Endometriosis Bowel Symptoms: Pain, Relief, and Surgery

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Endometriosis is a full-body inflammatory disease in which tissue similar to the lining of the uterus grows outside the uterus. Historically, it has been a misunderstood disease thought to affect mainly reproductive organs. However, endometriosis lesions have been found on every organ, including the bowels.

According to research from 2020, 10% to 12% of people assigned female at birth have endometriosis, and 5% to 12% of those people have bowel involvement. You don't need to have endometrial lesions growing on your bowels to experience bowel symptoms, such as constipation, diarrhea, pain with bowel movements, and more.

In this article, learn more about bowel endometriosis and bowel-related endometriosis symptoms.

Bowel Symptoms of Endometriosis

Endometriosis is generally thought of as a disease that causes infertility and painful periods. While these are both symptoms of endometriosis, they do not fully and accurately portray the disease's symptoms.

Endometriosis can affect any organ, leading to painful sex, pain unrelated to menstruation, painful urination, bowel symptoms, and more. This, in turn, may contribute to the notable delay in diagnosis that most people with endometriosis experience.

Gastrointestinal symptoms are fairly common in endometriosis and should not be overlooked.

Some bowel symptoms of endometriosis include:

Lesion Location and Associated Symptoms

You do not need to have endometriosis lesions growing directly on your bowels to experience bowel symptoms.

One study found that, compared to participants without endometriosis, people with endometriosis had significantly more severe gastrointestinal symptoms unrelated to the location of endometriosis lesions. The one exception was that people with bowel endometriosis lesions were more likely to have nausea and vomiting.

Another study found that irritable bowel syndrome (IBS) is more commonly diagnosed among people with endometriosis than among the general public, regardless of endometrial lesion location.

Nature of Bowel Endometriosis Pain

Endometriosis can cause significant pelvic and abdominal pain. However, the pain pattern, location, intensity, and duration differ significantly from person to person.

Sensation

The sensation of endometriosis pain may feel like:

  • Aching
  • Burning
  • Cramping
  • Pushing or squeezing
  • Stabbing
  • Waves

Frequency 

The frequency of endometriosis pain differs from person to person.

In one 2021 study, these four patterns of endometriosis pain were found:

  • Cyclical: Pain worsening around menstruation
  • Constant: Daily pain, all month long
  • Random: No consistency, intermittent pain that is unpredictable
  • Changing: A change in pattern, usually worsening or becoming more frequent over time

Location and Depth


Endometriosis lesions are found on the rectum and sigmoid colon in about 90% of bowel endometriosis cases. Bowel endometriosis lesions can be located on the following:

Bowel endometriosis lesions often present as one single nodule with a diameter greater than 1 centimeter (cm). However, endometriosis lesions can be any size, depth, and color.

Causes

Endometriosis is a complex disease, and there are multiple causes for bowel symptoms, including the following:

  • Inflammatory mediators: Compounds responsible for inflammation can lead to constipation, diarrhea, bloating ("endo belly"), and other bowel symptoms.
  • Bowel obstruction: In rare cases, deep endometriosis can grow into the intestinal wall, causing obstructions or narrowing, leading to bowel symptoms.
  • Pelvic floor dysfunction: The inability to coordinate pelvic floor muscles can cause constipation or diarrhea, pain with bowel movements, and more.
  • Dysfunction or dysregulation of nerves: Endometriosis lesions can irritate the nerves around the bowels, leading to bowel pain, pain with defecation, and issues with constipation or diarrhea.

Diagnosing Bowel Endometriosis

The only definitive way to diagnose endometriosis is through a biopsy. When performing a biopsy, your provider takes a sample of the affected tissue and sends it to a lab for a specialist called a pathologist to examine under a microscope and provide a diagnosis.

Hysterectomy May Not Treat Endometriosis

While once considered the most effective treatment for endometriosis, a hysterectomy (surgical removal of the uterus) may not be the best treatment for endometriosis, especially in cases of endometrial tissue growth outside of the uterus. Hysterectomy can help with heavy menstrual bleeding and painful periods in some people, but it is not right for everyone. If your surgeon recommends a hysterectomy for endometriosis, seek a second opinion.

