Final answer:
Rh incompatibility happens when an Rh-negative woman becomes pregnant with an Rh-positive fetus, not the other way around. This condition can lead to hemolytic disease of the newborn in subsequent pregnancies as the mother's body may produce antibodies against the fetus's Rh-positive blood cells.
Step-by-step explanation:
The statement that Rh incompatibility occurs when an Rh-positive woman is carrying an Rh-negative fetus is false. Rh incompatibility occurs when an Rh-negative woman carries an Rh-positive fetus. During the first pregnancy, an Rh-negative mother can usually carry an Rh-positive fetus to term without issue. However, if sensitized during the first pregnancy, the mother's immune system may generate anti-Rh antibodies. If she becomes pregnant with another Rh-positive fetus, these antibodies can cross the placenta and cause hemolyytic disease of the newborn (HDN). This can result in serious health issues for the fetus, including anemia, agglutination, and possible fatality without treatment.