Endo Overview

Since there is so much misinformation on endometriosis, I’ve written out this basic overview. Remember, this is educational information only and not medical advice (and I am not a doctor nor an expert on endo). Always check with your qualified medical professional before making any changes to your treatment plan.

Below you will find:

More endo-specific resources on my Resources page.

Resources for a multidisciplinary/full body approach to endo here.

Quick Facts

Endometriosis isn’t the uterine lining – it’s tissue that’s similar to it, but there are hundreds of differences between the two tissues.

Endometriosis does NOT slough and shed with your period and then that blood has no where to go. Endo does NOT act like the uterine lining (the endometrium) because it’s NOT the uterine lining.

Endometriosis isn’t caused by retrograde menstruation.

Hysterectomy, pregnancy, and medical (or natural) menopause don’t treat endometriosis. (In some instances, a hysterectomy can help people if their pain is actually because of problems originating in their uterus, such as adenomyosis. The role of a hysterectomy is on a case by case basis that would need to be discussed in depth with an experienced endo surgeon – not just any gynecologist.)

You can have endo and endo pain post-hysterectomy or post-menopause.

Endo can make its own estrogen via the aromatase enzyme.

Birth controls, hormones, and GnRh drugs (such as Lupron, Orilissa, Zoladex, Synarel, Visanne, Dienogest, Mirena IUD) don’t treat or diagnose endometriosis. These manage the SYMPTOMS ONLY (for some people – they don’t work in everyone, and any relief is typically temporary with pain returning once the person goes off the medication.) They don’t remove existing lesions, and endo can still progress while on them.

Endometriosis doesn’t just affect reproductive organs – it can be found in other body locations as well, such as the intestines, bladder, lung, or diaphragm.

Teens, premenarchal, and postmenopausal people assigned female at birth can have endometriosis. There is no age too old or too young. Endometriosis has been found in fetuses as well as people in their 70s!

You can have a negative ultrasound or MRI and STILL have endometriosis, as not all forms of endometriosis show up on scans. Additionally, when endometriosis signs are present on a scan, not all doctors have experience in recognizing them.

The only way to have a confirmed diagnosis of endometriosis is via surgery and a pathology report. Medication can’t diagnose endo (for example: having less pain on a medication such as Lupron doesn’t mean you have endo.) There is no blood test that diagnoses endo.

There are 2 types of surgery: ablation (superficial burning of endometriosis) and excision (cutting out at the root). With excision, the rate of recurrence (endo coming back) is around 7-20%. With ablation, disease persistence is fully expected, since the endometriosis wasn’t truly removed in the first place (and therefore persists).

Most gynecologists do ablation surgery. It takes special training and a high level of skill to do excision, so there are only about 200 excision specialists worldwide. See the treatment section below for more information and links for finding a doctor.

You aren’t doomed. Even without excision, many people live with less or no symptoms by changing their diet and lifestyle, reducing stress, treating co-conditions, or doing Traditional Chinese Medicine (such as acupuncture or Chinese herbs). See Endo is a Full Body Disease for a multidisciplinary approach to endo.

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What is Endometriosis?

Endometriosis is tissue similar to the endometrium (the uterine lining) but is NOT the endometrium, despite what many misinformed websites and even doctors say! Getting the definition correct is crucial for disease understanding and treatment. The following 2 definitions are from the Endo Girls Blog website article called Defining Endometriosis:

  • “Endometriosis is a systemic, inflammatory disease characterized by the presence of endometrial-like tissue found in extrauterine sites.” (Kennedy S. et al., 2005; Klemmt et al., 2018; Saunders et al., 2021). 
  • “Given the abundance of differential invasive, adhesive and proliferative behaviors between the native endometrium and the lesions of endometriosis (Delbandi et al., 2013), it is not merely just ‘rogue’ endometrium. The ectopic lesions of the disease resemble, but are not identical, to their eutopic counterparts (Ahn et. al., 2016). Studies have demonstrated that the tissues are functionally dissimilar (Zanatta 2010; Freger et al., 2021).”

