Throughout the life of a woman, her body is constantly confronted with so many challenges that demand complex physiological changes. Perhaps, the toughest physical challenge that a woman has to face in her lifetime is the task of procreation – pregnancy.

Pregnancy induces a lot of physiological changes in the woman’s body and all of them have to occur in order to support the growth of a new life that is present inside her. One remarkable change is on how a woman’s blood, the life-maintaining fluid of the fetus, increases its volume to about 40 to 45 % during pregnancy. This is an essential physiological change that has to occur because more blood is needed to circulate through the heart, arteries, veins, and other tissues of the body to carry waste and carbon dioxide not only from the mother, but also from the baby. Likewise, more blood is also needed to bring nourishment, electrolytes, hormones, vitamins, antibodies, heat, and oxygen to the tissues not only to the mother, but also to the baby.

Apparently, this increase in the maternal blood volume does not come for free. Production of new blood cells requires some elements which are mostly derived from the maternal diet. Low levels of these elements (e.g. iron, folic acid, vitamin B12) can lead to less red blood cell production or a lowered ability of red blood cells to carry oxygen or iron, a condition known as anemia. Anemia can cause poor fetal growth, low birth weight, and preterm birth.

There are several causes of anemia. Fortunately, the most common ones are preventable.

1. Iron Deficiency Anemia
This is the most common cause of anemia in pregnancy. Iron is necessary to make hemoglobin – the part of the red blood cell which carries oxygen to the tissues. Approximately 1000 mg of iron is needed during pregnancy. If the mother does not have sufficient iron stores, anemia develops. The key to prevent this is to have adequate iron stores before becoming pregnant, by eating iron-rich foods such as the following: meats (beef, pork, chicken, organ meats), shellfish, legumes, green leafs of cabbage family, iron-enriched pasta, and cereals. During pregnancy, iron supplements should also be taken by the mother to ensure adequate iron supply.

2. Vitamin B12 Deficiency
Vitamin B12 is necessary for the formation of new red blood cells. Sources of vitamin B12 are animal foods like meat, poultry, eggs, and milk. Hence, people who are mostly affected by this type of anemia are the strict vegetarians who do not eat animal products. Pregnant women who are strict vegans should receive supplemental vitamin B12 injection during pregnancy.

3. Folate/Folic Acid Deficiency
Folic acid helps in the growth of new red blood cells. Like Vitamin B12 deficiency, a deficiency in folate will result to the formation of abnormally large red blood cells (megaloblastic anemia). Aside from anemia, folate deficiency can also increase the risk of having a baby with brain and spinal cord defects. In order to prevent this, it is now recommended that all women of childbearing age and during pregnancy should take 400 µg of folic acid supplement everyday. Food sources of folic acid are similar to those that have high iron content.

4. Blood Loss
Excessive blood loss during delivery can cause anemia. A woman can normally lose 500 milliliters of blood during a vaginal birth, and about 1000 milliliters with a cesarean delivery. The management depends on the amount of blood loss and the condition of the patient. Adequate iron stores can help replace the lost red blood cells but sometimes, transfusion is necessary.

Anemia is diagnosed through a routine blood test for blood hemoglobin (less than 11 mg/dl in the 1st and 3rd trimester and less than 10.5 mg//dl in the 2nd trimester) and hematocrit during prenatal check-up.

The presenting symptoms of anemia of pregnancy can vary. Some women may not have obvious symptoms at all unless their blood count is extremely low. These signs and symptoms to watch out for include: fatigue; pale lips and inner side of the eyelids, skin, and nails; rapid heartbeat; labored breathing; and dizziness. Always consult your obstetrician if you have any of these symptoms. It is important to seek professional help and not to self-medicate, because the treatment will depend on the cause and severity of the anemia, for which only your physician can determine.