question: I have a blood clot in my upper arm that I got as the result of an intervenous hook up. It is in a surface vein. I am 64 years old and have no health issues at all. I need to have rotator cuff surgery. They put me on blood thinners for the clot. Now a blood Dr. said I cannot take my permpro because she said it will interfere with the blood thinner. Is this true? I have been taking prempro for 10 years. I have tried to quit taking it a couple of times, but I have break through bleeding when I do. Is this normal?