Types and Stages of Endometriosis Everyday Health MenuNewslettersSearch Endometriosis Types and Stages of Endometriosis Can these classification systems help in the care and treatment of this disease? By Beth LevineMedically Reviewed by Kacy Church, MDReviewed: February 7, 2020Medically ReviewedConfused about endo staging? Join the club.Richard Drury/Getty Images; iStockHere are some startling numbers: According to the American College of Obstetricians and Gynecologists, an estimated 1 in 10 American women of reproductive age suffer from endometriosis, a chronic disease in which endometrial-like tissue grows outside of the uterus on other organs. It can cause debilitating pain, scar tissue, and infertility. While it is usually found in women ages 25 to 35, it can be found in girls as young as 11, notes the Endometriosis Foundation of America. Endometriosis may be found in 24 to 50 percent of women with infertility and in over 20 percent of those who have chronic pelvic pain, per the American Society for Reproductive Medicine (ASRM). And here’s another number to consider: Past research has found that women can wait anywhere from 3 to 11 years to receive a proper diagnosis. Endometriosis is still not well understood, and experts are still learning how one case differs from another, and why that matters. To help with diagnosis and treatment of the disease, various organizations have developed different ways of categorizing it.Related: Celebrities Who Speak Out About Endometriosis Sponsored Advertising Content Pelvic Pain Is Not Normal What to KnowDon’t let anyone write off painful periods or pain during sex as normal. If you have endometriosis, it can be treated. Categorizing the Stage and Type of Endometriosis DiseaseThe gold standard of diagnosis is laparoscopic surgery, during which a surgeon samples lesions for biopsy or excises the lesions. Once the medical care team has that information (biopsy results, visual verification of spread, depth, and affected organs), they may use different classification systems to categorize the disease. Currently there are four different ways to classify the disease: 1 Staging by Location Depth and Cysts The ASRM sorts diagnoses into four stages, “depending on location, extent, and depth of endometriosis implants; presence and severity of adhesions; and presence and size of ovarian endometriomas.”Stage 1 (1 to 5 points) A few superficial implants, mild adhesionsStage 2 (6 to 15 points) Slightly deeper implants and more adhesionsStage 3 (16 to 40 points) Deep implants, small chocolate cysts (ovarian endometriomas), deeper and filmy lesions, scarringStage 4 (more than 40) Deep implants, large chocolate cysts, many dense adhesions, more scarring 2 Classifying Stages of Deep Infiltrating Endometriosis Only The Enzian classification system is used as a supplement to ASRM’s system to analyze deep infiltrating endometriosis (DIE), when the disease nodules are more than 5 millimeters deep within tissue or an organ. This system grades disease by diameter of the nodules and localization. “It does have a better correlation to pain, but the Enzian system is not as widely adopted because it is newer, and the diagrams are not as widely available. It’s hard for the surgeons to visualize and score the disease,” says Ted Lee, MD, clinical professor in the department of obstetrics, gynecology, and reproductive sciences at the University of Pittsburgh, and vice president of the American Association of Gynecological Laparoscopists (AAGL). 3 Categorizing by Anatomical Location The Endometriosis Foundation of America (EndoFound.org) uses a more descriptive method that sorts the disease by its location in the pelvic and abdominal cavities, defined by the necessity and complexity of the involved organs.Category 1: Peritoneal Endometriosis A mild form that affects the peritoneum, the lining of the abdomen.Category 2: Chocolate Cysts Endometriosis cysts are in the ovaries, and risk breaking and spreading the disease further.Deep Infiltrating Endometriosis 1 (DIE I) Endometriosis has invaded the ovaries, rectum, and uterus.Deep Infiltrating Endometriosis 2 (DIE II) The most severe form, it affects organs within and without the pelvic cavity, including the bowels, appendix, diaphragm, heart, lungs, and (rarely) the brain. 4 Grading Fertility Levels The endometriosis fertility index (EFI) is a numbered scoring system that estimates a woman’s chances for pregnancy after laparoscopic surgery to remove endometriosis lesions. Created in 2010 by G. David Adamson, MD, EFI can also help identify patients who are the best candidates for in vitro fertilization (IVF). The factors taken into consideration are:ASRM endometriosis stageAgeDuration of infertilityPrevious pregnanciesFunctioning of organs such as fallopian tubes, ovaries, and fimbria (fingerlike projections from the ends of the fallopian tubes) Related: Speaking Endometriosis: Glossary of Terms Used for Endometriosis Symptoms, Tests, Treatments, and More What s Missing The Classification Systems Don t Illuminate Levels of Pain The jury is still out on whether these systems actually work. The big issue is that none of them predict symptoms very well. “If the tube has to transport egg, and sperm is blocked by scarring, that’s not captured in the ASRM staging. Also, the relationship between stage and pain is really unclear and unreliable, and none of these systems predicts whether someone has pain very well,” says Steven L. Young MD, PhD, professor at the University of North Carolina School of