Here is a quick overview from the Center for Endometriosis article Endometriosis: Understanding a Complex Disease:

  • “Defined correctly as the presence of tissue somewhat similar to the endometrium – endometrial-like – found in extrauterine sites, the aberrant processes involved in endometriosis give rise to pain, inflammation, development of endometriomas (“chocolate cysts”), fibrosis, formation of adhesions (fibrous bands of dense tissue), organ dysfunction and more. Alterations in certain biological processes of the endocrine and immune systems have also been observed with the disease, and endometriosis is embodied by a complexity of multiple immunologic abnormalities, endocrine alterations and unusual expression of adhesion molecules.”

These endometriotic lesions shouldn’t be in the body. While endo is most commonly found on the reproductive system, it has been found in all 11 body systems. Patients with endometriosis may have it on the ovaries, peritoneum (lining of the abdomen cavity and organs), bowel, bladder, uterosacral ligaments, rectovaginal septum, lung, diaphragm, or other parts of the body.

There are generally three accepted forms of endometriosis: Superficial (lesions are less than 5mm below the peritoneal surface), Ovarian Endometrioma (a cyst caused by endo on the ovary; also known as chocolate cysts), and Deeply Infiltrating Endometriosis (when lesions are more than 5mm below the peritoneal surface). DIE is considered the most severe form of endometriosis.

Endometriosis has glands and stroma, but doesn’t generally have blood vessels. Endometriosis glands secrete an inflammatory substance, which can irritate the surrounding tissue and destabilize nearby capillaries, causing bleeding in the surrounding tissues. This bleeding and inflammation can cause an immune response, the formation of fibrosis and adhesions, and pain. Endometriosis lesions can make their own estrogen via the aromatase enzyme. Endometriosis is often associated with changes in the surrounding tissues, such as neovascularity (where completely new blood vessels form), angiogenesis (where new blood vessels form from existing blood vessels) and neurogenesis (nerve growth). Studies have also demonstrated that endometriosis can have progesterone resistance, meaning that that the cells don’t respond to progesterone like they normally would.

Endometriosis is often staged using the American Society for Reproductive Medicine Classification System (ASRM). This categorizes endometriosis into 4 stages: stage I is minimal endometriosis, stage IV is the most severe. However, this staging system was designed with fertility in mind. It doesn’t correlate to the level of pain a person has, so someone with Stage I could have more pain than someone with Stage IV. Any stage of endometriosis can cause excruciating pain. Also, the staging system doesn’t take into account endo in locations such as the bladder, bowels, vagina, cervix, and more locations. The ASRM system has been criticized for having too much focus on the ovaries and adhesions.

A new staging system was developed called the AAGL 2021 Endometriosis Classification, which was specifically designed to measure surgical complexity. Like the ASRM classification, the stage does not correlate to the patient’s pain, and the staging system doesn’t attempt to give fertility outcomes. However, there is hope that it will help in the future with surgical reimbursements and improve financial incentives to completely treat disease, especially in complex cases needing significant expert time and effort. The staging system is available as an app called AAGL Endo Classification which you can download to your phone. What I like about the app is that the surgeon goes through the different areas of (abdominal) endo, determining if you have no endo there or less/more than 3 cm. Anatomic locations include: peritoneal, L/R ovary, L/R fallopian tube, L/R uterer, bladder, cul-de-sac obliteration, vagina, retrocervical, rectovaginal septum, rectum/sigmoid colon, small bowel/cecum, appendix. Then after they can download a PDF for you to see the locations/depth of your endo. 

For more info

  • Endometriosis: A Complex Disease This is a comprehensive overview of endometriosis from the Center for Endometriosis Care (CEC). I highly recommend you explore their online library of resources on endometriosis! “Led by internationally renowned endometriosis expert Ken Sinervo, MD, MSc, FRCSC, ACGE, the CEC is a global leader in the care and treatment of the disease.”

  • What is Endometriosis? – Make sure to check out all the articles in this section on Nancy’s Nook called “What is Endometriosis?”

  • Defining Endometriosis – Endo definition, sources, and a downloadable template to correct misinformation when you see the incorrect definition.

