The client's anti-A and anti-B antibodies cross the placenta and cause the destruction of the fetal red blood cells.

The client's blood contains the Rh factor and the newborn's does not, and antibodies that destroy red blood cells are formed in the fetus.

The client's blood does not contain the Rh factor, so she produces anti-Rh antibodies that cross the placental barrier and cause hemolysis of red blood cells in newborns.

The client has a history of receiving a transfusion with Rh-negative blood.