What does my “blood type” mean?
Once your donated blood goes back to TBC’s lab, one of the first tests perfomed on it is to determine your blood type. The main red cell groups are A, B, AB, and O. These are types of antigens on the surface of the red blood cells.
- Group A blood has only the A antigen
- Group B has the only the B antigen
- Group AB has both
- Group O has neither
There is also an anitgen called a Rhesus (Rh) factor. Your blood is either Rh-positive or Rh-negative.
Combining ABO groupings and Rh factors gives us 8 main blood types: O+, O-, A+, A-, B+, B-, AB+, and AB-.
How common is my blood type?
Below is a chart of blood type distributions in the US (data from AABB.org).
Why are blood types important in transfusions?
When receiving a blood transfusion, a patient can only receive blood that is compatible with his or her type. Whole blood is rarely transfused – usually the blood is separated into components (red cells, white cells, platelets and plasma) and a patient will receive transfusions of one or more types of components.
Red blood cell transfusions:
When transfusing red blood cells, type O- blood is considered the “universal donor” because a patient with any blood type can receive O- red blood cells. Type AB+ is considered the “universal recipient” because a patient with AB+ blood can receive any blood type.
Red Blood Cells |
| If your blood type is: |
You can give to: |
You can receive from: |
| O Positive |
O+, A+, B+, AB+ |
O+, O- |
| A Positive |
A+, AB+ |
A+, A-, O+, O- |
| B Positive |
B+, AB+ |
B+, B-, O+, O- |
| AB Positive |
AB+ Only |
All blood types |
| O Negative |
All blood types |
O- only |
| A Negative |
A-, A+, AB-, AB+ |
A-, O- |
| B Negative |
B-, B+, AB-, AB+ |
B-, O- |
| AB Negative |
AB-, AB+ |
AB-, A-, B-, O- |
Platelet and plasma transfusions:
Platelet and plasma transfusions follow a different set of rules than red cells. With plasma transfusions, AB- is the “universal donor” and O+ is the “universal recipient.”
Platelets & Plasma |
| If your blood type is: |
You can give to: |
You can receive from: |
| O Positive |
O+ Only |
Any type |
| A Positive |
A+, O+ |
A+, A-, AB+, AB- |
| B Positive |
B+, O+ |
B+, B-, AB+, AB- |
| AB Positive |
AB+, A+, B+, O+ |
AB+, AB- |
| O Negative |
O-, O+ |
O-, A-, B-, AB- |
| A Negative |
A-, A+, O-, O+ |
A-, AB- |
| B Negative |
B-, B+, O-, O+ |
B-, AB- |
| AB Negative |
Any type |
AB- Only |