  • Extra Pelvic Not Rare and Indian Center for Endometriosis talk Extra Pelvic Endometriosis – “Dr. Abhishek Mangeshikar of Indian Center for Endometriosis and Dr. Wendy Bingham, PT, DPT of Extra Pelvic Not Rare discuss non reproductive system disease in the person with endometriosis. Chocked full of easy to understand statistics and pictures of extra pelvic disease this is a must see for anyone with bowel endometriosis, diaphragmatic endometriosis or extra pelvic disease.”

  • AAGL 2021 Endometriosis Classification: An Anatomy-based Surgical Complexity Score – Info on the new 2021 staging system.

  • 100 Questions & Answers About Endometriosis – Book by Dr. David Redwine, renowned excision surgeon.

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Delay in Diagnosis

About 1 in 10 people assigned female at birth have endometriosis. That’s estimated to be more than 200 million people worldwide (of all races, nationalities, and gender identities). In spite of its prevalence, there is often a long delay in diagnosis. Various studies have shown that the average time to be diagnosed is between 4-11 years.

Delays in diagnosis can result for many reasons. The first hurdle many endometriosis patients encounter is just trying to get a doctor to take them seriously when they report their pain. It may be due to the sex and gender bias in medicine for people assigned female at birth, a racial bias, or from the doctor’s lack of knowledge on endometriosis, but many patients report having their pain dismissed over and over again; being told that it’s “all in their head”, stress, or anxiety; or being told that pain for people assigned female at birth is “normal.” 

Once that hurdle to be taken seriously is crossed, gynecologists may believe the patient and suspect endometriosis but, due to a lack of training in the disease, are unable to diagnose it. They may not recognize the suggestion of its presence on scans such as ultrasounds or MRIs, or know that not all forms of endometriosis show up on these scans, and therefore a negative scan doesn’t necessarily mean the patient doesn’t have endometriosis. Laparoscopy with a pathology report is the only way to have a definitive diagnosis of endometriosis, but many gynecologists who are not skilled in recognizing the various visual appearances or locations of endometriosis may miss obvious signs of the disease during an exploratory surgery. 

Another delay may result from receiving a misdiagnosis. Endometriosis symptoms can present as digestive complaints, urological symptoms, full body pain, joint pain, or other symptoms, depending on where the endo is located and other factors. This may prompt a patient to see a gastrointestinal doctor, urologist, rheumatologist, or another specialist who misdiagnoses them with a different condition when the underlying cause is actually endometriosis. With a misdiagnosis or even a co-condition, such as Painful Bladder Syndrome, Irritable Bowel Syndrome, or Fibromyalgia, endometriosis symptoms can be blamed on this other condition.

For More Info

Some Great Books

  • Doing Harm: The Truth About How Bad Medicine and Lazy Science Leave Women Dismissed, Misdiagnosed, and Sick by Maya Dusenbery
  • Pain and Prejudice: How the Medical System Ignores Women―And What We Can Do About It by Gabrielle Jackson
  • Unwell Women: Misdiagnosis and Myth in a Man-Made World by Elinor Cleghorn

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Treatment (with info on how to find a doctor)

The treatment a person receives for endometriosis typically depends on the doctor’s skills, experience, and knowledge, so when looking for an endometriosis specialist, it’s important to understand endo and know about the different treatments so you can make an informed decision on your care.

Hormonal therapy – such as GnRh drugs (Lupron, Orlissa, Zoladex, Synarel, Prostap, etc) that medically induce menopause, birth control (the pill, Visanne, Dienogest, Depo Provera, etc) or the Mirena IUD – only manages the symptoms of endometriosis (in some people – not everyone sees symptom relief on these medications). These do not remove the endo lesions, and endo can still progress while on these medications. However, due to misinformation, many gynecologists who are not experts in endometriosis use these various methods as ‘treatment’ for the disease itself. They often wrongly believe that endometriosis will be ‘cleaned up’, ‘dried up,’ or ‘removed’ using one of these treatments, but this is simply not true. Additionally, any symptom relief is usually temporary and typically returns when the person stops the medication. 

GnRh drugs can have serious, long-term side effects. Make sure to research in depth to understand the risks/benefits before deciding to use them. See the resources below.

