Rh factor/ Rh +ve/ Rh –ve refers to the presence of RhD antigen. Rh blood group system consists of 49 defined blood Rh antigen, most important 5 Rh antigen are C, c, D, E, e. RhD antigen is immunogenic, it provokes immune response and could cause transfusion reaction in the receipent. RhD antigen is an inherited protein that may be present on surface of RBC. If RBCs contain RhD antigen, it is Rh +ve. If not, it is Rh –ve. Rh factor is used to classify the blood type. For example; blood group A Rh positive is A +ve blood group. Rh factor is used to determine the blood compatability during pregnancy, blood donation, blood transfusion. If an Rh –ve person is given with Rh +ve blood, they develop hemolytic transfusion reaction During pregnancy , when the mother is Rh -ve and the baby is Rh +ve, this condition is Rh incompatability. If the mother comes in contact with the baby’s RBC during delivery or bleeding or abdominal trauma during pregnancy, the mother’s immune system produce a protein called Rh antibody. The Rh antibody could be harmful in subsequent pregnancy. If the next baby is Rh +ve, then these Rh antibody could cross the placenta and destroy the RBC, could cause Haemolytic disease of new born (HDN) in which the Rh antigen destroy the baby’s RBC in a faster rate than the baby’s body could replace it. Rh immune globulin injection is given to prevent the Rh antibody production in the mother.

1. Role of Rh factor in pregnancy
Vasugi.M
vaisuvasu07@gmail.com

2. Rh factor
• Rh factor/ Rh +ve/ Rh –ve refers to the presence of RhD antigen.
• Rh blood group system consists of 49 defined blood Rh antigen,
most important 5 Rh antigen are C, c, D, E, e. RhD antigen is
immunogenic, it provokes immune response and could cause
transfusion reaction in the receipent.
• RhD antigen is an inherited protein that may be present on surface
of RBC.
• If RBCs contain RhD antigen, it is Rh +ve.
• If not, it is Rh –ve.
• Rh factor is used to classify the blood type. For example; blood
group A Rh positive is A +ve blood group.
• Rh factor is used to determine the blood compatability during
pregnancy, blood donation, blood transfusion.
• If an Rh –ve person is given with Rh +ve blood, they develop
hemolytic transfusion reaction

3. Role in pregnancy
• During pregnancy , when the mother is Rh -ve and the baby is Rh
+ve, this condition is Rh incompatability.
• If the mother comes in contact with the baby’s RBC during delivery
or bleeding or abdominal trauma during pregnancy, the mother’s
immune system produce a protein called Rh antibody. The Rh
antibody could be harmful in subsequent pregnancy.
MOTHER FATHER BABY
Rh +ve Rh +ve Rh +ve
Rh –ve Rh –ve Rh –ve
Rh +ve Rh –ve Rh +ve/ Rh -ve
Rh –ve Rh +ve Rh +ve/ Rh -ve

4. • If the next baby is Rh +ve, then these Rh antibody could cross the
placenta and destroy the RBC, could cause Haemolytic disease of
new born (HDN) in which the Rh antigen destroy the baby’s RBC in a
faster rate than the baby’s body could replace it.
• Rh immune globulin injection is given to prevent the Rh antibody
production in the mother.