Which blood type is prone to hemolysis?
Dec 12, 2025
Source: Cainiu Health
Dr. Zhang Lu
Introduction
In blood transfusion scenarios, type O red blood cells lack A and B antigens, but the plasma contains anti-A and anti-B antibodies. If a type O patient receives type A, B, or AB blood, the antibodies in the plasma may bind to the antigens on the transfused red blood cells, triggering a hemolytic reaction. Conversely, when type O blood is given by a donor to a non-type O recipient, the antibodies in the donor's plasma may also attack the recipient's red blood cells.
Generally, individuals with type O blood are more prone to hemolysis during blood transfusions or pregnancy, although other blood types may also experience hemolysis under specific mismatched conditions. If in doubt, it is recommended to consult a healthcare provider in advance. Detailed explanations are as follows:
In blood transfusion scenarios, type O red blood cells lack A and B antigens, but the plasma contains anti-A and anti-B antibodies. If a type O patient receives blood from a donor with type A, B, or AB, the antibodies in the recipient's plasma can bind to the antigens on the donor's red blood cells, triggering a hemolytic reaction. Conversely, when type O blood is donated to a non-type O recipient, the antibodies in the donor's plasma may attack the recipient's red blood cells.
During pregnancy, if the mother has type O blood and the fetus has type A or B blood, the mother’s anti-A or anti-B antibodies may cross the placenta and enter the fetal circulation, binding to fetal red blood cells and causing hemolytic disease of the newborn (HDN). This condition is less common in first pregnancies but becomes more likely in subsequent pregnancies as maternal antibody levels increase, thereby raising the risk of hemolysis.
Individuals requiring blood transfusions or pregnant women should undergo blood typing and antibody screening in advance to confirm blood compatibility and prevent hemolysis due to blood type incompatibility. Any symptoms of discomfort should be promptly evaluated and treated by medical professionals.
