Rh factor incompatibility occurs when a woman with Rh-negative blood comes into contact with Rh-positive red blood cells - most often from her baby during pregnancy or delivery. In these circumstances, the mother's immune system may recognize those red blood cells as 'foreign' and produce antibodies against them.
In subsequent pregnancies, these antibodies can cross the placenta and affect the baby's red blood cells, leading to what is known as perinatal hemolytic disease. This is why Rh factor incompatibility is a key topic in prenatal care and in assessing the risk of certain pregnancy-related complications.
-Human Anti D Immunoglobulin
