Rh factors in Human Blood
The Rh factor is a type of protein that is present on the surface of red blood cells in most people. If a person has the Rh factor, they are Rh-positive (Rh+), and if they do not have the Rh factor, they are Rh-negative (Rh-).
Rh factors are important in blood transfusions and in pregnancy. If an Rh-negative woman becomes pregnant with an Rh-positive fetus, there is a risk that her immune system will recognize the Rh factor as foreign and produce antibodies against it. This is known as Rh sensitization and can cause hemolytic disease of the newborn (HDN), a condition in which the mother’s antibodies attack the baby’s red blood cells, leading to anemia and other complications.
To prevent Rh sensitization in a pregnancy, an Rh-negative mother may receive an injection of a medication called Rh immunoglobulin (RhIg) at certain points during the pregnancy and after delivery. RhIg works by binding to any Rh-positive fetal cells in the mother’s bloodstream before they can stimulate her immune system to produce antibodies.
In blood transfusions, it is important to match the Rh factor of the donor blood with the recipient’s blood to prevent a similar immune response. For example, an Rh-negative person should receive Rh-negative blood to avoid developing antibodies against the Rh factor.
Rh factors are just one aspect of blood grouping, which also includes the ABO blood group system and other less common blood group systems. Knowing a person’s blood type and Rh factor is important for medical procedures involving blood or blood products to ensure compatibility and prevent complications.
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