One of the most critical clinical implications of the Rh factor is its role in hemolytic disease of the newborn (HDN). This condition occurs when an Rh-negative mother carries an Rh-positive fetus. During childbirth, fetal blood cells can enter the maternal circulation, prompting the mother to produce anti-D antibodies. In subsequent pregnancies, these antibodies can cross the placenta and destroy the red blood cells of an Rh-positive fetus, leading to severe anemia and other complications in the newborn.
