Anemia During Pregnancy

Anemia facts

*Anemia facts medical author: William C. Shiel Jr., MD, FACP, FACR

• Anemia is a medical condition in which the red blood cell count or hemoglobin is less than
  
  normal.
• For men, anemia is typically defined as hemoglobin level of less than 13.5 gram/100 ml and in women as hemoglobin of less than 12.0 gram/100 ml.
• Anemia is caused by either a decrease in production of red blood cells or hemoglobin, or an increase in loss or destruction of red blood cells.
• Some patients with anemia have no symptoms. Others may feel tired, easily fatigued, appear pale, a feeling of heart racing, short of breath, and/or worsening of heart problems.
• Anemia can be detected by a simple blood test called a complete blood cell count (CBC).
• The treatment of the anemia varies greatly and very much depends on the particular cause.

What is anemia?

Anemia is a medical condition in which the red blood cell count or hemoglobin is less than normal. The normal level of hemoglobin is generally different in males and females. For men, anemia is typically defined as hemoglobin level of less than 13.5 gram/100 ml and in women as hemoglobin of less than 12.0 gram/100 ml. These definitions may vary slightly depending on the source and the laboratory reference used

What causes anemia?

Any process that can disrupt the normal life span of a red blood cell may cause anemia. Normal life span of a red blood cell is typically around 120 days. Red blood cells are made in the bone marrow.

Anemia is caused essentially through two basic pathways. Anemia is caused by either:

1. a decrease in production of red blood cells or hemoglobin, or
2. an increase in loss or destruction of red blood cells.

A more common classification of anemia (low hemoglobin) is based on the Mean Corposcular Volume (MCV) which signifies the average volume of individual red blood cells.

1. If the MCV is low (less than 80), the anemia is categorized asmicrocytic anemia (low cell volume).
2. If the MCV is in the normal range (80-100), it is called a normocytic anemia (normal cell volume).
3. If the MCV is high, then it is called a macrocytic anemia (large cell volume).

Looking at each of the components of a complete blood count (CBC), especially the MCV, a physician can gather clues as to what could be the most common reason for anemia in each patient.

Anemia During Pregnancy

The wonder and joy of pregnancy is matched by the body's ability to adapt to looking after the growing baby. In addition to the mother's physiologic needs, there is the additional need to provide the building blocks to optimally grow baby. All this construction requires energy and oxygen as the fuel that helps drive the engine.

Oxygen in the air that we breathe is delivered to the cells of the body by hemoglobin, a protein molecule found in red blood cells. The normal ranges for hemoglobin depend on the age and, beginning in adolescence, the gender of the person. For example, the normal ranges of hemoglobins for background comparison are:

• Newborns: 17 to 22 gm/dl
• Babies 1 week of age: 15 to 20 gm/dl
• Babies 1 month of age: 11 to 15 gm/dl
• Children: 11 to 13 gm/dl
• Adult men: 14 to 18 gm/dl
• Adult women: 12 to 16 gm/dl
• Men after middle age: 12.4 to 14.9 gm/dl
• Women after middle age: 11.7 to 13.8 gm/dl

Anemia is a decrease in the amount of hemoglobin and red blood cells. Anemia is a relatively normal finding in pregnancy. Plasma is the watery, noncellular component of blood. In pregnancy, there is an increase in plasma volume of the blood in order to help supply oxygen and nutrients to mother and baby. There can be a 20% increase in the total number of red blood cells but the amount of plasma increases even more causing dilution of those red cells in the body. A hemoglobin level of pregnancy can naturally lower to 10.5 gm/dL representing a normal anemia of pregnancy.

Nevertheless, the body needs a minimum amount of hemoglobin to supply the oxygen needs of the body and if it is lacking, the symptoms of anemia may occur. Symptoms of anemia include feeling increasingly tired, weak,short of breath with activity or at rest, a rapid heart rate, and a pale appearance to the skin. Lightheadedness or dizziness may occur when standing up too quickly or trying to physically exert. Symptoms occur because the body's oxygen requirements cannot be met by a decreased amount of hemoglobin contained in the fewer number of red blood cells.

If the pregnant mother had heavy prepregnancy menstrual flow, she may be anemic entering the pregnancy and the normal physiology of carrying a growing baby may make the anemia more pronounced. If there are two pregnancies close together, the mother's body may not yet have recovered, increasing the chances for anemia. It also can be difficult getting enough nutrition and iron with morning sickness. And the risk of anemia in pregnancy is even greater with multiple pregnancies, such as twins or triplets.

Anemia in pregnancy is common, but it is also frequently preventable through optimal diet and nutrition. The key is loading up on foods that are high in iron content like dark green leafy vegetables, eggs, and meat. As well, many foods like cereals and bread are iron fortified. If that doesn't work the health care professional may suggest an iron supplement to help replenish the body's stores. But in addition to iron, the body needs other building blocks to help make red blood cells including folic acid, which is an important vitamin to take to prevent potential damage to the growing baby's brain and spinal cord (neural tube defects).

A mother's physiology usually adapts well to the needs of a growing baby. Eating wisely can help the body cope with the physiology changes that are required. Eating wisely can, as a result, prevent the tiredness and weakness that can often accompany anemia. Basically, a healthy mother makes a healthy baby.

Can anemia be hereditary?

Yes, anemia may be genetic. Hereditary disorders can shorten the life span of the red blood cell and lead to anemia (for example, sickle cell anemia). Hereditary disorders can also cause anemia by impairing the production of hemoglobin (for example, alpha thalassemia and beta thalassemia).

Depending on the degree of the genetic abnormality, hereditary anemias may cause mild, moderate, or severe anemia. In fact, some may be too severe to be compatible with life and may result in death of the fetus (unborn infant). On the other hand, some of these anemias are so mild that they are not noticeable and are incidentally revealed during a routine blood work.

What are the symptoms of anemia?

Some patients with anemia have no symptoms. Others with anemia may feel:

• Tired
• Fatigue easily
• Appear pale
• Develop palpitations (feeling of heart racing)
• Become short of breath

Additional symptoms may include:

• Hair loss
• Malaise (general sense of feeling unwell)
• Worsening of heart problems

It is worth noting that if anemia is longstanding (chronic anemia), the body may adjust to low oxygen levels and the individual may not feel different unless the anemia becomes severe. On the other hand, if the anemia occurs rapidly (acute anemia), the patient may experience significant symptoms relatively quickly.

How is anemia treated?

Sometimes iron supplements will also be needed to correct iron deficiency. In severe anemia, blood transfusions may be necessary. Vitamin B12 injections will be necessary for patients suffering from pernicious anemia or other causes of B12 deficiency.The treatment of the anemia varies greatly. First, the underlying cause of the anemia should be identified and corrected. For example, anemia as a result of blood loss from a stomach ulcer should begin with medications to heal the ulcer. Likewise, surgery is often necessary to remove a colon cancer that is causing chronic blood loss and anemia.

In certain patients with bone marrow disease (or bone marrow damage from chemotherapy) or patients with kidney failure, epoetin alfa (Procrit, Epogen) may be used to stimulate bone marrow red blood cell production.

If a medication is thought to be the culprit, then it should be discontinued under the direction of the prescribing doctor.

Reference.