The Four Stages Of Endometriosis Explained
The stage of endometriosis can be determined during surgery, not based on how much pain you feel or how much it affects your daily life. The staging system is what the surgeon sees inside the pelvis, and it doesn’t tell you much about what’s really going on in your own body. Understanding what the stages mean and what they do not mean can help you make better decisions about your care plan and stop comparing yourself to a number that does not begin to capture what you are going through.
Have you been given a staging diagnosis and want to know what this means for you in terms of health and what’s next? Floralia Wellness is here to work with you and your medical team to create a plan that encompasses everything.
How endometriosis is staged
To make a definitive diagnosis of endometriosis, a procedure called laparoscopy is used, where a surgeon uses a small camera inserted through a small cut near the navel to visually inspect endometrial growths, adhesions, and any changes to pelvic structures. While imaging techniques such as ultrasound or MRI can detect cysts on the ovaries and widespread adhesions, these methods do not always detect superficial growths, which is why laparoscopy is considered the gold standard.
What is found is then scored, which tells you what stage your endometriosis is, ranging from I to IV.
ASRM Point System and What the Scores Mean
The American Society for Reproductive Medicine uses a point system to grade the four stages of endometriosis. During laparoscopy, the surgeon examines endometrial growths, adhesions, involvement of ovaries, fallopian tubes, and other structures, giving them a score according to their depth, depending on their location.
A score ranging from 1 to 15 is for minimal or mild disease, or stages I and II. A score above 15 is for moderate disease, and the higher the score, the more severe the endometriosis. This system is good for comparison and for assessing the complexity of a procedure. What this system does not do is help in predicting symptoms or fertility. A comparison of the major classification systems showed that there is no ideal system available for endometriosis classification. The perfect system should be able to describe the extent of the disease and also be able to describe pain and fertility outcomes.
Why some specialists prefer classification by location instead
Some specialists in the treatment of endometriosis have adopted a classification of the condition based on location instead of points. This classification groups the condition into different categories. These include peritoneal endometriosis, which affects the lining of the pelvic cavity, and ovarian endometriomas, which develop as cysts in one or both ovaries. The third category is deep infiltrating endometriosis, in which the tissue penetrates more than 5mm into the pelvic organs.
This may be more useful for clinicians, as it gives an idea of where the disease is active. For example, a woman with deep infiltrating endometriosis involving the bowel will have different treatment needs from someone with superficial lesions on the peritoneum, even if their scores are similar. In reality, many clinicians use both scoring systems.
Comparative studies conducted on the use of the AAGL anatomy-based system and the traditional system of ASRM staging have shown that the anatomy-based system is more effective in distinguishing levels of surgical complexity. This is part of the reason why the field is shifting in this direction.
Stage I and stage II: minimal and mild endometriosis
Stage I minimal endometriosis is characterised by small isolated patches of endometrial tissue in the pelvic cavity, possibly on the peritoneum or the surface of the reproductive organs. Few or no adhesions are present. Stage II mild endometriosis is characterised by a larger number of endometrial implants that may be slightly deeper in the pelvic tissues. There may be mild adhesions involving several pelvic organs.
What superficial implants and deeper lesions may look like in each stage
In stage I, superficial implants may be seen as small red or dark spots, sometimes clear spots, resting on the surface of the peritoneum. At stage II, some implants may be seen to have invaded deeper into the tissue, and the surgeon may notice a mixture of superficial and slightly deeper lesions. Thin but not dense adhesions may begin to form between tissues.
The appearance may vary considerably. However, colour is not a good guide to the activity of the lesion. Some apparently inactive implants may be causing a lot of tissue response.
Why minimal staging does not mean minimal pain
A woman with stage I endometriosis may be in a tremendous amount of pain and be unable to work due to pelvic and menstrual pain. She may also be in pain during intercourse. On the other hand, a woman with stage IV endometriosis may have relatively minor symptoms and may only learn about the true extent of her endometriosis when she seeks fertility testing.
The difference exists because the staging system measures visible disease, not invisible inflammatory signalling and nerve involvement that can trigger endometriosis pain. Small lesions in nerve-rich areas can cause more severe pain than large cysts in non-sensitive areas.
