Rh Factor Incompatibility

Once you find out you are pregnant, one of the very first tests your doctor will order is a blood test. This is to determine your blood type and Rh factor. This information is very important to know early on in the pregnancy since it affects the baby’s health.

Four Blood Types Plus One More Factor

There are four blood types, A, B, AB and O. Each person has certain proteins in their blood which distinguish the blood type. There is another protein that is included in the classification of blood types and if this protein is present in the blood, then you are Rh positive. If the protein (antigen) is missing, then the result is Rh negative. Most people-about 85 percent-are Rh positive.

Rh Postive + Rh Negative = Potential Problems

If a woman is Rh negative and the father of the baby is Rh positive, there’s a very good chance the baby will be Rh positive as well. There is a great potential for health problems for the baby in such a situation. If it is the mother’s first pregnancy, the incompatibility problem is not so great because, barring an abnormality, the baby’s blood does not enter the mother’s circulatory system during pregnancy.

However, during the birthing process, the baby’s blood can mix with the mother’s blood and this is where the problem begins. If the baby’s Rh positive blood enters the mother’s body, her body will recognize the Rh protein as a foreign, enemy substance and can being to produce antibodies against the Rh positive protein. Blood transfusions with Rh positive blood, miscarriage and ectopic pregnancies are other ways Rh negative pregnant women can be exposed to the Rh protein.

When The Rh Factor Affects Baby

In a second or third pregnancy, serious danger may await an unborn Rh positive baby in the womb of an Rh negative mother. Her Rh negative antibodies recognize the presence of Rh proteins on the surface of the baby’s blood cells as a foreign substance and they will cross into the baby’s bloodstream to attack the cells. This can lead to swelling and rupture of the baby’s red blood cells causing the blood count to drop to dangerous levels. This is known as Rh disease of the newborn.

Thankfully, Medicine Has Come A Long Way

In years gone by, this was often a fatal occurrence; however, today modern medicine has found ways to help prevent complications due to Rh factor incompatibility. Treatment is in the form of a series of two Rh immune-globulin shots which are administered during the first pregnancy. These shots act as a vaccine which prevents the mother’s body from making more Rh antibodies which could potentially threaten another pregnancy or cause serious complications with a newborn.

The dangers of Rh factor incompatibility can result in severe damage to the newborn including anemia, jaundice, brain damage, and heart failure. It is important to have a blood test as soon as possible to determine Rh factor. With early detection and treatment of Rh incompatibility a mother can put her attention on more pleasant things-like the pending arrival of her new baby.