Endometriosis is a condition in which tissue similar to the endometrium grows outside the uterus, leading to pain, particularly during menstruation, and potential fertility issues. Research suggests that it may be more accurately defined as a syndrome that encompasses both the ectopic tissue and the symptoms experienced because some individuals may have the tissue without any symptoms.
What is endometriosis?
The endometrium is the type of tissue that lines the inside of the uterus. In endometriosis, tissue similar to the endometrium grows outside the uterus. Endometriosis can be a painful condition, especially during menstruation, and endometriosis can impair fertility. Research into the patient experience of this condition has suggested that we redefine endometriosis as a syndrome that includes both these ectopic uterine tissue deposits and the symptoms they cause, since some people with ectopic endometrial tissue don’t experience any symptoms.[1]
What are the main signs and symptoms of endometriosis?
The main symptoms are pain and infertility.[2][1] Some of the common symptoms that people with endometriosis may experience are: Painful periods (dysmenorrhea); pain during or after sex (dyspareunia); pain while urinating (dysuria) or defecating (dyschezia); unusually heavy periods or bleeding between periods; infertility; and fatigue, diarrhea, constipation, bloating or nausea, especially during menstrual periods. It’s possible for people with endometriosis to experience all, some, or none of these symptoms. Some people with endometriosis may experience atypical symptoms, like back pain, chest pain, leg pain, rectal bleeding, or acid reflux, and this could be related to inflammation or to the location of the lesions.[3]
How is endometriosis diagnosed?
Endometriosis has a wide symptom range, and needs to be diagnosed by a doctor; the gold standard for diagnosis is laparoscopy (minimally invasive surgery), although nonsurgical diagnostic tools are being investigated. In terms of imaging, MRI is showing the most positive results, although more studies are needed before it can replace surgical diagnosis. Transvaginal ultrasound may also be useful for endometriosis involving the rectum and sigmoid colon.[4] Blood markers could also be used for diagnosis in the future, although the appropriate marker hasn’t yet been found. Anti-endometrial autoantibodies, interleukin 6 (IL-6), and cancer antigen 125 (CA 125) have been considered, but are not accurate enough to replace the current diagnostic standard.[5]
What are some of the main medical treatments for endometriosis?
Endometriosis is a chronic condition requiring long-term treatment which focuses on symptom management. Symptoms can be managed medically through surgery to remove endometriotic tissues, and through long-term medication for hormonal management. Hormone treatment, in the form of tablets, skin patches or implants, may effectively reduce pain symptoms, but may not be appropriate in patients with infertility, or in women who are trying to become pregnant. Endometriosis-impaired fertility can be addressed by assisted reproduction techniques, such as in vitro fertilization (IVF).[6] Although surgery isn’t considered a cure (because endometriotic tissue may return after surgery), it can reduce painful symptoms in the short term, and hormonal treatment can delay the tissue’s regrowth.[7]
Have any supplements been studied for endometriosis?
Several vitamins and supplements have been studied, including vitamin D,[8] melatonin,[9] and vitamins E and C. Vitamin E, with or without vitamin C, seems to improve pain symptoms. Vitamin D also improves pain symptoms to a lesser extent. Both effects are small, but given their good safety profiles, these supplements are worth considering in conjunction with other medical interventions.[10] Melatonin has limited evidence to support its use, but it might improve pain symptoms, sleep quality, and mood symptoms in people with endometriosis.[11]
How could diet affect endometriosis?
Multiple studies have investigated the relationship between diet and endometriosis. There is weak evidence that a healthy diet, with reduced alcohol intake and increased physical activity, is associated with a lower risk of getting endometriosis.[12] A diet high in fruit, particularly citrus fruit, might lower the risk for endometriosis.[13]
Are there any other treatments for endometriosis?
Some people may find that some of their symptoms of endometriosis, such as painful menstruation, can be non-medically managed. Some people with endometriosis develop chronic pelvic pain, which may be manageable with pelvic physiotherapy and myofascial trigger point dry needling.[6]
What causes endometriosis?
The endometrium is the lining of the uterus. Endometriosis is caused by endometrium-like cells growing outside the uterus, usually accompanied by inflammation.[12] Researchers haven’t yet pinned down exactly why this happens.[14]
Research FeedRead all studies
Can a low-FODMAP diet improve gastrointestinal symptoms in endometriosis?
In this randomized crossover trial in women with endometriosis and gastrointestinal symptoms, 60% of participants had an improved overall gastrointestinal symptom score on a low-FODMAP diet, compared to 26% of participants on a control diet.
Can dietary supplements improve endometriosis-associated pain?
Can vitamin D reduce pain from menstrual cramps or endometriosis?
