After pregnant mothers are pregnant, they have to check many kinds of blood in outpatient maternity checkups, among which blood type is essential. So, if you are preparing for pregnancy or already pregnant, do you know about the rare blood type – Panda blood? There are two types of blood types, ABO and RH, and while we all know the ABO blood type, let’s talk about the RH blood type. The RH blood grouping system consists of five antigens: C, c, D, E, and e, with no d antigen. Those without D antigen are called RH negative or D antigen negative. In our Han Chinese population, the vast majority are RH-positive, and a small number are RH-negative – panda blood. So where does the risk for RH-negative mothers come from? From our baby – the fetus in the womb. During pregnancy, the fetus transfuses blood to the mother via the placenta. After an RH-negative mother and baby carry an RH-positive fetus during the first trimester, the fetal red blood cells enter the mother’s circulation through physiologic fetal-maternal transfusion, and a primary immune response occurs, which develops slowly. The antibodies produced are weak, mostly IgM, do not pass through the placenta, and the pregnancy can usually be successfully completed. When pregnant again, the mother is sensitized by the RH-positive fetus again, and a secondary immune response occurs, producing antibodies at a fast rate and strong antibodies. IgG antibody with high titer can enter the fetal circulation through the placenta and bind to destroy fetal red blood cells. Cause fetal anemia, edema, heart failure, etc.. As well as anemia, hemolytic jaundice and kernel jaundice in newborns, etc. In severe cases, stillbirth or neonatal death occurs. So, it is important to know your blood type after pregnancy. And, during outpatient maternity checkups, follow the doctor’s instructions for the necessary tests.