A study of 244 patients verified that the stages of endometriosis were not necessarily correlated with pain, while the presence and location of the lesions were more important in the severity of pain, such as with deep dyspareunia. When you are told that your endometriosis is "only" in stages I or II, this does not mean that you are not feeling what you are feeling. If your painful periods are impacting your quality of life, seeking help from a painful periods specialist can help you find relief from your symptoms, regardless of your stage of endometriosis diagnosis.
Stage III: moderate endometriosis
In this stage, the disease process is advancing. The surgeon may find deep implants in several pelvic structures. There may be adhesions or scar tissue that bind the organs together. Small cysts may be present on one or both ovaries. The symptoms experienced by women in this stage include increased pain during menstruation and bowel movements. This is accompanied by increasing fatigue.
Deep implants, small ovarian cysts and filmy adhesions
Deep implants are seen in this stage as they grow into the tissue instead of just being on the surface as in stage III. These implants may be present on the uterosacral ligaments, the cul-de-sac, the outside of the bowel wall, or the surface of the ovary. Small ovarian cysts containing old blood and named chocolate cysts due to their colour may also be present. Filmy adhesions connect structures that are close to each other. Although filmy adhesions are not as strong as those in fibrous adhesions in stage IV, they can cause pain and decrease movement.
How distorted pelvic anatomy starts affecting fertility
At stage III, the distortion in the anatomy of the pelvic area starts affecting conception. Adhesions around the fallopian tubes may impede the ability of the fallopian tubes to detect the presence of an egg after the release of the egg during ovulation. Ovarian cysts may impact the quality and quantity of the egg. The chronic inflammation caused by the presence of endometriosis may impact the environment for the sperm.
Not all women at this stage will experience fertility challenges. However, it is at this time that the abnormal anatomy of the pelvis is a factor. It is at this time that the discussion of whether surgery to remove the endometrial tissue will increase the chances of conception through natural means or even IVF begins. A fertility naturopath can look at your symptoms holistically and work alongside your medical team to increase your chances of conception, even if there is a diagnosis of endometriosis and fertility challenges.
Stage IV: severe endometriosis
The most extensive form of the disease is Stage IV. It is characterised by the presence of several deep endometrial implants and large ovarian cysts. These cysts are often bilateral. Adhesions are also common and may link several pelvic organs together. These organs include the uterus, ovaries, fallopian tubes, bowel, and bladder.
Large cysts, dense adhesions and organ involvement
Endometriomas in the ovaries, which are large in size in stage IV, are several centimetres in diameter, causing a reduction in the functional size of the ovaries. Dense adhesions are thick fibrous bands that bind the organs to one another and the pelvic wall, distorting the pelvic anatomy. The organs involved are the rectum, sigmoid colon, bladder, and the ureters. When the bowel wall is involved with endometriosis, patients complain of severe bloating and constipation/diarrhea, especially during the menstrual cycle.
Deep infiltrating endometriosis beyond the pelvis
Deep infiltrating endometriosis is characterised by endometrial growths that have penetrated more than 5 mm into the tissue. While most endometriosis is found within the pelvic region, there have been reported instances where endometriosis, or specifically DIE, has penetrated beyond the pelvic region. While the diaphragm and abdominal wall have been reported, there have also been reported instances of endometriosis invading the lungs. When this happens, staging is not considered adequate to treat such a condition, and experts other than those in gynaecology have to be called upon.
Why your stage does not predict your symptoms
The staging system provides a common language for surgeons to explain what they see during a laparoscopy. The system is not intended to measure pain, fatigue, your menstrual cycle, or the effect of endometriosis on your mental health.
Pain in endometriosis is related to factors not included in staging. For example, endometrial implants that grow around or into nerve endings can cause pain that is disproportionate to their size. Inflammatory chemicals released by even small amounts of endometriosis tissue can, over time, sensitise the nervous system. When this happens, pain becomes part of the problem.
This fact is supported by a large international survey of nearly 3,000 participants from 59 countries. The survey found that symptom severity did not correlate with diagnosed stage and that all stages of the disease had significant diagnostic delays and symptom burdens. This is why some women with minimal amounts of endometriosis may experience severe pain, while others with large amounts of the disease may experience mild discomfort.
And then there is the overall symptomatology that is ignored in staging. Chronic fatigue, gastrointestinal symptoms, mood swings, and the mental health impact of living with a chronic disease are common across stages. In clinic, women in stages I or II often report feeling dismissed because their disease "doesn't look that bad." This leads to inadequate pain relief and makes women feel as though they are not taking their disease or their symptoms seriously enough. Your stage is a surgical descriptor. It is not a measure of your suffering.
