The Rh Factor

Have you ever heard of the Rh Factor? I had learned about it in various classes, but it wasn't until I was pregnant that I really learned what it was. Before I was pregnant I had no idea what my blood type was and now I never will forget. With every pregnancy I have I will have to receive a series of two Rh immune-globulin shots. So what exactly does that mean for you? Well, here is some information every expecting mother should be aware of: 

People with different blood types have proteins specific to that blood type on the surfaces 

of their red blood cells (RBCs). There are four blood types — A, B, AB, and O.

Each of the four blood types is additionally classified according to the presence of another protein on the surface of RBCs that indicates the Rh factor. If you carry this protein, you are Rh positive. If you don't carry the protein, you are Rh negative.

Most people — about 85% — are Rh positive. But if a woman who is Rh negative and a man who is Rh positive conceive a baby, there is the potential for a baby to have a health problem. The baby growing inside the Rh-negative mother may have Rh-positive blood, inherited from the father. Approximately half of the children born to an Rh-negative mother and Rh-positive father will be Rh positive.

Rh incompatibility usually isn't a problem if it's the mother's first pregnancy because, unless there's some sort of abnormality, the fetus's blood does not normally enter the mother's circulatory system during the course of the pregnancy.

However, during delivery, the mother's and baby's blood can intermingle. If this happens, the mother's body recognizes the Rh protein as a foreign substance and can begin producing antibodies (protein molecules in the immune system that recognize, and later work to destroy, foreign substances) against the Rh proteins introduced into her blood.

Other ways Rh-negative pregnant women can be exposed to the Rh protein that might cause antibody production include blood transfusions with Rh-positive blood, miscarriage, and ectopic pregnancy.

Rh antibodies are harmless until the mother's second or later pregnancies. If she is ever carrying another Rh-positive child, her Rh antibodies will recognize the Rh proteins on the surface of the baby's blood cells as foreign, and pass into the baby's bloodstream and attack those cells. This can lead to swelling and rupture of the baby's RBCs. A baby's blood count can get dangerously low when this condition, known as hemolytic or Rh disease of the newborn, occurs. 
For more information about Rh Incompatibility click here. For more information about the Rh immune-globulin shot click here.  Top Photo and bottom Photo.