Blood group compatibility is critical for safe transfusions. The ABO and Rh systems determine which blood groups can receive from which donors.
The universal donor
O-negative is the universal donor — its red cells can be given to anyone in emergencies because it lacks A, B, and Rh antigens. This makes O- blood especially valuable in trauma situations where the patient's blood type is unknown.
The universal recipient
AB-positive can receive from any blood group. AB+ patients have the A, B, and Rh antigens, so their immune system doesn't react to any combination of donor blood.
Compatibility rules
- A patient can only receive blood that doesn't contain antigens they lack
- Rh-negative people should ideally receive Rh-negative blood
- In life-threatening emergencies, O- can be transfused to anyone
Why your blood group matters
Knowing your blood group helps you donate where you're most needed, and helps medical teams act faster in emergencies. Register on MediMapster and let nearby patients find you when they need your specific blood group.