Fruit intake was not associated with endometriosis
Chamomile and flaxseed for women with endometriosis
Frequently asked questions
What is endometriosis?
The endometrium is the type of tissue that lines the inside of the uterus. In endometriosis, tissue similar to the endometrium grows outside the uterus. Endometriosis can be a painful condition, especially during menstruation, and endometriosis can impair fertility. Research into the patient experience of this condition has suggested that we redefine endometriosis as a syndrome that includes both these ectopic uterine tissue deposits and the symptoms they cause, since some people with ectopic endometrial tissue don’t experience any symptoms.[1]
So endometriosis is just uterine lining growing outside the uterus?
Quick answer:
Endometriosis involves growths that are not identical to the uterine lining and have distinct differences that are observable under a microscope. Although hypotheses like retrograde menstruation suggest a cause, many women with retrograde menstruation do not develop endometriosis, and some individuals who have never menstruated can still be diagnosed with the condition.
Sort of, but endometriotic growths aren’t quite the same as the endometrial lining in the uterus. They’re not actually true endometrial tissue; they usually have differences that are visible under the microscope. Theories about development include “retrograde menstruation,” in which menses flow back up through the fallopian tubes and into the pelvic cavity; however, most women experience retrograde menstruation, and don’t experience endometriosis, and some people who have never menstruated have been diagnosed with endometriosis.[15][16][17] Other theories involve transformation of other cells into endometriotic cells.[18]
Where can endometriosis occur?
Quick answer:
Endometriosis most commonly occurs in the pelvic cavity, particularly in the ovaries, fallopian tubes, and pelvic lining. Although rare, it can also be found in other organs such as the kidneys, eyes, liver, pancreas, intestines, and brain.
Endometriosis is most commonly found in the pelvic cavity, with some of the most common sites being the ovaries, fallopian tubes, and pelvic lining, but while it’s rarer outside the pelvic cavity, endometriosis can occur anywhere in the body. It’s extremely rare, but endometriosis can even occur in other organs like the kidneys, eyes, liver, pancreas, intestines, and brain.[19]
Is endometriosis an autoimmune disorder?
Quick answer:
Recent research indicates a potential association between endometriosis and certain autoimmune disorders, but it remains unclear whether one condition influences the other or whether they share common causes. Preliminary evidence suggests that immunotherapy may be a future treatment option for endometriosis, although further research is needed.
Recent research has noted an association between endometriosis and certain autoimmune disorders, such as systemic lupus, inflammatory bowel disease, rheumatoid arthritis, and celiac disease.[23] However, this association presents more questions than answers: It is difficult to establish which disease process started first, especially since endometriosis diagnoses are often delayed. Furthermore, we do not yet know whether the presence of endometriosis might lead to other autoimmune disorders (or vice versa), or whether these illnesses might share similar underlying causative pathophysiologies or genetic links.[24]
That said, there is some preliminary evidence that immunotherapy could be used to treat endometriosis in the future. The immune system and its components, including neutrophils, macrophages, T-cells, mast cells, and many more, seem to play a role in the development of endometriosis, which implies that some treatments usually used for autoimmune conditions, such as interferons or antitumor necrosis factor, could be used in endometriosis. While the current research is promising, a lot more work needs to be done before immunotherapy could become a regular part of the treatment for endometriosis.[16][24]
What are the main signs and symptoms of endometriosis?
The main signs and symptoms of endometriosis include pain, particularly during menstruation and intercourse, and infertility. Other common symptoms may involve heavy periods, fatigue, gastrointestinal issues, and atypical pains, and individuals experience varying combinations of these symptoms.
The main symptoms are pain and infertility.[2][1] Some of the common symptoms that people with endometriosis may experience are: Painful periods (dysmenorrhea); pain during or after sex (dyspareunia); pain while urinating (dysuria) or defecating (dyschezia); unusually heavy periods or bleeding between periods; infertility; and fatigue, diarrhea, constipation, bloating or nausea, especially during menstrual periods. It’s possible for people with endometriosis to experience all, some, or none of these symptoms. Some people with endometriosis may experience atypical symptoms, like back pain, chest pain, leg pain, rectal bleeding, or acid reflux, and this could be related to inflammation or to the location of the lesions.[3]
Are there different severities of endometriosis?
Quick answer:
Yes, endometriosis can vary in severity and is commonly classified using 3 grading systems: the American Society of Reproductive Medicine's stages I–IV, the Endometriosis Fertility Index (EFI), and the Enzian classification system. The American Society of Reproductive Medicine's system is the most widely used, whereas the Enzian system is better for describing deeply infiltrating endometriosis, and the EFI focuses on fertility effects.
