What is Rh Incompatibility and Isoimmunization
- What It Is
- Risk Factors
- Living With
- User Questions
- Alternative Treatment
- Care Guide
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- When to Contact a Doctor
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Rh Incompatibility and Isoimmunization Definition
One of the first tests performed at the beginning of a pregnancy is blood-type. This basic test determines your blood type and Rh factor. People with different blood types have proteins specific to that blood type on the surface of their red blood cells.
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 red blood cells that indicates your 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 incompatibility. The baby growing inside the Rh-negative mother may have Rh-positive blood, inherited from the father. Statistically, at least 50% of the children born to an Rh-negative mother and an Rh-positive father will be Rh positive.