No medication can diagnose endo. Some doctors say that if a patient (who is still undiagnosed with endo) has pain relief on Lupron, it confirms that they have endo, but this isn’t true. There are other reasons as well why a person’s pain could go down in a low menopausal state. As stated in the previous section on diagnosis, the only way to have a confirmed diagnosis of endo is through a laparoscopy with a pathology report.

Pregnancy is not a treatment for endometriosis. If a doctor recommends that you “just get pregnant”, it is definitely a red flag that your doctor is not knowledgeable about endometriosis.

A hysterectomy is not a definitive treatment for endometriosis. This myth comes from the outdated endo theory of origin of retrograde menstruation, and the incorrect idea that endometriosis is from menstrual blood flowing backwards out the tubes into the abdominal cavity (more on this below in the Causes of Endo section). Endometriosis is not a disease of the uterus, but due to this misconception, unnecessary hysterectomies are performed on countless patients. It’s important to know that if a surgeon preforms a hysterectomy but doesn’t excise the endometriosis, that would actually be considered an incomplete surgery. To treat endometriosis, the surgeon has to excise the endometriosis lesions themselves.

In some instances, a hysterectomy can help people if their pain is actually because of problems originating in their uterus, such as adenomyosis. (Adenomyosis is not endometriosis, but is when the uterus muscle wall is invaded by tissue from the uterine lining.)  The role of a hysterectomy in a patient’s treatment is on a case by case basis that would need to be discussed in depth with an experienced excision surgeon – not just any gynecologist.

Diet, lifestyle, herbs, supplements, yoga, turmeric, celery juice, etc don’t remove, reverse, dissolve or cure endometriosis lesions, in spite of the many claims on the internet. However, any combination of these may help some people with their symptoms (but it varies per person). It’s important to know that:

  • Endo can still progress even if we are pain free.
  • Pain going away doesn’t mean our endo went away. This distinction is crucial.

See Endo is a Full Body Disease for ideas on a multidisciplinary approach to reduce inflammation, symptoms, and pain.

Ablation surgery is the superficial burning away of endometriosis on the surface level. However, the gold standard treatment for endometriosis is excision surgery, because it actually removes the disease completely from tip to root. At many centers for expertise in endometriosis where excision is performed as the surgical approach, the rate of actual disease recurrence/persistence (disease coming back/disease remaining) is around 7-20%. Many people find that their pain is significantly reduced or their quality of life has improved after excision. With ablation surgery however, many people find their pain returns within just months after surgery. With ablation, disease persistence is fully expected, since the endometriosis wasn’t truly removed in the first place (and therefore persists).

Additionally, excision has several more benefits over ablation:

  • Excision allows for the removed tissue to be sent to pathology for confirmation that it’s endometriosis, while due to the burning with ablation (and not the cutting out of tissue like with excision), the tissue is often unable to be sent to pathology for confirmation.

  • Due to the heat generated with ablation surgery, it usually cannot treat endometriosis on delicate tissues such as the bladder or intestines. With excision, the excision surgeon will often work with a multidisciplinary team, such as a general/bowel/thoracic/etc surgeon, to excise endometriosis from all organs where endo is present.

  • The burning of ablation surgery can cause more damage by causing scar tissue and leaving behind thermal damage, which can cause a painful foreign body giant cell reaction. It also leaves behind disease buried under scar tissue.

Excision surgery is renowned in the field as being an extremely difficult gynecological surgery, requiring a high skill level to remove endometriosis from the delicate tissues, as well as separate organs that may have fused together due to adhesions. For example, the patient may have an obliterated cul-de-sac (the intestines fused to the uterus), ovaries stuck to the uterus, or the intestines fused to the pelvic sidewall. It takes careful skill to be able to tackle the complex surgical challenges that endo presents.

The majority of gynecologists do ablation surgery, not excision. In 2020, it was estimated that there are only about 200 excision specialists in the US, even though this disease affects an estimated 8 million Americans and 200 million people worldwide! There are many barriers to access excision, such as cost, location, insurance hurdles, long wait times, or lack of a referral due to inadequate education among doctors that excision is indeed the gold standard for care. Unfortunately, excision remains a privilege that the majority cannot access instead of being the standard of care that everyone can access, and this is unacceptable, disgraceful, and heartbreaking.

