Hemolytic disease of the fetus and newborn (HDFN) often results in severe anemia resulting in intrauterine transfusions and increased risk of fetal death. According to the recently published phase 2 UNITY study of 13 pregnancies, nipocalimab (a human monoclonal antibody that blocks the Fc receptor) given during pregnancy helps to prevent maternal IgG alloantibodies from crossing the placenta and delays…