Think you can’t swim on your period? Think again. From cramp myths to tampon-string fears and even shark attacks (yes, really!), there’s a whole tide of misinformation out there about swimming while menstruating. But here’s the truth: swimming on your period is not only safe — it can actually help ease symptoms like cramps and fatigue. With the right period product (hello, Mooncup), there’s no reason to skip the pool, sea, or scuba session. Let’s dive into the facts and bust some persistent period myths once and for all.
Swimming makes your cramps worse
Low-intensity exercise, like swimming, has actually been proven to help relieve menstrual cramps. This is because it encourages your body to release endorphins, which can act like natural painkillers. What’s more, the buoyancy of the water can soothe back pain while being easy on the joints. Exercising ‘such as swimming’ when you’re on your period can also help give you more energy and studies have found it can help combat depression and symptoms of anxiety.
Ocean Swimmer Beth French, who swam the English Channel in 2012, switched to the Mooncup to help with cramps associated with using a tampon while swimming. Says Beth: “Swimming long swims with a tampon in ends up feeling like you have an iron bar in your lower gut and can cause cramps which are never good! So I switched to a Mooncup, which is much better as it is more malleable.”
Swimming on your period is unhygienic
Periods are perfectly natural! They are not ‘unsanitary’ and shouldn’t be treated as a biohazard. If you’re in a large body of water (whether that be the sea or a swimming pool) and your period does happen to start unexpectedly, then chances are it will be so diluted so it won’t even be visible.
To help put your mind at rest, an Olympic size swimming pool contains roughly 2,500,000 litres of water, whereas most people lose less than 80ml of menstrual blood during an entire period!
And as a final point to ease any concerns that swimming on your period could be ‘unhygienic’, many swimming pools are treated with chlorine in order to protect swimmers from anything that could end up in the water (yes, you’ve guessed it – that’s everything including urine, sweat and even faecal matter).
As with any other form of exercise, we recommend emptying your Mooncup before and after swimming. Check out our blog all about swimming while wearing a Mooncup.
People can tell you’re on your period when you’re in the pool
Periods are nothing to be ashamed of but even so, there’s no reason why anyone should be able to tell that you’re on your period while you’re swimming. Nobody will be able to tell you’re on your period at all unless you choose to tell them.
One benefit of using the Mooncup is that it is worn completely internally, which means you don’t have to worry about a pesky tampon string making an unwelcome appearance either. The Mooncup also holds up to three times more than a regular tampon, so you are able to swim for longer!
You’re more likely to get an infection if you go swimming on your period
Swimming on your period shouldn’t increase your chances of vaginal infection. There are, however, a few things to consider.
The chlorine used in swimming pools as well as the sediment in the sea may irritate the vagina or vulva (whether you are on your period or not). That’s why it’s recommended you always shower after swimming. If this is something you’re worried about, getting changed out of wet swimwear may also reduce the likelihood of irritation or infection.
Generally, the vaginal pH is acidic but, during menstruation the vaginal pH becomes more alkaline. Because of this, some people are more prone to getting a non-serious bacterial infection at this time – regardless of whether they are swimming or not. If you feel you may have an infection or have noticed any change to your vaginal discharge (change in smell, colour or consistency), you should get it checked out by a doctor or nurse who will be able to help.
The sharks will come for you!
It’s an old wives’ tale that sharks will be able to sniff out your period blood and come after you. According to Steve Kajiura of Florida Atlantic University’s Shark Lab the sharks don’t even want our blood! What they’re interested in is detecting amino acids in the water, such as those excreted by parts of marine animals that sharks are actually evolved to eat.
So, can you swim with sharks on your period? Marie Levine, founder and executive director of the Shark Research Institute, told Mother Jones: “I’ve been diving for decades and even got my period while underwater with a school of hammerheads. The sharks were not interested and I had to fin like crazy to get close to them.”
Okay, so you can swim on your period without fear of sharks or infections, it’s not unhygienic, no-one will be able to tell and your cramps may even be relieved! But…
You can’t scuba dive on your period, right?
Over to scuba diving #RealMooncupUser Lauren:
“Just wanted to let you know that I wore my Mooncup while diving several times a day for a few weeks, to depths of approx 18 metres, and it was absolutely fine. Cleaning it well on a remote island with no running water was more of an issue, but I managed! Thanks very much.”
So, why not go with the flow and enjoy a nice dip in the water – period or not!
Blog disclaimer
Our blog is intended to share information and ideas around periods, health, and sustainability. While we do our best to keep content accurate and up to date, things can change over time. The information here is not intended as medical advice — for any health-related concerns, please consult a qualified healthcare professional. For more information on our claims, please see our Claims Page, and for the most up-to-date product information, please visit our Product Pages.
