There are four major blood types determined by the presence or absence of two antigens, namely A and B, which are found on the surface of red blood cells.
In addition, there is also a presence or absence or absence of another antigen or protein in the red blood cells called the Rh factor. This can either be positive (Rh+) or negative (Rh-), thus creating a total of 8 possible blood types namely, -A+, A-, B+, B-, AB+, AB-, O+, O-.
So, if you want to donate it’s important to know your blood group or blood type and its compatibility with other groups.
Blood Groups & Compatibilities:
A positive (A+):
People with an A+ blood type can either donate to those with the same blood group or to people who are AB+.
And in the case of pf blood transfusion, an A+ person can receive blood from people with A and O groups.
A Negative (A-):
A person with Blood Group A- can donate to people with four Blood types – A-, A+, AB+ & AB-.
But they can receive blood only from those who have either the A- or O- blood group.
B Positive (B+):
The population with B+ blood type can donate to those who either have B+ or AB+ blood group and can receive blood from people who have B or O type.
B Negative (B-):
The population with B- blood type can donate to four blood types – B-, B+, AB+ & AB-.
But they can receive blood only from those who have either the B- or O- blood group.
AB Positive (AB+):
People with this blood group can donate only to other AB+ recipients but can receive blood from all types of blood groups, thus making it the Universal blood recipient.
AB Negative (AB-):
While the AB- blood type can receive blood from all the negative blood types, it can donate only to AB+ and AB-.
People with O+ blood type can donate to all those who have positive blood types, but they can receive blood from O+ and O-.
O- blood type is said to be the Universal blood donor as they can donate blood to people from all 8 types but can receive only from those who have the O-blood group.
So, if you are planning to donate your blood, it is good to consult a physician about any health issues and make sure to inform him/her, in case you are taking any medicines.