If you're pregnant, you're at increased risk of iron deficiency anemia. Iron deficiency anemia is a condition in which you don't have enough healthy red blood cells to carry adequate oxygen to the body's tissues. Find out why anemia during pregnancy occurs and what you can do to prevent it.

Your body uses iron to make hemoglobin. Hemoglobin is a protein in the red blood cells that carries oxygen to your tissues. During pregnancy, the volume of blood in your body increases, and so does the amount of iron you need. Your body uses iron to make more blood to supply oxygen to your baby. If you don't have enough iron stores or get enough iron during pregnancy, you could develop iron deficiency anemia.

Severe iron deficiency anemia during pregnancy increases the risk of premature birth (when delivery occurs before 37 complete weeks of pregnancy). Iron deficiency anemia during pregnancy is also associated with having a low birth weight baby and postpartum depression. Some studies also show an increased risk of infant death immediately before or after birth.

You are at increased risk of developing anemia during pregnancy if you:

• Have two closely spaced pregnancies
• Are pregnant with more than one baby
• Are vomiting frequently due to morning sickness
• Don't consume enough iron-rich foods
• Have a heavy pre-pregnancy menstrual flow
• Have a history of anemia before your pregnancy

Anemia signs and symptoms include:

• Fatigue
• Weakness
• Dizziness or lightheadedness
• Headache
• Pale or yellowish skin
• Shortness of breath
• Craving or chewing ice (pica)

Symptoms of severe anemia may include:

• A rapid heartbeat
• Low blood pressure
• Difficulty concentrating

Keep in mind, however, that symptoms of anemia are often similar to general pregnancy symptoms. Regardless of whether or not you have symptoms, you'll have blood tests to screen for anemia during pregnancy. If you're concerned about your level of fatigue or any other symptoms, talk to your health care provider.

Prenatal vitamins typically contain iron. Taking a prenatal vitamin that contains iron can help prevent and treat iron deficiency anemia during pregnancy. In some cases, your health care provider might recommend a separate iron supplement. During pregnancy, you need 27 milligrams of iron a day.

Good nutrition can also prevent iron deficiency anemia during pregnancy. Dietary sources of iron include lean red meat, poultry and fish. Other options include iron-fortified breakfast cereals, dark green leafy vegetables, dried beans and peas.

The iron from animal products, such as meat, is most easily absorbed. To enhance the absorption of iron from plant sources and supplements, pair them with a food or drink high in vitamin C — such as orange juice, tomato juice or strawberries. If you take iron supplements with orange juice, avoid the calcium-fortified variety. Although calcium is an essential nutrient during pregnancy, calcium can decrease iron absorption.

If you are taking a prenatal vitamin that contains iron and you are anemic, your health care provider might recommend testing to determine other possible causes. In some cases, you might need to see a doctor who specializes in treating blood disorders (hematologist). If the cause is iron deficiency, your health care provider may recommend additional supplemental iron. If you have a history of gastric bypass or small bowel surgery or are unable to tolerate oral iron supplementation, you might need to have iron administered through a needle placed into one of your veins (intravenous administration).