Yes. There are three grading systems commonly in use. According to the American Society of Reproductive Medicine guidelines, an individual’s endometriosis can be classified as stages I–IV, as follows: Stage I is minimal, Stage II is mild, Stage III is moderate, Stage IV is severe.[20] Endometriosis can also be graded by the Endometriosis Fertility Index (EFI), which grades endometriosis according to its impact on fertility,[21] or the Enzian classification system, which is designed to describe both the location and severity of endometriosis.[22] The most commonly used system is the American Society of Reproductive Medicine’s, but deeply infiltrating endometriosis (DIE) is better described by the Enzian system, and the EFI is much more useful for predicting endometriosis’s impact on fertility.
How is endometriosis diagnosed?
Endometriosis is diagnosed primarily through laparoscopy, which is the gold standard for diagnosis, although MRI and transvaginal ultrasound are under exploration as nonsurgical options. Blood markers for diagnosis are also under investigation, but none have proven accurate enough to replace surgical methods at this time.
Endometriosis has a wide symptom range, and needs to be diagnosed by a doctor; the gold standard for diagnosis is laparoscopy (minimally invasive surgery), although nonsurgical diagnostic tools are being investigated. In terms of imaging, MRI is showing the most positive results, although more studies are needed before it can replace surgical diagnosis. Transvaginal ultrasound may also be useful for endometriosis involving the rectum and sigmoid colon.[4] Blood markers could also be used for diagnosis in the future, although the appropriate marker hasn’t yet been found. Anti-endometrial autoantibodies, interleukin 6 (IL-6), and cancer antigen 125 (CA 125) have been considered, but are not accurate enough to replace the current diagnostic standard.[5]
Is endometriosis a form of cancer?
Quick answer:
Endometriosis is not a form of cancer; it is a benign condition. Although it is associated with an increased risk of ovarian cancer, most people with endometriosis will not develop it and only rarely can they develop endometriosis-associated adenocarcinoma.
No. Endometriosis growths aren’t cancer, and endometriosis is a benign condition. It is associated with an increased risk of ovarian cancer, but the majority of people with endometriosis won’t develop ovarian cancer.[6] Rarely, people who have had endometriosis can later develop endometriosis-associated adenocarcinoma.
What are some risk factors for developing endometriosis?
Quick answer:
Risk factors for developing endometriosis include early menarche, short menstrual cycles, low BMI, having few or no children, imperforate hymen, and uterine abnormalities. Additionally, there is an observed association with alcohol intake and smoking, though it is not definitively causative.
Does the severity reflect the severity of the symptoms?
Quick answer:
The grading systems for endometriosis primarily indicate the extent of endometriotic growths, but there is not always a direct correlation between the severity of these growths and the symptoms experienced. Individuals with extensive growths may have mild symptoms, whereas those with less tissue may suffer from severe pain.
The three grading systems of endometriotic severity chiefly reflect the extent of the endometriotic growths. However, the severity of the symptoms experienced by a person with endometriosis isn’t always correlated with this. People with extensive growths may experience few symptoms, and people with relatively less endometriotic tissue may experience severe pain.
What are some of the main medical treatments for endometriosis?
Medical treatments for endometriosis focus on symptom management through surgery to remove endometriotic tissue and long-term hormonal medication, which can alleviate pain but may not be suitable for individuals who are trying to conceive. Although surgery can provide short-term relief, it is not a cure, and assisted reproduction techniques like IVF can address fertility issues related to the condition.
Endometriosis is a chronic condition requiring long-term treatment which focuses on symptom management. Symptoms can be managed medically through surgery to remove endometriotic tissues, and through long-term medication for hormonal management. Hormone treatment, in the form of tablets, skin patches or implants, may effectively reduce pain symptoms, but may not be appropriate in patients with infertility, or in women who are trying to become pregnant. Endometriosis-impaired fertility can be addressed by assisted reproduction techniques, such as in vitro fertilization (IVF).[6] Although surgery isn’t considered a cure (because endometriotic tissue may return after surgery), it can reduce painful symptoms in the short term, and hormonal treatment can delay the tissue’s regrowth.[7]
Have any supplements been studied for endometriosis?
Several vitamins and supplements — including vitamin D, melatonin, and vitamins E and C — have been studied for endometriosis, and vitamin E has shown some improvement in pain symptoms. Although vitamin D also helps with pain to a lesser extent, melatonin has limited evidence but may enhance pain, sleep quality, and mood.
