Mom has blood type B and dad has blood type O. Hemolysis will not occur if the effect of Rh blood group is not taken into account. Mom is blood type B, dad is blood type O. The newborn’s blood type may be B, or O. Hemolysis will not occur. There is another type of Rh blood group incompatibility hemolysis, that is, when the mother is Rh-negative blood, if the newborn is Rh-positive blood, and is not the 1st fetus, neonatal hemolysis may occur. Neonatal hemolysis manifests as anemia after birth, early onset jaundice, and progresses very rapidly, hepatosplenomegaly, fetal edema, and also hypoglycemia and bleeding tendency, Rh hemolytic disease is a more critical type of hemolytic disease. When there is a possibility of hemolytic disease in newborns, you should communicate with obstetricians and gynecologists and neonatologists in advance and try to take measures in advance.