Because endometriosis is a complex inflammatory condition that can affect the full body, it’s recommended that the patient work with a multidisciplinary team with excision at the cornerstone to address the disease from a full-body approach. Additionally, endometriosis may be present with other common co-conditions like Interstitial Cystitis/Painful Bladder Syndrome, pelvic floor dysfunction, small intestinal bacterial overgrowth (SIBO), gut dysbiosis, hormone imbalance, or irritable bowel syndrome (IBS). While many people do have significant improvement in their quality of life after excision surgery, others may need to address co-conditions and secondary pain generators to see more relief.

While excision typically gives the best outcome for removing the disease, there is no shame for choosing to do ablation surgery or choosing to manage symptoms via hormonal medications. What I advocate for is patients being able to make an informed decision. The problem is that many people are not being fully informed by their doctors of the risks or the limitations of treatments. When we have all the information, we can better choose the treatment option that is right for us – one that is affordable, accessible, and makes the most sense to us after having evaluated the risks, benefits, and our personal situation.

For More Info

Endometrioma Information

How to Find an Endometriosis Excision Surgeon

Anyone can call themselves an “expert” in endometriosis, because there is no formal standard in gynecology to qualify to use that title. A doctor might call themselves an endometriosis expert, but is only doing ablation or is only prescribing hormone treatments, and doesn’t even do excision.

A good endometriosis doctor is a highly skilled, high volume physician who understands endometriosis and how to properly diagnose and treat it. Often they solely treat endometriosis and don’t practice obstetrics or general gynecology at all. Even among doctors that do excision surgery, their skill levels and experience vary. Many people are also choosing to go to leading endometriosis centers that perform excision surgery as a component of their multidisciplinary approach to endometriosis, such as the Center for Endometriosis Care in Atlanta.

iCareBetter and Nancy’s Nook (links below) are two great starting places to find an excision surgeon. Even if you find a surgeon using their lists, it’s still important to vet the surgeon, look at patient reviews/lawsuits, and ask questions to make sure they have the appropriate skill level to treat you. Also, just because you have surgery with one of the doctors on their lists doesn’t guarantee that you will be pain free afterward, that you won’t have complications, or that endometriosis won’t persist or recur (but surgery outcomes and complication rates are generally much better in the hands of an expert).

Likewise, having surgery with an excision surgeon that you found and vetted that aren’t on these lists doesn’t mean you are guaranteed to have a bad outcome. Some excision surgeons do not have a social media platform, are not well-known, or work at academic institutions and rely on referrals instead of advertising to find patients. However, remember that anyone can call themselves an expert in endometriosis, so if you do find a surgeon that isn’t on one of these resources, it’s vital to vet the surgeon and ask questions to learn their success rates, complication rates, rates of reoperation/recurrence, ability to treat complicated cases, etc.

  • iCareBetter – This platform helps connect patients to endometriosis surgeons via a rigorous peer to peer double-blind vetting process for their surgical and excision skills. This platform is pretty new, so right now they don’t have many surgeons listed, but it’s growing as they vet more surgeons.

  • Nancy’s Nook Facebook Group – This private Facebook group has a list of excision specialists worldwide in the Files section, and in another file Nancy’s Nook explains how the surgeons are chosen/qualify to be put on their list. This is where I found my excision surgeon. You can use the search tool in their Facebook group to see reviews people have posted of these surgeons.

  • Open Payments – Look up your doctor and see if/what payments were made to them by drug and medical device companies.

  • How to Find a Doctor – A post from Nancy’s Nook, which has a great overview on what matters and what doesn’t matter when choosing a surgeon.

  • Questions to Ask Your Surgeon 1 – A list of questions from the Center for Endometriosis Care.

  • Questions to Ask Your Surgeon 2  – A list of questions to consider when vetting your excision surgeon, from Melissa at Eighty-Six the Endo.

  • Questions to Ask Your Surgeon 3 – Another great list of questions to consider when vetting your excision surgeon, from Kate at Endogirlsblog.

Dealing with Insurance

In many cases, excision surgery is considered out-of-network for US insurance providers. That being said, there are also excision surgeons who are in-network with insurance; it will depend on the individual surgeon.