Several vitamins and supplements have been studied, including vitamin D,[8] melatonin,[9] and vitamins E and C. Vitamin E, with or without vitamin C, seems to improve pain symptoms. Vitamin D also improves pain symptoms to a lesser extent. Both effects are small, but given their good safety profiles, these supplements are worth considering in conjunction with other medical interventions.[10] Melatonin has limited evidence to support its use, but it might improve pain symptoms, sleep quality, and mood symptoms in people with endometriosis.[11]
How could diet affect endometriosis?
Research suggests that a healthy diet — characterized by reduced alcohol intake and increased physical activity — may be associated with a lower risk of endometriosis. Additionally, a diet rich in fruits, especially citrus fruits, could further decrease this risk.
Multiple studies have investigated the relationship between diet and endometriosis. There is weak evidence that a healthy diet, with reduced alcohol intake and increased physical activity, is associated with a lower risk of getting endometriosis.[12] A diet high in fruit, particularly citrus fruit, might lower the risk for endometriosis.[13]
Are there any other treatments for endometriosis?
Some symptoms of endometriosis, like painful menstruation, can be managed without medication. Additionally, chronic pelvic pain associated with endometriosis may be alleviated through pelvic physiotherapy and myofascial trigger point dry needling.
Some people may find that some of their symptoms of endometriosis, such as painful menstruation, can be non-medically managed. Some people with endometriosis develop chronic pelvic pain, which may be manageable with pelvic physiotherapy and myofascial trigger point dry needling.[6]
What causes endometriosis?
Endometriosis occurs when endometrium-like cells grow outside the uterus, which often leads to inflammation. The exact cause of this condition is still not fully understood by researchers.
The endometrium is the lining of the uterus. Endometriosis is caused by endometrium-like cells growing outside the uterus, usually accompanied by inflammation.[12] Researchers haven’t yet pinned down exactly why this happens.[14]
Update History
Standard FAQ update
major
Research written by
Edited by
Reviewed by
References
Examine Database References
- Oxidative Stress Biomarkers - Jennifer Mier-Cabrera, Mercedes Genera-García, Julio De la Jara-Díaz, Otilia Perichart-Perera, Felipe Vadillo-Ortega, Cesar Hernández-GuerreroEffect of vitamins C and E supplementation on peripheral oxidative stress markers and pregnancy rate in women with endometriosisInt J Gynaecol Obstet.(2008 Mar)
- Dysmenorrhea Symptoms - Nalini Santanam, Nino Kavtaradze, Ana Murphy, Celia Dominguez, Sampath ParthasarathyAntioxidant supplementation reduces endometriosis-related pelvic pain in humansTransl Res.(2013 Mar)
- Oxidative Stress Biomarkers - Abolfazl Mehdizadehkashi, Samaneh Rokhgireh, Kobra Tahermanesh, Neda Eslahi, Sara Minaeian, Mansooreh SamimiThe effect of vitamin D supplementation on clinical symptoms and metabolic profiles in patients with endometriosisGynecol Endocrinol.(2021 Jan 29)
- Dysmenorrhea Symptoms - Fariba Almassinokiani, Sepideh Khodaverdi, Masoud Solaymani-Dodaran, Peyman Akbari, Abdolreza PazoukiEffects of Vitamin D on Endometriosis-Related Pain: A Double-Blind Clinical TrialMed Sci Monit.(2016 Dec 17)
- Endometriosis-associated pelvic pain - James L Nodler, Amy D DiVasta, Allison F Vitonis, Sarah Karevicius, Maggie Malsch, Vishnudas Sarda, Ayotunde Fadayomi, Holly R Harris, Stacey A MissmerSupplementation with vitamin D or ω-3 fatty acids in adolescent girls and young women with endometriosis (SAGE): a double-blind, randomized, placebo-controlled trialAm J Clin Nutr.(2020 Jul 1)
- Pelvic Pain - Zhou IW, Zhang AL, Tsang MS, Xue CCVitamin D for primary dysmenorrhea and endometriosis-related pain - A systematic review of registered RCTs.PLoS One.(2025)
- Dyschezia - André Schwertner, Claudia C Conceição Dos Santos, Gislene Dalferth Costa, Alícia Deitos, Andressa de Souza, Izabel Cristina Custodio de Souza, Iraci L S Torres, João Sabino L da Cunha Filho, Wolnei CaumoEfficacy of melatonin in the treatment of endometriosis: a phase II, randomized, double-blind, placebo-controlled trialPain.(2013 Jun)
- Dysmenorrhea Symptoms - Khalajinia Z, Falahieh FM, Aghaali MThe Effects of Chamomile and Flaxseed on Pelvic Pain, Dyspareunia, and Dysmenorrhea in Endometriosis: A Controlled Randomized Clinical Trial.Iran J Nurs Midwifery Res.(2024 Nov-Dec)