
Period Poop 101
Why does it hurt to poop on your period? Why do you poop while you’re on your period? Does pooping help with period cramps? These are some commonly asked questions that may have crossed your mind as a woman on your lady time.
Bowel movements during your menstrual cycle, also known as ‘period poops’ are both frustrating and common. One study reports that 73% of women have experience gastrointestinal symptoms during their menstrual cycle. Period poops can range from diarrhea to frequent bowel movements and/or constipation. While everyone’s body is different, here are some answers to your frequently asked questions on period poop.
Why Do I Poop More on my Period?
Just before your period starts, prostaglandins, also known as fatty acids, relax the smooth muscle tissues inside your uterus, helping it shed its lining. Prostaglandins have a similar effect on your bowels, resulting in more poop and potentially diarrhea (1).

Why does my IBS get worse during my period?
Patients with IBS are susceptible to higher rates of constipation during the luteal phase of their menstrual cycle. 50% of patients with IBS in a 2021 study reported abdominal bloating that impacted their day-to-day life during all phases of their menstrual cycle. The study concluded that premenopausal female patients with IBS become the most symptomatic during the menstrual phase of their cycle (2).
Does taking contraceptives affect my bowel movements?
As of now, there is not enough evidence to determine whether or not taking contraceptives impacts your bowel movements. In this 2020 study, researchers concluded that bowel movements varied throughout women’s menstrual cycles, with most women reporting discomfort on day one of bleeding (3).

Why do I have diarrhea a week period my period?
Premenstrual symptoms begin between one to two weeks prior to your period and may last up to seven days after the start of menstruation (4).
Is there a way to prevent diarrhea while on my period?
Diarrhea is the passing of soft stool and/or more than 3 bowel movements a day.
Treatment of diarrhea involves replacing lost fluid and electrolytes. Some foods that help restore electrolytes include:
- Broth and soups that contain sodium
- Fruit juices, soft fruits, or vegetables that contain potassium
- Over-the-counter rehydration solutions (5)
Why do I have constipation before my period?
Constipation prior to the beginning of a period is thought to be due to increased levels of progesterone, which can delay the transit of waste food travelling through the gut (6).
How can I prevent constipation?
There is no definite way to prevent constipation, but you may be able to reduce its occurrence or severity by drinking enough fluids, eating enough fibre, and exercising. The following changes may help relieve constipation:
- Avoiding or limiting fat
- Avoiding overuse of certain laxatives
- Limit alcohol consumption
- Eat foods with probiotics and prebiotics
- Increase your fibre intake by eating foods such as vegetable and fruits, whole-grain breads, cereals and pastas, legumes, and nuts and seeds
- Eating at consistent times
While bowel movements change during menstrual cycles, it is important to note that if life-impacting pain during periods, bowel movements or urination occurs, this may be a sign of endometriosis (7). Please consult your healthcare provider if any of these symptoms occur.
Track your bowel movements by using CDHF’s myIBS app. Here, you can track your symptoms, medications, food and drink and more! Use the daily journal feature to write down any additional information that may explain your symptoms (including the start and end date of your menstrual cycle).
References:
- https://health.clevelandclinic.org/why-do-you-poop-more-on-your-period/
- Pati, Girish K et al. “Irritable Bowel Syndrome and the Menstrual Cycle.” Cureus vol. 13,1 e12692. 14 Jan. 2021, doi:10.7759/cureus.12692
- Judkins, T.C., Dennis-Wall, J.C., Sims, S.M. et al. Stool frequency and form and gastrointestinal symptoms differ by day of the menstrual cycle in healthy adult women taking oral contraceptives: a prospective observational study. BMC Women’s Health 20, 136 (2020). https://doi.org/10.1186/s12905-020-01000-x
- https://flo.health/menstrual-cycle/health/period/diarrhea-before-during-period
- https://cdhf.ca/en/digestive-conditions/constipation/
- Wald A, Van Thiel DH, Hoechstetter L, Gavaler JS, Egler KM, Verm R, Scott L, Lester R. (1981) ‘Gastrointestinal transit: the effect of the menstrual cycle’. Gastroenterology. Jun;80(6):1497-500. PubMed PMID: 7227774
- https://www.who.int/news-room/fact-sheets/detail/endometriosis