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Why does an Rh-negative mother with an Rh-positive fetus face a risk of erythroblastosis fetalis?
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blood group
The major component of human blood is the red blood cell.
Erythroblastosis fetalis occurs due to an immune incompatibility between an Rh-negative mother and an Rh-positive fetus. The risk arises through the following process:12
- Sensitization: During the birth of an Rh-positive infant, fetal red blood cells carrying the Rh factor (an antigen) may enter the motherās bloodstream. Because the mother is Rh-negative, her immune system recognizes these cells as foreign and produces anti-Rh [antibodies].123
- Immune Reaction: In subsequent pregnancies with an Rh-positive fetus, these maternal antibodies can cross the placenta and enter the fetal circulation.143
- Hemolysis: The antibodies attack and destroy the fetal red blood cells, a process known as [hemolysis]. This destruction leads to anemia and other severe complications, such as jaundice or, in extreme cases, fetal death.125
This condition is largely preventable by administering Rh immunoglobulin to the mother after the birth of an Rh-positive child, which destroys fetal cells before her immune system can become sensitized.143