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No one knows the cause of endometriosis, but evidence is stacked against the theory of retrograde menstruation. Also known as Sampson’s theory, this theory is that menstrual blood leaks out of the tubes into the pelvis and these bits of endometrium implant themselves in the pelvis where they land and grow into endometriosis. This 100-year-old theory has never been proven and has so many holes in it at this point that the likelihood of it being true seems almost impossible. Unfortunately, many ineffective treatment options are based on this unproven theory, at a detrimental cost to us patients.

While there are several theories to the cause of endometriosis – and there may indeed be multiple factors and causes playing into why a person has it – one theory of origin is Mulleriosis. This proposes that endometriosis is due to a developmental defect in the formation of the Mullerian duct system when we are embryos (with involvement of the HOX genes). The Mullerian duct is the very beginnings of the reproductive system that will later form the fallopian tubes, uterus, uterine cervix, and superior aspect of the vagina. Cells that are laid down during its formation may have abnormal migration (they may not go to the right spot) or abnormal differentiation (when a cell changes from one cell type to another) and later develop into endometriosis.

In fact, endometriosis has been found during autopsy in some fetuses assigned female at birth (who died for other reasons) at around the same rate, 10%, that it is found in the population of people assigned female at birth today. The theory of embryonic origin explains:

  • how endo can be found anywhere in the body.
  • how endo has been reported in the medical literature in around 20 people assigned male at birth. This is because as fetuses, we have the beginnings of both the (what’s considered) “male” and “female” reproductive tracts during the first 6-8 weeks in the womb. Typically, one regresses and the other develops, so that the fetus has that specific set of reproductive organs. However, cells from the reproductive track that regressed can remain behind.
  • why endo is found in embryonic patterns in the body and has low recurrence after true excision.

“The definitive cause(s) of endometriosis remain under debate, though demonstrated association with a number of hereditary, environmental, epigenetic and even certain menstrual characteristics exist. Current research implicates HOX genes, mesenchymal stem cells and certain immunologic factors in disease origin; nonetheless, no single theory explains endometriosis all those affected; more likely, a composite of several mechanisms is involved.” [Quote from the Center for Endometriosis article: Endometriosis: a Complex Disease]

For More Info

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My Thoughts

The standard of care for endometriosis is disgraceful, especially for a disease that affects 200 million people worldwide. More people suffer from endometriosis than Alzheimer’s, Lupus, Multiple Sclerosis, Inflammatory Bowel Disease, Arthritis, and Parkinson’s Disease combined – yet most of the general population has never heard of endo. We need a cure. We need recognition. We need to go to the doctor and be taken seriously when we say we are terrified to get our periods because of the crushing pain that it brings. We need funding for endometriosis research, and research that isn’t focused on proving the outdated theory of retrograde menstruation. We need education in schools and even among doctors that period pain is not normal, painful sex is not normal, and painful bowel movements are not normal. It shouldn’t take 10+ years to be diagnosed with such a common disease, and once diagnosed, we should have access to excision to remove the disease from our bodies, instead of being offered subpar treatments based on misinformation. Some doctors even refuse to treat people with endometriosis who are not experiencing infertility or trying to get pregnant, completely disregarding that the other symptoms such as pain, fatigue, and digestive problems are severely diminishing our quality of life.

Not only do endometriosis patients grapple with chronic and often debilitating pain that ravages our lives, often affecting our relationships, our careers, and our mental well-being, but we face dismissal and lack of education from the very medical professionals who we are supposed to turn to for help. The psychological impact on us is double. We are weighed down by the debilitating symptoms and lack of treatment, and weighed down again by being told that it isn’t real and that we should see a psychologist for what these medical professionals perceive as “anxiety.”

Many of us with endo begin having symptoms from 9, 10, 12 years old. It’s heartbreaking to me that from such a young age, we go through so many trials and tribulations because we are fighting not only against endometriosis, but against a system of misinformation, dismissive doctors, lack of access to expert care, all while battling the pain, fatigue, nausea, doubt, and more.

The endometriosis community is an incredible group of people, and we will keep advocating so that future generations don’t have to suffer as we have.

For more info

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