Period Diarrhea with Endometriosis or Adenomyosis
Loose stools and sudden urgency that flare just before and during your period can be a sign of endometriosis or adenomyosis, especially with cramping, pelvic pain or painful bowel movements. Chemicals released with your period can loosen stools for many people, but with endometriosis the effect can be stronger and more painful.
- How common
- Common
- When
- Just before and early in your period
- Often with
- Cramps, urgency or pelvic pain
Medically reviewed by Dr. Steven Vasilev, MD
Board-Certified Gynecologic Oncologist & Integrative Medicine Diplomate, Advanced Robotic Endometriosis Excision Surgeon, Director of Lotus Endometriosis Institute · Updated Oct 2026
When it flares
It often builds in the days before bleeding and peaks in the first days of your period. Diarrhea that doesn't follow your cycle still deserves a check.
Does this sound like you?
Tap any that fit. We'll turn them into a note you can bring to your visit.
None of these? If your diarrhea worries you, it's still worth a conversation. Speak with us
When to get help
Diarrhea that comes back with your period is reason enough to see an endometriosis specialist, even if you've been told it's IBS.
Keep track
For two or three cycles, note the cycle day, how often and how urgently you go, any pain or blood, and foods or medicines that set it off. It's the most useful thing to bring to your first visit.
Speak with Us
Book a visit if it:
- Comes back with your period
- Comes with pelvic pain, painful bowel movements or painful sex
- Comes with heavy periods or trouble getting pregnant
- Gets in the way of work, school or plans
- Keeps coming back after you were told it's IBS
Your first visit
We go through your history and your notes, then map out next steps together, whether that's tests, imaging or treatment.
When it needs a specialist: Bowel endometriosis surgery
What it feels like
How patients often describe it
- I have to run to the bathroom, again and again.
- My bowels feel like they're spasming.
- It comes in waves, with cramps each time.
- I'm afraid to leave home on my period.
It often comes as sudden urgency and loose stools in waves, with cramping low in the pelvis or deep in the rectum. A sharp pain can build before you go, ease, then return with the next wave. Some people only have loose stools on their period; others have a sensitive gut all month that gets worse with it. Severe diarrhea can leave you dehydrated.
Why it happens
Prostaglandins and your period
During your period, prostaglandins, hormone-like inflammatory chemicals, rise. They can speed up the bowel and draw fluid into it, so stools turn looser and more urgent. This happens to many people without endometriosis. With endometriosis, inflammation can make the same effect stronger and more painful, even when no endometriosis grows on the bowel.
Endometriosis on or near the bowel
Endometriosis that grows on or into the bowel, most often the rectum and sigmoid colon, can bring urgency, cramping and diarrhea that swings with constipation. Patches nearby can irritate the bowel and the nerves that control it, and scar tissue and tight pelvic floor muscles can add to the swings.
Adenomyosis
Adenomyosis grows into the uterus's muscle wall, not onto the bowel. But a uterus that is inflamed and cramps hard can irritate the bowel nearby, bringing urgency and loose stools around your period. It often comes with endometriosis, and people with both report more cycle-linked bowel changes.
“Diarrhea that returns every cycle with pelvic pain is a clue worth following, not something to just live with. We look at the bowel, uterus and pelvis together, even if you've been told it's just IBS.”
Why it's often missed
Diarrhea around your period is common, so it's easily put down to hormones, IBS, food intolerance or stress. IBS and endometriosis can also occur together, so an IBS label doesn't rule endometriosis out. What points further is the pattern: diarrhea that comes back with your period alongside pelvic, bowel or sex pain, or heavy periods.
Tests can look normal too. A colonoscopy checks the bowel's inner lining, while endometriosis usually sits outside or in the wall.
How it's diagnosed
Track two or three cycles
Note the cycle day, how often you go, any pain or blood, and possible triggers. Diarrhea that lines up with your period is an important clue.
Rule out other bowel causes
Infections, IBS, inflammatory bowel disease, celiac disease and food intolerances can look alike. Stool and blood tests help, and bleeding may call for a colonoscopy.
