What is the AAGL endometriosis classification system?

The AAGL endometriosis classification system is a standardized way surgeons describe what they found at surgery—where endometriosis is located, how extensive it is, and how complex the disease appears. Its goal is to create a more consistent “shared language” than older staging alone, especially for cases where symptoms and imaging don’t tell the full story.

Unlike simple stage labels, AAGL-style classification is meant to better capture real-world surgical complexity, including deeper disease that can involve structures like the uterosacral ligaments, rectovaginal space, bowel, bladder, or ureters. This matters because location and depth (for example, deep infiltrating disease) can drive very different symptoms and may change imaging choices and surgical planning. If you’re reading an operative report or trying to make sense of what a surgeon told you, our team can help translate the classification into what it likely means for your body, your symptoms, and the treatment path you’re considering.