Has your wife had a laparoscopy done? The only way to know FOR SURE if a women has endo is through a surgical procedure called a Laparoscopy. However, there are 'clues' or symptoms that are used to determine whether or not a women has endo. Why do doctors rely on these symptoms for a diagnosis? Because whether or not a women has endo, the treatment is usually the same- birth control (and OTC pain killers). In advance cases of endo, a doctor may be able to physically feel the scar tissue caused by endo during a pelvic examination. At this point, surgery may be needed to remove the scar tissue.
Either way, no death!!! Like HmarieM said, it is not a serious disease... But VERY painful