With the results of these two tests, your blood type can be determined accurately. Rh typing is similar to ABO typing. Here, your blood is mixed with serum containing anti-Rh antibodies and then observed for coagulation. If coagulation occurs, then you have Rh-positive blood. If coagulation does not occur, then you have Rh-negative blood.
Blood typing is especially important during pregnancy .
If the mother is found to have type O or Rh-negative blood, then the father should also be tested. If the father has type AB or Rh-positive blood, then the mother's blood needs to be checked for Rh antibodies. If your blood clots when it is mixed with anti-A serum, then you have type A blood. If your blood clots when mixed with anti-B serum, then you have type B blood. If your blood does not clot in the presence of either serum, then you have type O blood.