The common clinical blood types are divided into two systems, namely ABO blood group system and Rh blood group system. If hemolytic disease occurs in newborns, there are usually ABO hemolysis and Rh hemolysis, as follows: 1. ABO hemolysis mainly occurs when the mother is type O and the father is type A, B or AB blood; because there are more antibodies similar to ABO in nature, ABO hemolysis is about 40%-50%, and it occurs in the second child; 2. Rh hemolysis is not the same as ABO, the mother is Rh-negative and The father is Rh-positive and Rh-negative is called panda blood. In nature, because there are fewer such antigens, hemolysis occurs in Rh blood type incompatibility, less often in the first child, unless there is a history of large month miscarriage before the first child, or exposure to Rh antigen in blood transfusion, etc. Hemolysis in the second child can be prevented if the person with Rh blood group incompatibility is immunized with antibody immunoglobulin at week 28 and the antibody immunoglobulin injection is given intramuscularly within 72h after delivery, especially within 24h.