Bowel Endometriosis Symptoms: Signs, Tests and Treatment

Quick answer: what are the symptoms of bowel endometriosis?

The main bowel endometriosis symptoms are pain when you poop, diarrhea around your period, constipation and a swollen belly. These gut symptoms often get worse around your period, and many people also have bad period pain or pain during sex.

Bowel endometriosis is easy to mistake for irritable bowel syndrome (IBS). A clear diary of your symptoms and your cycle helps your doctor see the pattern and send you for the right tests.

What is bowel endometriosis?

Endometriosis is tissue like the lining of the womb growing in other places. It is often found around the womb, ovaries and pelvis, and it sometimes affects the bowel. The bowel is the most common place for endometriosis outside the reproductive organs.

The lower end of the large bowel, where the sigmoid colon joins the rectum, is the part most often affected. The patches can sit on the outer surface of the bowel or grow deeper into its wall. Endometriosis that grows deep into the bowel, bladder or ureter is called deep endometriosis.

Estimates of how many people with endometriosis have it on the bowel range from about 4% to 37%. The range is wide because studies classify it in different ways, and many cases are never diagnosed.

Common bowel endometriosis symptoms

Symptoms vary a lot from person to person. Gut symptoms that come with your period or follow your cycle, in particular pain when you poop, are a reason to think about endometriosis.

Gut symptoms

Signs that endometriosis may be on your bowel include:

• Pain when you poop: pain in your rectum or pelvis when you have a bowel movement. Doctors call this dyschezia. It is one of the main signs, in particular when it comes with your period.
• Diarrhea around your period: loose or frequent poops that come with your period.
• Constipation: hard poops or going less often.
• Bloating: a swollen or distended belly.
• Blood in your poop: some people notice rectal bleeding that comes with pain. Never assume blood is from endometriosis. See the red flags below.
• Pain when sitting: discomfort when you sit for a long time, or pain that spreads to the area between your vagina and anus.

Other endometriosis symptoms

Bowel endometriosis rarely comes alone. Endometriosis in other places can cause:

• severe period pain that stops you from doing your normal activities
• pain in your lower belly and back
• pain during or after sex
• pain when you pee
• extreme tiredness (fatigue)
• difficulty getting pregnant

Our list of 20 endometriosis symptoms covers the wider picture. If your belly swells up a lot around your period, see our guide to endo belly.

Bowel endometriosis or period poops?

Many people have looser poops and some cramps on their period, and that alone does not mean endometriosis. If your main problem is pain when you poop during your period, our guide to a painful bowel movement during your period explains the common causes and what helps at home.

Think about bowel endometriosis when the pain is severe, comes back with every cycle, also happens at other times of the month, or comes with bad period pain, pain during sex or trouble getting pregnant.

Why bowel endometriosis is mistaken for IBS

IBS and bowel endometriosis share the same main symptoms: belly pain, diarrhea, constipation and bloating. In one population study, women with endometriosis and women with IBS had no clear difference in their gut symptoms, which makes the two hard to tell apart. Almost 3 in 10 of the women with endometriosis also reported IBS.

You can also have both. People with endometriosis are about twice as likely to have IBS.

Other conditions with similar symptoms include inflammatory bowel disease, diverticulitis, appendicitis and bowel cancer. When doctors do not think of endometriosis, people can go a long time with the wrong diagnosis and wait longer for the right treatment.

Timing is the best clue. If your gut symptoms follow your cycle month after month, tell your doctor, even if you were told it is only IBS. The endometriosis symptom quiz can help you put your symptoms in one place before your visit.

How bowel endometriosis is diagnosed

A doctor will ask about your symptoms and may offer a pelvic exam and an ultrasound scan. A scan through the vagina can find deep endometriosis on the bowel, bladder or ureter, and it helps rule out other causes.

To check how far deep endometriosis has spread, doctors use a specialist ultrasound or a pelvic MRI scan, read by someone trained in endometriosis imaging. A normal scan does not rule out endometriosis. A laparoscopy, where a surgeon looks inside your belly through a small cut, can confirm it.

Bowel endometriosis is best managed by a specialist team, and the UK and European guidelines agree on this. Under the NICE guideline, anyone with suspected or confirmed deep endometriosis on the bowel should be referred to a specialist endometriosis centre with access to a colorectal surgeon who has an interest in endometriosis. The ESHRE guideline also advises referral to a centre of expertise for deep endometriosis.

Our guides on how to get diagnosed with endometriosis and getting a referral to an endometriosis specialist walk through each step.

Treatment for bowel endometriosis

There is no cure for endometriosis yet, but treatment can ease the pain and gut symptoms.

• Painkillers: a 3-month trial of paracetamol (acetaminophen) or an NSAID, such as ibuprofen, is a common first step.
• Hormone treatment: the combined pill, progestogens, GnRH agonists or GnRH antagonists can reduce endometriosis pain. Progestins can ease pain when you poop, along with period pain and pain during sex.
• Surgery: a surgeon can remove endometriosis from the bowel. The options are shaving the patch off the bowel wall, cutting out a small disc of bowel, or removing a short section of bowel. Shaving has the fewest complications. Removing a section of bowel is kept for large or deep patches, and complications such as leaks where the bowel is joined back together are more common after it.

The right choice depends on where the endometriosis is, how deep it goes, how bad your symptoms are and whether you want to get pregnant. Ask your surgeon about the benefits and risks before any operation. For more on each option, see our endometriosis treatment options guide.

When to see a doctor

See a GP or OB-GYN if:

• you think you might have endometriosis
• your symptoms affect your everyday life, work or relationships
• you have had treatment but your symptoms have not got better, or are getting worse

Also see a doctor if you have had blood in your poop for 3 weeks, your poop has been softer, thinner or longer than normal for 3 weeks, or you have lost weight for no reason. Bleeding from the bottom is sometimes a sign of bowel cancer, so get it checked even if you think it is endometriosis.

Get urgent help the same day if your poop is black or dark red, or you have bloody diarrhea.

Go to the emergency department or call your local emergency number if you are bleeding from your bottom non-stop, or there is a lot of blood, such as red toilet water or large clots.

What to track for your doctor

Bowel symptoms that follow your cycle are easy to dismiss in a short appointment. A few months of notes make the pattern clear. Give your doctor as much information about your symptoms as you can.

Track these each day:

• Cycle day: the day of your cycle, and when your period starts and ends.
• Bowel symptoms: pain when you poop, diarrhea, constipation, bloating and any blood.
• Pain score: how bad the pain is on a scale of 0 to 10.
• Stool type: what your poop looks like. A Bristol Stool Chart can help.
• Other symptoms: period pain, pain during sex, pain when you pee and tiredness.
• Medicines: what you took and whether it helped.
• Daily life: days you missed work, school or plans because of your symptoms.

Before your visit, write down your three most important symptoms and your questions. Bring someone with you if that helps you remember what was said. The free printable food and symptom diary has a row for each meal, with bowel movements and cycle day.

Related guides

• 20 Symptoms of Endometriosis and What the Pain Feels Like
• Painful Bowel Movement During Period: Causes and Relief
• How to Get Diagnosed With Endometriosis: Tests and Referral
• Do I Have Endometriosis?
• Endometriosis Tracker App - Endolog

Track your bowel symptoms with Endolog

The Endolog endometriosis tracker app lets you log bowel symptoms, pain and your cycle in one place. You can then share a clear report with your doctor.