Blood group RH

AsseyMethod: Agglutination
Abbrevation: B. G /Rh
Sector: Hematology
SampleType: WB(EDTA)S
S.Vol: -
Transport: at RT,at 2-8˚c
Storage: 12 hours at 20-25˚c , 2 weeks at 2-8˚c
Test Name: Blood group RH
Normal Range: -

This test is related to
Why get tested?

To determine ABO blood group and RhD type

When to get tested?

When you need to be transfused with blood or blood components or when you donate blood at a donation centre; pregnant women are tested to determine the risk of Rh incompatibility between the mother and foetus

Sample required?

A blood sample taken from a vein in your arm or from a heelprick in the case of an infant

Test preparation needed?


What is being tested?

Red blood cells (RBCs) have markers (proteins) or antigens on the surface of the cells. The blood group is determined by which proteins or antigens are present or absent on the red cell surface. Two major antigens or surface identifiers on human RBCs are the A and B antigens. People whose red blood cells have A antigens are considered to be blood group A; those with B antigens are group B; those with both A and B antigens are group AB; and those who do not have either of these markers are considered to have blood group O.

Another important blood group system is RhD. If the D antigen is present on the surface of RBC a person's blood type is RhD+ (positive); if it is absent, the person's blood is type RhD- (negative).

Our bodies naturally produce antibodies against the A and B antigens we do not have on our RBC. For example, a person who is blood group A will have antibodies directed against the B antigens on RBC and someone who is group B will have anti-A antibodies. People with blood group O have both anti-A and anti-B antibodies whereas those with group AB blood do not produce these antibodies.

These antibodies are useful for determining a person's ABO group and are significant in defining the types of blood that they can safely receive. For example, if a person who is group A with antibodies directed against the B antigen were to be transfused with blood that is group B, the antibodies would target and destroy the transfused red blood cells, causing severe, potentially fatal complications. Thus it is critical to match a person's blood type with the blood that is to be transfused.

How is the sample collected for testing?

A sample of blood is taken from a vein in your arm or from the tip of your finger (fingerstick). In newborns, blood from the umbilical cord or a small amount of blood from a heelstick may be used for testing.

Is any test preparation needed to ensure the quality of the sample?

No special preparation is needed for this test.