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. A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the tourniquet is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding .