While some infertility physicians have begun using a simple blood test to diagnose early and mild-to-moderate cases of endometriosis in patients, other local physicians say there’s not a large enough body of evidence to prove its reliability. “I think we should be very receptive to this idea. I just think research and a little more study before we begin to accept it as a marker and then initiate treatment because of it,” says Howard Topel, M.D., Director of gynecologic surgery at Rush North Shore Medical Center in Skokie, who talked with writer Stephanie Fosnight in an article that appeared in the Pioneer Press.