MICROANATOMY

Detailed explanation-1: -HDN happens most often when an Rh negative mother has a baby with an Rh positive father. If the baby’s Rh factor is positive, like his or her father’s, this can be an issue if the baby’s red blood cells cross to the Rh negative mother. This often happens at birth when the placenta breaks away.

Detailed explanation-2: -If the mother is Rh-negative, her immune system treats Rh-positive fetal cells as if they were a foreign substance. The mother’s body makes antibodies against the fetal blood cells. These antibodies may cross back through the placenta into the developing baby. They destroy the baby’s circulating red blood cells.

Detailed explanation-3: -After the sensitization of the mother due to the formation of anti-D IgG immunoglobulins, future pregnancies are at risk for the development of the hemolytic disease of the newborn (HDN) due to Rh incompatibility if the fetus is Rh-positive.

Detailed explanation-4: -Most commonly, hemolytic disease is triggered by the D antigen, although other Rh antigens, such as c, C, E, and e, can also cause problems. Pregnancies at risk of HND are those in which an Rh D-negative mother becomes pregnant with an RhD-positive child (the child having inherited the D antigen from the father).

Detailed explanation-5: -HDN occurs when the immune system of the mother sees a baby’s RBCs as foreign. Antibodies then develop against the baby’s RBCs. These antibodies attack the RBCs in the baby’s blood and cause them to break down too early. HDN may develop when a mother and her unborn baby have different blood types.