Medicine in Chapel Hill and chair of the ASRM endometriosis special interest group. Painful Symptoms or Lack of Symptoms Do Not Indicate Disease Severity A woman can have severe pain even though she has a mild stage of endometriosis; and vice versa, she can have little to no pain even though the disease is quite advanced. Dr. Young added that sometimes the only way a woman finds out she has it is when she is dealing with infertility. Also, some women will still have pain despite lesion removal; some will still get pregnant without removal. Obviously, more research is needed, since these categories often leave clinicians with more questions than answers. “We don’t even know if Stage 1 or 2 will often lead to 3 or 4. People who have the severe type probably have a biologically different disease than those with less severe, but we just don’t know,” Young says. Related: What Is Silent Endometriosis? Staging That Doesn t Correlate With Symptoms Is Confusing Women may have minimal or mild endometriosis but experience debilitating pain because of the inflammatory nature and location of the lesion (for example, it is close to nerves, or invaded an organ). “Staging could be a detriment then because they may feel they are being dismissed or unheard if we say it’s a mild case,” says Young. What About a Woman s Pain Level Nicole Noyes, MD, system chief of reproductive endocrinology and infertility at Northwell Health in New York City, concurred that the staging is not a magic bullet. “Over the years, I have not found it to correlate with the level of patient symptoms and thus don’t feel it necessarily predicts whether surgery will improve the situation. This is unlike cervical disease, where staging dictates best next treatments, so much so that there is now a physician app for Pap smear management.” Related: Tippi Endometriosis: Where Women With Endometriosis, Professionals, and Caregivers Get and Give Advice Each Case Is Unique Especially When Pain Quality of Life Family Planning Is Factored In Dr. Noyes says her endometriosis treatment plans are driven by pain levels, the presence of ovarian cysts, and whether a woman desires to become pregnant. “Many gynecologic conditions center around quality-of-life issues, such as pain, sleep, or wanting a baby. Tolerance for these varies from woman to woman, so I often request that a patient gauge the impact symptoms are having on day-to-day life activities. It’s important to appreciate that endometriosis doesn’t have a predictable course and, notably, doesn’t always worsen over time. This makes the decision to operate a measure of risk versus benefit. While surgery often provides the greatest chance for improvement, it also poses the most risk. Together, the patient and I decide what is best for her individual case.” The Endometriosis Fertility Index EFI Shows Promise In the case of EFI, while there are differing opinions, Aaron Budden, bachelor of medicine and master of medicine, of the Royal Hospital for Women in Sydney, announced his study findings at the 2017 meeting of the World Congress on Endometriosis by stating, “We’re quite confident that this is a very good system to give women a reasonable idea of their chances of conceiving naturally versus a recommendation to have IVF.” Young, however, points out, “I agree with this, but age and tubal status, included in the system, can predict fertility independent of endometriosis — so this is a hybrid between an endometriosis and a fertility risk factor classification system.” Classifications Benefit Doctors Researchers “Stages helps in research because you can classify something. It becomes a shorthand for clinicians to communicate with each other. They know what to expect and the likelihood of certain therapies. But while staging helps, I’d rather have a detailed description,” says Young. What the World Endometriosis Society Said About Disease Staging In 2016, the World Endometriosis Society grappled with the efficacy of the staging system, and concluded in an article published February 2017 in Human Reproduction: “This paper is the outcome of the first attempt to bring a global collaborative consensus to the classification of endometriosis, reflecting the best scientific evidence available and keeping uppermost the goal of improving quality of life for women with endometriosis. Our recommendation is that until better classification systems have been developed, surgeons should use a toolbox for surgical classification of endometriosis (that includes the r-ASRM system and, where appropriate, the Enzian and EFI staging systems) to maximize the information available to women following their surgery.” Translation: Clinicians should use the available systems as part of their arsenal for now until something better comes along, but employ other every other diagnostic tool as well. A combination of information provides the best chance at disease management. A Better Categorizing System Is Under Development According to Dr. Lee, the AAGL, European Society of Gynaecological Endoscopy, European Society of Human Reproduction and Embryology, World Endometriosis Society, and many other international organizations have started working on a unifying global system. “Hopefully we can develop something that everyone will agree on. However, it is in its infancy, and won’t be ready for a few years,” says Lee. NEWSLETTERS Sign up for our Women' s Health Newsletter SubscribeBy subscribing you agree to the Terms of Use and Privacy Policy. 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