The impact of staging on fertility and what the Endometriosis Fertility Index is
Endometriosis among women who are experiencing difficulties with conception ranges from 30 to 50%. It is one of the top causes of female infertility. There is a connection between staging and fertility; however, this connection is not absolute. Mild and moderate cases may result in temporary subfertility, but stage IV with adhesions and involvement of the ovaries bilaterally may impact the chances of conception. However, it is important to note that the stage does not guarantee pregnancy.
After your surgery for endometriosis, your specialist may determine your endometriosis fertility index, which considers your age, the duration of your infertility, your pregnancy history, the status of your fallopian tube and ovary, as well as the fimbria after your surgery, to give you a score that reflects the expected pregnancy rates in the following one to three years. The original development and validation of the EFI were based on prospective data from 801 patients. The first staging system for endometriosis that could predict pregnancy rates among women who attempted non-IVF conception after surgery.
What makes EFI better than staging is that it also takes into account functional outcomes rather than just the extent of disease. A woman with a moderate degree of endometriosis but good tubal and ovarian function after surgery may have a higher EFI and thus a better fertility prognosis compared to someone with a lower staging but poor tubal function. A score of 71 or above is only seen in cases with severe adhesions, in vitro fertilisation being the recommended option in such cases.
If fertility is a concern, ask your surgeon if they have calculated your EFI score. This will provide you with a more “practical” starting point than just a stage number. Knowledge about your hormonal profile from hormone testing will provide you with additional information about what may be affecting your fertility in conjunction with your staging diagnosis.
What to do after receiving a staging diagnosis
A staging diagnosis provides information on the current stage of your disease. What happens after this will depend on your symptoms, your fertility wishes, your past response to treatment, and the impact of your endometriosis on your quality of life.
Building a care team for endometriosis support
Endometriosis is a chronic condition that requires continuous management rather than a one-off procedure and a wait. Your care team may include a gynaecologist/endometriosis specialist for surgery, a pain expert if pain is a major factor, a pelvic floor physiotherapist if pain with intercourse or bowel motions is an issue, and a psychologist if the emotional toll of the condition is impacting your well-being.
Chronic inflammation and pain pathways, and hormonal imbalance, have a significant impact on the gut, nervous system, mood, and energy levels. It is not just about treating the lesions. A naturopathic approach takes a whole-person view of the condition and considers the underlying causes of how inflammation, hormonal balance, gut health, and stress pathways are connected. From this, a personalised protocol is devised in a way that is supportive of conventional treatment pathways, such as hormonal therapy or further surgical procedures. Endometriosis often presents with gastrointestinal symptoms such as bloating, constipation or diarrhea. Working with a healthcare practitioner who understands gut health is a significant factor in your overall well-being.
How naturopathic support fits into an endometriosis treatment plan
Naturopathic support fits into an endometriosis treatment plan alongside surgery and hormone therapies, as advised by your endometriosis specialist team. It is an approach that targets areas where conventional medicine may not always have the time to look, such as managing systemic inflammation, gut function (which has a direct impact on oestrogen metabolism), energy, and side effects of hormone therapies.
At Floralia Wellness, naturopathic support for patients with endometriosis starts with a detailed case review of your medical history, including any test results or surgical findings, current medication regimen, diet, stress levels, and symptoms. From this, the practitioner can better understand the whole picture and can devise a treatment plan that may include the use of specific herbal medicines that lower inflammation in the body, practitioner-strength nutritional supplements to correct any nutritional deficiencies, dietary changes that may impact hormones and promote bowel regularity, and lifestyle and stress management techniques to reduce the impact of cortisol.
A review published by the BMJ in 2022 defined endometriosis as a chronic inflammatory condition with an unpredictable clinical presentation. The importance of developing treatment approaches beyond the staging system was highlighted.
While no modality provides a lasting cure for endometriosis, what naturopathic support can do is help alleviate the symptoms you are experiencing, as well as address any underlying drivers of the condition and support you in between medical interventions. In addition, naturopathy can support and improve your long-term health and vitality. You can learn more about how our women's health team at Floralia can help you through our endometriosis natural medicine support page.
