Your doctor will ask you questions and do a pelvic exam. But your doctor won't know for sure that it's endometriosis until a surgeon can examine your body internally.
The most common procedure is called laparoscopy. During this surgery a thin, lighted tube is inserted into the abdomen through a small incision.
Women are usually unconscious when it's done. Many doctors remove a small piece of tissue and test it to confirm the diagnosis of endometriosis.