Understanding gastrointestinal (GI) tract Endometriosis

The bowel or gastrointestinal (GI) tract is part of the digestive system designed to help our bodies absorb nutrients and fluids and remove waste. It is made up of a two-parts which involve a complex group of organs including the small bowel (duodenum, jejunum, and ileum) and large bowel (colon and rectum).


The small bowel connects the stomach to the large intestine; the large bowel connects the small bowel to the anus (the output in which we release stools).


The appendix is a small pouch which comes off the colon, located on the right side of lower abdomen. The cul-de-sac is the area between the bowel and the back of the uterus and vagina.

When we eat, our food passes down the oesophagus into the stomach where digestion begins. It then makes its way to the small bowel where our vitamins, nutrients and minerals are absorbed. The leftover then makes its way into the colon where water is absorbed and finally, the remaining residue, or what we call ‘waste’ is stored in the rectum where it is held in place by various nerves and muscles until we are ‘ready’ to pass it through the anus.

What is Gastrointestinal (GI) tract Endometriosis?

GI tract (bowel) Endometriosis occurs when Endometriosis is found either on the surface (known as superficial Endometriosis) or infiltrated deep inside the bowel wall and surrounding structures.


This type of Endometriosis is most commonly found affecting the lower part of the intestine (the sigmoid and rectum).


When Endometriosis is found in this area of the body, it can begin to disrupt the process of emptying the bowel.


How is bowel Endometriosis diagnosed?

This type of Endometriosis can be difficult to diagnose as sometimes the symptoms can be non-specific (meaning the symptoms are generalised and difficult to pinpoint). Many of the respective symptoms may also appear to be similar to several other health conditions, such as irritable bowel syndrome (IBS); acute appendicitis and Crohn’s disease. To further confuse matters, these other conditions can also co-exist with Endometriosis.

The diagnosis itself can sometimes be challenging because the only way to definitively diagnose the condition and its stage of progress, is by undergoing surgery. This is an invasive procedure.

Do I have bowel Endometriosis?

Similar to those with pelvic Endometriosis, symptoms of bowel Endometriosis can range from mild to severe and they are often intermittent in nature. They tend to worsen during menstruation, although some people, especially those within the later stages of Endometriosis (moderate - severe) can experience pain and symptoms outside of menstruation or even continuously throughout the month.

Conversely, bowel Endometriosis can also be asymptomatic – meaning some people may not know they have the condition usually until later on, when they may undergo a procedure for something else.

What are the signs to look out for?

Pain opening the bowels is the most common sign of bowel Endometriosis and in more extreme cases blood in the stools. The symptoms can vary from one person to another. Some may experience one or two symptoms whereas others may experience a combination of them.


The following symptoms are often associated with bowel Endometriosis (the list is not exhaustive) and include:


  • Pelvic pain

  • Changes in bowel habits (constipation, diarrhoea)

  • A dull ache to acute pain or cramping in the lower abdomen and/or back

  • Abdominal swelling

  • Pain during and/or after consuming foods

  • Pain associated with sexual intercourse

  • The feeling of needing to pass bowel movements more frequently or urgently than usual

  • The feeling of not being unable to empty your bowel completely

  • Passing blood in stools may suggest signs of endometriosis

If you are experiencing unusual pain that is stopping you from carrying out your usual daily activities like attending school or work, or if you have noticed changes around your periods and/or bowel habits, there is a chance you might have Endometriosis, or it could be the cause of something else.


It is important to tell your doctor as early as possible.

It's important to know...

When the bowel becomes affected by Endometriosis, the condition is usually found elsewhere, most commonly within the pelvis - meaning those experiencing symptoms of bowel Endometriosis may often also experience symptoms of Endometriosis affecting other areas in the body at the same time. Some people can have bowel Endometriosis without experiencing signs of the condition elsewhere, although this is less common.

Which tests will I find most helpful?

  • A Pelvic exam

  • Ultrasound scan

  • MRI

  • Colonoscopy

  • Surgery

more about these tests and what to expect.

What treatments are available?

