is why iron may cause your stools to appear firmer and darker in color. Eating fruits, vegetables and other high-fiber foods can help minimize constipation from iron supplements. Some doctors recommend taking a stool softener as well. It's also important to drink six to eight glasses of water a day.

To summarize, if you have iron deficiency anemia you should:

• Eat plenty of iron-rich foods
• Take iron supplements with Vitamin C or foods high in Vitamin C
• Avoid taking iron supplements with dairy products, calcium or non-herbal teas
• Enjoy plenty of water as well as fruits, vegetables and other high fiber items

Iron deficiency takes time to correct, and it's likely that you'll need to take iron throughout your pregnancy. But treating anemia will help you maintain your energy and feel your best during pregnancy.