Hemolysis does not usually occur in children with AB and B blood types. If AB blood has an AB phenotype and B blood can have a Bb or BB phenotype, the child of the combination may have either AB or B blood. If the mother has AB blood, she will have neither anti-A nor anti-B antibodies, and if the mother has B blood, she will have no anti-B antibodies and will have anti-A antibodies. Therefore, hemolysis does not usually occur regardless of whether the child has AB or B blood. ABO hemolysis mainly occurs when the mother has blood type O and the fetus has blood type A or B. In general, ABO hemolysis does not usually lead to serious consequences as long as it is detected and treated in time.