Gut Health in Endometriosis?
Is it Endo or IBS? Or Is It Both? Understanding the Connection Between Endometriosis and Irritable Bowel Syndrome
Written by Dr. Fiona Callender, ND
Bloating, pain, changes in bowel consistency… these are symptoms that are frequently exerperienced by those with irritable bowel syndrome (IBS) as well as those with endometriosis. Understanding the cause is important for how a patient receives a diagnosis and appropriate treatment.
The connection
IBS and endometriosis frequently co-occur - this is well established in medical research. Those with endometriosis have about a 2- to 3-fold increased risk of also meeting criteria for IBS. This is huge. Rates for IBS can be as high as 52% in some studies. As many as 90% of those with endometriosis experience some form of digestive symptoms. We’ll get into why this is the case, but we know the relationship seems to run in both directions - a fairly large proportion (up to 30-40% in some studies) of those diagnosed with IBS may be subsequently diagnosed with endometriosis.
Endometriosis and IBS share some overlapping symptoms, contributing to missed diagnoses
Both conditions can present with bloating, abdominal/pelvic pain, constipation, and changes in bowel habits. Because we know so many of those with endometriosis present with digestive concerns, endometriosis is frequently misdiagnosed as IBS. This can contribute to significant diagnostic delays. Diagnostic delays are a huge problem for patients with endometriosis as pain becomes more chronic and more challenging to treat over time. It’s important to remember that having one diagnosis does not rule out the other.
In fact, the two conditions share underlying biological mechanisms.
There are a few mechanisms that have been proposed/studied to understand the connection:
Visceral hypersensitivity - the nerves in the pelvis and gut become more sensitive to pain signals, so normal sensations (like gas or stool moving through the bowel) are perceived as painful. We all produce gas and have food move through our system, usually without any sensation. Those with both IBS and endometriosis tend to feel these physiological events as painful.
Central sensitization - the brain and spinal cord amplify pain signals over time, lowering the overall pain threshold in the body. This means that even small stimuli can be perceived as big pain.
Chronic low-grade inflammation - both conditions may involve ongoing, subtle inflammation that can irritate nearby organs and nerves.
Mast cell activation - there is more research coming out about mast cell involvmenet. These immune cells in the gut wall release chemicals that increase pain and alter bowel function. It’s possible that this is at play for some folks with IBS symptoms.
Gut microbiome changes (dysbiosis) - alterations in gut bacteria may play a role in some aspects of both conditions.
Endometriosis lesions can also be positioned directly on the bowel - leading to symptoms
Endometrial-like tissue can implant on or near the intestines, causing symptoms that mimic, or genuinely trigger, IBS-type complaints. Often this is worsened by that visceral hypersensitivity we mentioned above. Even those with minimal or mild lesions on the bowel, can have very strong or intense GI symptoms relative to the severity of endometriosis due to that sensitivity in the nervous system.
Understanding that symptoms might overlap is important for treatment
Overlooking the impact of either condition can lead to delays in support or improper treatment. Treating IBS and failing to recognize an endometriosis diagnosis can lead to delay in getting appropriate care - especially if the patient is trying to build their family. By a similar token, approaching digestive concerns in a patient with endometriosis as purely related to lesions, might mean unnecessary surgery if we don’t take into account possible co-existing IBS. Taking into account your whole symptom picture and treating based on your experience, but also your goals, is important.
It’s very common to experience digestive symptoms when you have endometriosis, but we still need to assess them and treat you appropriately. Often the nervous system is playing a role in amplifying some of these symptoms but these symptoms are very real - it’s not all in your head. You deserve a comprehensive assessment that looks at your whole symptom picture.