Period underwear for heavy bleeding
We deserve better
Why choose period underwear from Flow?
After two fertility treatments and two births, I no longer wanted to use menstrual products that went inside my body – I wanted to be able to bleed in peace.
That was the beginning of Flow – the first period underwear on the Danish market.
Today, we make period underwear with a focus on comfort, quality, and responsible production – created by people who menstruate themselves.
✔️ Soft, skin-friendly materials
✔️ Different absorption levels
✔️ Comfort like regular underwear
✔️ A more environmentally friendly alternative to disposable products
Our mission is to make menstruation freer, safer, and less complicated — without compromising on style or function.
Sincerely, Cathrine
What we are most proud of
5 great reasons why you'll love us
THE HEART IS ALWAYS FIRST
We are also here to create greater changes than just in your everyday life.
Our founder changed Danish legislation in 2021 by having the age limit on frozen eggs removed.
In 2025, we created the Red Flag campaign, which ensured the Danish women's national handball team the right to wear dark shorts during the World Championship. And we will continue.
SAFETY AND SECURITY IMMEDIATELY AFTER
Despite the lack of legislation and safety requirements for menstrual products in the EU, we do not shy away from our responsibility. We do not use PFAS, nano-silver - no magical "stay fresh" treatments of the absorbent layers. We third-party test our underwear for chemicals and use innovation without compromising your safety to solve odor issues.
PREMIUM PRODUCTION
We produce in Portugal, Denmark, Lithuania, and Turkey – always using the best materials such as organic cotton, organic merino wool, and ECONYL®.
Our partners are the best in their respective fields, and several of our factories are GOTS-certified, which ensures high standards for employee welfare.
BY PEOPLE WHO MENSTRUATE, FOR PEOPLE WHO MENSTRUATE
We create products we ourselves need - and test them thoroughly (so yes, they are tested with real menstrual blood). In addition, we have a test panel consisting of hardcore and dedicated members from our community who take the task seriously.
MORE THAN MENSTRUATION
We know. It's about much more than menstruation. It's about a changing body - throughout the entire cycle, month after month.
That's why we are redefining what 'period products' are beyond a practical solution. The best-rated absorbent underwear, yes, but also care that supports you and your body throughout your entire cycle.
That's Flow Cycle Routine.
FAQ
How long do period panties last?
The general expectation for the lifespan of socks and underwear is about 3 years. These are garments that wear out and are used every day.
Since we don't add chemical treatments to the pad, no function will degrade.
If you take good care of your period panties and wash them according to instructions, the quality of our period panties is so good that you can easily use them for 3 years or even longer.
Here you can find our guide on how to best care for your period panties.
How do I choose the best fit for me?
We have menstrual panties that fit different bodies - whether you prefer a low rise, mid rise or high rise fit.
The Period Flow Brief and Period Flow Shorts both have a high waist, which is loved by many for the feeling of a hug around the belly.
Period Flow Cheeky has a more sporty look but with a wide and soft elastic at the waist - it is mid-rise.
Then we also have the classic low-waisted fit , which is a super nice, basic menstrual panty if discretion under the panty hem is *your thing*.
How long can I use them at a time?
It depends on your flow and your cycle day - as well as the absorbency of the panties.
But changing your menstrual panties at least morning and night is good hygiene - think of your absorbent underwear just like pads and tampons. They need to be changed every now and then.
But unlike tampons, for example, you are not at risk of Toxic Shock Syndrome, as menstrual panties are a non-invasive menstrual product.
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