An exam and focused imaging
A pelvic exam and an ultrasound or MRI aimed at deep endometriosis can show disease near the bowel. A normal scan doesn't rule it out.
See an endometriosis specialist
A specialist puts your pattern, exam and imaging together, and can confirm and treat endometriosis with laparoscopy, with a bowel surgeon when needed. Bring your notes.
Treatment options
Treatment depends on what's driving your diarrhea, and often combines several approaches.
- Medical
Hormonal therapy
Quiets the cycle, which can mean fewer period-linked flares for some people, though responses vary.
Hormonal Therapy - Medical
Symptom relief
Short-term antidiarrheals, antispasmodics or, when they fit, bile acid binders, chosen with your doctor.
- Surgical
Excision surgery
Removes endometriosis at the root, which can improve diarrhea when disease on or near the bowel drives it.
Surgery overview - Support
Pelvic floor therapy
May help when diarrhea swings with constipation, or comes with painful bowel movements or rectal pressure.
Pelvic Floor Therapy - Support
Flare care
Fluids with electrolytes, small bland meals for a day or two, and reviewing NSAIDs or magnesium with your doctor.
Integrative Medicine
Diarrhea that follows your cycle?
We look at your bowel, uterus and pelvis together to find what's driving it.
Schedule a ConsultationPrefer to talk it through? Call or text us.
Questions people ask
Can endometriosis cause diarrhea only during your period?
Yes, endometriosis can be associated with diarrhea that happens only during your period. Inflammation can intensify period-related bowel changes even without bowel wall involvement, but diarrhea alone does not establish that endometriosis is the cause.
Can adenomyosis cause diarrhea?
Yes, adenomyosis can be associated with diarrhea for some patients, especially around their period. It stays within the uterine muscle, but inflammation and cramping can trigger loose stools; endometriosis or bowel sensitivity may also contribute.
Why do bowel symptoms get worse during my period?
Bowel symptoms can worsen during your period because hormonal shifts and prostaglandins affect gut movement and pelvic nerve sensitivity. This can happen without endometriosis, but endometriosis-related inflammation and scarring may intensify symptoms.
How is period diarrhea different from IBS?
Period diarrhea tends to worsen before or early in your period, while IBS symptoms often fluctuate with stress, sleep disruption, and certain foods. When cycle-linked diarrhea comes with significant pelvic pain, we consider endometriosis as well as IBS.
What can I do now for period diarrhea?
For period diarrhea, prioritize hydration, adding electrolytes if you’re going frequently, and eat small, bland meals for a day or two. Pause anything that seems to trigger symptoms, and track whether NSAIDs for cramps worsen diarrhea after dosing.
Often happens with
Sources & medical review
Reviewed by Dr. Steven Vasilev, MD, Board-Certified Gynecologic Oncologist & Integrative Medicine Diplomate, Advanced Robotic Endometriosis Excision Surgeon, Director of Lotus Endometriosis Institute. Last reviewed Oct 2026; next review Oct 2027.
- Bernstein MT, Graff LA, Avery L, Palatnick C, Parnerowski K, Targownik LE. Gastrointestinal symptoms before and during menses in healthy women. BMC Womens Health. 2014;14:14.
- Luscombe GM, Markham R, Judio M, Grigoriu A, Fraser IS. Abdominal bloating: an under-recognized endometriosis symptom. J Obstet Gynaecol Can. 2009;31(12):1159–1171.
- Ferrero S, Camerini G, Ragni N, Venturini PL, Biscaldi E, Remorgida V. Norethisterone acetate in the treatment of colorectal endometriosis: a pilot study. Hum Reprod. 2010;25(1):94–100.
- Brunoro MM, Servidoni ACP, Wakabayashi SDN, et al. Coexisting adenomyosis in endometriosis: similar pain and quality of life, with longer bleeding and bowel symptoms—a comparative cross-sectional study. Int J Gynaecol Obstet. 2026;175(1):164–173.