Endometriosis cannot be diagnosed with certainty by symptoms and physical examination alone. The healthcare practitioner may consider other conditions such as infections or tumors. One condition that may have similar symptoms to endometriosis is interstitial cystitis, or chronic inflammation of the bladder. Direct visualization of the endometriosis implants, typically via laparoscopic surgery, provides the definitive diagnosis. In order to diagnose endometriosis, the following steps may be taken:
- A biopsy of the suspected tissue may be accomplished by laparoscopy. During laparoscopy a tiny camera is inserted through small incisions in the patient's abdomen. Instruments are used to remove a small piece of tissue that is examined in the laboratory. More invasive surgery, called laparotomy, requires a larger surgical incision and does not rely on the use of a surgical camera.
- During surgery, samples of the suspected areas are taken and evaluated by a pathologist. Microscopic examination of tissue samples taken during surgery may reveal endometrial cells in areas outside of the uterus.