The Rh factor is a red blood cell surface antigen. 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 red blood cells. A baby's blood count can get dangerously low when this condition, known as hemolytic or Rh disease of the newborn, occurs.
Rh incompatibility rarely causes complications in a first pregnancy and does not affect the health of the mother. But Rh antibodies that develop during subsequent pregnancies can be potentially dangerous to mother and child. Rh disease can result in severe anemia, jaundice, brain damage, and heart failure in a newborn. In extreme cases, it can cause the death of the fetus because too many red blood cells have been depleted.
If you're not sure what your Rh factor is and think you're pregnant, it's important to start regular prenatal care as soon as possible - including blood-type testing. With early detection and treatment of Rh incompatibility, you can focus on more important things - like welcoming a new, healthy baby into your household.
You must consult your doctor for the treatment.
The information contained in this site is given to inform you and does not substitute for consulting a doctor or a pharmacist.