Supplementary Testing

If your provider suspects bowel endometriosis, they may recommend various supplementary tests before surgery to assist in surgical planning. These tests might include:

Imaging Can Miss Endometriosis

Medical imaging such as MRI and TVUS cannot definitively diagnose all endometriosis. The tests will reveal the most deeply invasive lesions but not superficial endometriosis.

Complications During Surgery 

General gynecologists may leave bowel endometriosis untouched during excision surgery (surgery to remove endometrial lesions and surrounding tissues) to avoid complications. An endometriosis specialist who uses the excision technique should perform the surgery, especially with the prospect of bowel involvement. A colorectal surgeon may often present in cases where bowel involvement is highly suspected.

Complications can happen during any surgery, including surgery for endometriosis on the bowels. Complications can include the following:

  • Anastomotic leakage: Gut leakage when the surgical site is not sealed properly
  • Rectovaginal fistula: An opening between the vagina and the rectum
  • Pelvic abscesses: A collection of fluid in the pelvic region

Your surgeon should inform you of possible complications and also provide their complication rates based on previous surgeries.

Treatment Options for Relief

Excision surgery is the gold standard for diagnosing and treating endometriosis. However, excision surgery is not recommended or accessible to everyone. Your provider may also recommend certain medications or physical therapy to relieve endometriosis symptoms.

Excision Surgery

Excision surgery to treat bowel endometriosis may involve one or more of these surgical techniques:

  • Rectal shaving: The endometriosis lesion is "shaved" or cut out from the surface of the bowel. This technique is the least invasive and is appropriate for lesions less than 3 cm in diameter and less than 7 millimeters (mm) in depth.
  • Disc excision: A surgeon may cut out a portion of the bowel wall and staple the opening together. This technique is usually reserved for endometriosis lesions less than 3 cm in diameter that do not take up more than 60% of the bowel circumference.
  • Segmental resection: In this most invasive technique, a surgeon removes a section of the bowel and sutures the remaining sections together. This technique is only done for the deepest and most advanced endometriosis lesions.

Other Treatments

Most general gynecologists use the ablation technique of endometriosis surgery, in which endometriosis lesions are burned off. With this technique, deeper endometriosis may remain under the burned surface and cannot be confirmed by a pathologist, which is problematic in cases of deeper bowel nodules.

Some healthcare providers may prescribe medications to manage symptoms, including birth control and pain medications. These medications do not slow the progression of endometriosis nor reduce the size of endometriosis nodules. However, they may help reduce pain or other symptoms and improve quality of life.

Your provider may recommend pelvic physical therapy to help reduce pelvic pain, treat pelvic floor dysfunction, and reduce pain with bowel movements. This treatment method can improve symptoms and quality of life but does not address the underlying cause of endometriosis lesions.

Summary

Gastrointestinal symptoms are common with endometriosis, regardless of whether lesions are growing on the bowels. Excision surgery with an endometriosis specialist is the gold standard for diagnosing and treating bowel endometriosis. However, complications can occur, and you should receive full informed consent from your surgeon before deciding on the best treatment plan.

Frequently Asked Questions

  • Should you get a second opinion for bowel endometriosis?

    Yes. Most general gynecologists are not experienced enough to appropriately treat endometriosis on the bowels. Bowel endometriosis is best treated by an endometriosis excision specialist, sometimes in combination with a colorectal surgeon.

  • Where in the bowel can endometriosis occur?

    Endometriosis lesions can grow on the small intestine, large intestine, cecum, sigmoid, rectum, and appendix. It extends from the outer surface (serosa) toward the inner surface (mucosa). Superficial endometriosis may appear as a small lesion on the outer serosa; deeply infiltrating endometriosis can penetrate the mucosa and cause bowel obstructions.

  • How do you tell the difference between IBS and endometriosis?

