Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Factor XI deficiency ?
    ### Response:
    Factor XI deficiency is a bleeding disorder that interferes with the body's clotting process. As a result, people affected by this condition may have difficulty stopping the flow of blood following dental extractions, trauma or surgery. Women with factor XI deficiency may also experience heavy menstrual periods or heavy postpartum bleeding.
    