It is a universally accepted fact (it is, isn't it?) that when you're on your period, you poo more. This is a given, just like the cluster of hormonal spots residing on your chin and the slightly-irrational-but-it-doesn't-feel-like-it paranoia.
It's hardly surprising that as one thing gets moving down there (your uterus), it makes another (your bowels) do the same. But that's not very scientific is it? Luckily, YouTube channel Gross Science has explained exactly what makes this happen, along with a couple of other pressing questions like what actually is in period blood and whether we're the only mammals who menstruate.
So why do we poo more when we're on our periods?
Apaprently it's to do with two chemical functions: prostaglandins which are chemical signals that make the uterus to contract in order to push out the lining (which is what your period actually is). These same signals can sometimes make their way into the bowels, causing them to contract too, and make you need to go.
Progesterone is another reason. This hormone helps maintain a pregnancy and has a slight constipation effect, but when you're on your period, the levels are lower meaning you could need to poo more.
Watch the video for the full explanation and answers to some other period-related questions.
Like this? You might also be interested in:
Study Calls For More Research Into The Impact Of Periods On Women's Lives
Ask An Adult: What Happens To My Body The Week Before My Period?
Follow Chemmie on Twitter @chemsquier
This article originally appeared on The Debrief.