    Endometriosis and IBS have similar symptoms. IBS is diagnosed based on symptoms and exclusion; endometriosis is diagnosed based on surgery and pathology. Therefore, diagnostic laparoscopy is the only accurate way to differentiate between IBS and endometriosis.

17 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Samani EN, Mamillapalli R, Li F, et al. Micrometastasis of endometriosis to distant organs in a murine modelOncotarget. 2017;10(23):2282-2291. doi: 10.18632/oncotarget.16889

  2. Habib N, Centini G, Lazzeri L, et al. Bowel endometriosis: current perspectives on diagnosis and treatmentInt J Womens Health. 2020;12:35-47. doi: 10.2147/IJWH.S190326

  3. Ek M, Roth B, Ekström P, Valentin L, Bengtsson M, Ohlsson B. Gastrointestinal symptoms among endometriosis patients--A case-cohort studyBMC Womens Health. 2015;15:59. DOI: 10.1186/s12905-015-0213-2

  4. Kotowska M, Urbaniak J, Falęcki WJ, Łazarewicz P, Masiak M, Szymusik I. Awareness of endometriosis symptoms—a cross sectional survey among polish womenInternational Journal of Environmental Research and Public Health. 2021;18(18):9919. DOI: 10.3390/ijerph18189919

  5. Schomacker ML, Hansen KE, Ramlau-Hansen CH, Forman A. Is endometriosis associated with irritable bowel syndrome? A cross-sectional study. Eur J Obstet Gynecol Reprod Biol. 2018;231:65-69. DOI: 10.1016/j.ejogrb.2018.10.023

  6. Drabble SJ, Long J, Alele B, O’Cathain A. Constellations of pain: a qualitative study of the complexity of women’s endometriosis-related painBritish Journal of Pain. 2021;15(3):345-356. doi: 10.1177/2049463720961413

  7. Brigham and Women's Hospital. Deeply infiltrative endometriosis.

  8. Machairiotis N, Vasilakaki S, Thomakos N. Inflammatory mediators and pain in endometriosis: a systematic reviewBiomedicines. 2021;9(1):54. doi: 10.3390/biomedicines9010054

  9. Raimondo D, Cocchi L, Raffone A, et al. Pelvic floor dysfunction at transperineal ultrasound and chronic constipation in women with endometriosisInt J Gynaecol Obstet. 2022;159(2):505-512. doi:10.1002/ijgo.14088

  10. Johns Hopkins Medicine. Endometrial biopsy.

  11. Rizk B, Fischer AS, Lotfy HA, et al. Recurrence of endometriosis after hysterectomyFacts Views Vis Obgyn. 2014;6(4):219-227.

  12. Center for Endometriosis Care. Endometriosis and bowel symptoms.

  13. Wolthuis AM, Meuleman C, Tomassetti C, D’Hooghe T, de Buck van Overstraeten A, D’Hoore A. Bowel endometriosis: Colorectal surgeon’s perspective in a multidisciplinary surgical teamWorld J Gastroenterol. 2014;20(42):15616-15623. doi: 10.3748/wjg.v20.i42.15616

  14. Chou D, Perera S, Condous G, et al. Shaving for bowel endometriosisJ Minim Invasive Gynecol. 2020;27(2):268-269. DOI: 10.1016/j.jmig.2019.11.012

  15. de Almeida A, Fernandes LF, Averbach M, Abrão MS. Disc resection is the first option in the management of rectal endometriosis for unifocal lesions with less than 3 centimeters of longitudinal diameterSurg Technol Int. 2014;24:243-248.

  16. Johns Hopkins Medicine. Endometrial ablation.

  17. Lee CE, Yong PJ, Williams C, Allaire C. Factors associated with severity of irritable bowel syndrome symptoms in patients with endometriosis. J Obstet Gynaecol Can. 2018;40(2):158-164. DOI: 10.1016/j.jogc.2017.06.025

By Sarah Bence
Sarah Bence, OTR/L, is an occupational therapist and freelance writer. She specializes in a variety of health topics including mental health, dementia, celiac disease, and endometriosis.