Treatment for bowel Endometriosis is similar to that of pelvic Endometriosis. It can be helped with a combination of pain relief and anti-inflammatory medications (NSAIDs), pelvic floor physiotherapy, and alternative therapies such as acupuncture.


Hormone treatments used to limit, help regulate or temporarily stop your periods may also benefit.


However, for more severe cases, treatment of the Endometriosis may require surgical intervention, if other treatments are not effective. 

When is the right time to consider having surgery?

Your doctor may recommend surgery for different reasons, these may be:


  • When your symptoms are severe and medical treatments have not worked

  • When Endometriosis is limiting/stopping you from passing bowel movements.

What to expect during surgery 

When Endometriosis is found affecting the bowel, the affected area will often need to be ‘shaved’, or in some instances (depending on severity) part of the bowel may need to be removed as a disc or a bowel resection.


In these instances, a temporary stoma bag may be fitted for anywhere between two-six months (sometimes longer) to allow the bowel to heal, avoiding the risk of leaking from the repaired area.


Your doctor will discuss the available treatment options with you taking into consideration the severity of your symptoms, your age, medical history, and various other individual circumstances along with any possible side effects, risks, and complications.

The importance of seeking specialist help

Because of the complexities of Endometriosis, surgical treatment is preferably carried out by an accredited Endometriosis specialist's – meaning a gynaecologist and colorectal surgeon working together where required.


This is because not all gynaecologists are familiar with Endometriosis. Furthermore, not all surgeons are trained specifically in diagnosing and treating the condition.

Finding expert help early on can help prevent delayed or misdiagnosis, poor treatment, and inadequate care.

Meet Tanya: "I was told that endometriosis was common for people of my ethnic group and was common because I was young. I was never told that I’d be getting an ileostomy, I woke up with one completely shocked. I was gaslighted on my journey. I was told to have a baby at 25 believing that would cure my endometriosis. No one ever told me about how serious this disease could be. I was 13/14 when I started having periods. I only knew about it because my sister had started before me, and we briefly touched on it in school, but it was such a taboo. Girls in my school were bullied for having their periods. I started to realise something wasn’t right when I was 18 and started uni. I would have horrific period pains and felt like I couldn’t walk. I went to the GP and she initially gave me contraceptives and left me at that. I then worsened a few years later when I was fainting, vomiting, having heavy periods, sickness, all things that shouldn’t be associated with a period. All things that should be red flags to say something is wrong. I kept going back and forth to the GP, but kept being told everything was normal and my periods were normal. I was formally diagnosed when I was 27. I had a trans vaginal scan and endo showed up. I then had an MRI and a diagnostic laparoscopy to confirm. I broke down when I was told I had endometriosis. I didn’t know what to expect, but I wasn’t expecting to have an incurable disease, a lifelong disease, one with so many unknowns. I’ve had four surgeries for my endometriosis, and it came back within ten months. It’s relentless and felt never ending. Acceptance has been so hard. I have an ileostomy because of endometriosis, my whole appearance and how I see myself has changed. I’m fortunate to have amazing family and friends around me who have helped me through my hardest times. The only thing I can is embrace this change and I’m a true believer that everything happens for a reason. I’m also fortunate that my ileostomy has enabled me to be the healthiest I have been in years and to do things I struggled to do when my endometriosis was at its worst. All the emotions possible I experienced. You get a feeling of relief at being validated but then being terrified at surgery, medication, hormones, menopause, now knowing what’s coming next and how it will affect you. You experience the thought that surgery will bring you relief and will take it all away but that’s not always the case. Fertility is a massive one as well. No one can give you a definitive answer about fertility and it’s heart-breaking to feel like you’ve been left in limbo. My family and friends have helped me overcome any obstacles. Similarly, putting my story out there and sharing it with others on my social media platform has enabled me to connect with other women who suffer and be part of an amazing community I want others to know how much strength they can take from their journey and even though they may not feel it, their bodies are carrying them through so much and fighting an incurable disease. I want others to know they are not alone and there’s so many who can relate".


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