If you've ever noticed that you tend to poop more when you are on your period, fear not: you are not alone. Sometimes referred to as "period poops", it's fairly common for people to find themselves needing to go more often, or else experience diarrhea, even if it isn't something that is commonly talked about. "Period diarrhea is the WORST," gynecologist Dr Jennifer Gunter tweeted in 2019. "It's due to the prostaglandins that are released. I learned that in medical school when I was 20 and I so wish I'd known it when I was 14. Knowing WHY your body is doing something is so helpful even if medically doesn't fix anything." What causes period poops? "Lots of women experience this phenomenon," science communicator Anna Rothschild explained in a video in 2016. "And for that you can probably blame two chemical signals: prostaglandins and progesterone." The cramping pain you experience before or during your period is also due to prostaglandins, which are chemicals made in the lining of your uterus. Before you write it off as a bad chemical jerk, prostaglandins have a use beyond just causing pain. The chemicals cause your blood vessels to contract and triggers contractions in muscles in your uterus, and you start shedding your uterine lining. High levels of prostaglandins can cause especially painful period cramps, by making the uterus contract more strongly. But these high levels can also run havoc in your bowels and intestines, making them contract as well. "Also progesterone, which is a hormone that helps you maintain a pregnancy, is slightly constipating," Rothschild explains. "But levels of it drop during your period, so it lets things loosen up down there." Essentially, a lack of progesterone makes you more likely to experience looser stools, while high levels of prostaglandins can make your bowels contract, working together to increase your bowel movements. Not everybody experiences period poops, and it is, unfortunately, more likely to occur in people who already experience painful cramps (due to the underlying elevated levels of prostaglandins). If you do get it them, it's more likely to be at the beginning of your period, when levels of the chemicals are high. An increase in poops can also be due to dietary changes around your period, with studies showing an increase in calories taken in during the phase just before your period. Ibuprofen, while having the benefit that it kills pain, also has the added benefit that it lowers levels of prostaglandin in your blood, and so may reduce this symptom. Source
