When endometriosis meets the bowel and bladder

Research is increasingly showing us that endometriosis doesn’t always stay within the reproductive system, writes Anja Christoffersen.

Endometriosis is often dismissed as “bad periods”. But for some people, it can mean planning life around the bathroom – and not just at that time of the month.

Impacting 190 million reproductive-age women and girls globally, endometriosis is a chronic, systemic, inflammatory disease. In Australia, this condition is estimated to affect one in seven women and people assigned female at birth.

Endometriosis is when tissue similar to the lining of the uterus – the endometrium – grows outside the uterus, triggering inflammation, chronic pain, scarring and, in some cases, other organ damage.

For Australian women, endometriosis takes an average of almost seven years to diagnose – meaning many people spend years being told they have irritable bowel syndrome (IBS), anxiety or “painful periods”. Historically, symptoms affecting periods, bowel function and pelvic pain have often been normalised or minimised – contributing to delays in diagnosis and treatment.

Until recently, laparoscopic surgery and biopsies were considered the gold standard for definitive endometriosis diagnosis – creating significant barriers to getting help. This is beginning to change with advances in imaging and pathology.

Emerging research suggests endometriosis commonly co-occurs with autoimmune diseases, and that immune dysfunction may contribute to its development. This has the potential to improve how endometriosis is diagnosed, treated and managed in future.

For many people, endometriosis does not stay neatly within the reproductive system. But symptoms like incontinence, or challenges with bowel or bladder function, are harder to speak about.

Bowel and bladder endometriosis can mimic symptoms of IBS, urinary tract infections (UTIs) or an overactive bladder. The Mayo Clinic notes that endometriosis can be responsible for pain with bowel movements or urination, changes in bowel or bladder frequency, bloating and nausea. And it all gets worse around your period.

If this experience sounds familiar, you’re not alone.

Endometriosis Australia reports that bowel endometriosis impacts 5-20 percent of people with endometriosis, with 80-90 percent of it occurring in the rectum and sigmoid colon – the bottom 20cm of your bowel.

If you experience severe pain during bowel movements or rectal bleeding during your period, this may suggest lower bowel endometriosis.

Common symptoms linked to bowel endometriosis include:

• Constipation

• Diarrhoea

• Bloating and gas

• Abdominal cramping

• Painful bowel movements

• Rectal pain

• Rectal bleeding, especially during a period

• Urgency or accidents

• Bowel symptoms that flare before and/or during menstruation

If you are experiencing any of these, speak to your GP or gynaecologist. Further investigation may involve gastroenterology, colorectal surgery or imaging, depending on symptoms.

With the bladder sitting so close to the reproductive organs, it’s no surprise that 20-50 percent of people with endometriosis have disease near the bladder and ureters (the tubes from the bladder to the kidneys). Less often, it can infiltrate the bladder muscle or ureters – around one to six percent of the time.

Bladder endometriosis may include symptoms like:

• Needing to pee more often

• Urgency

• Pain when peeing or as the bladder fills or empties

• Trouble fully emptying the bladder

• Blood in urine, especially around periods

• Recurrent UTI-like symptoms

• Flank/lower back pain if ureters or kidneys are affected

If you are having bladder symptoms with endometriosis, it’s important to get this checked with your specialist. If your ureters are squeezed or narrowed as a result of endometriosis, urine can begin backing up in the kidneys and require treatment. In some cases, this can occur silently without obvious symptoms, potentially damaging kidney function over time.

When endometriosis affects the bowel or bladder, the impact is not just pain. It can mean anxiety about accidents, avoiding food, intimacy or travel, and living with symptoms that can feel deeply embarrassing to explain. It’s important to talk about the bowel and bladder side of this condition, so we can destigmatise the full experience for many with endometriosis.

If your bowel or bladder symptoms follow your cycle or worsen around your period, they may be linked to endometriosis – and are well worth investigating.

This piece is general information only and is not a substitute for professional medical advice, diagnosis or treatment. If you're experiencing any of the symptoms discussed, please speak with your GP, gynaecologist or another qualified healthcare provider about your individual circumstances.