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Reusable period knickers are the latest lingerie innovation and could revolutionise your underwear drawer. Here, M&S lingerie expert Mhairi Leach explains how they work. Explore our range to find the perfect pair of period pants 

Why use period pants?

The benefits of using period knickers are becoming more and more apparent, with their popularity growing rapidly over the last few years. Not only are they a convenient way to keep dry and protected during your monthly cycle but wearing reusable period pants might cut down on the amount of single-use period protection, such as tampons, heading to landfill. Did you know that the average person uses an around 11,000 disposable menstrual products in their lifetime*, costing around £130 a year**?

Our range of period underwear has something for every flow, whether you need light just-in-case protection or something for heavier days. You can wear leak-proof underwear by itself on the lighter days of your cycle, or in tandem with a tampon or menstrual cup to give you added peace of mind when your flow is heavy. Period knickers are also a great choice for coping with post-birth bleeding and often more comfortable than wearing a bulky maternity pad. And, as another plus, they look and feel just like your everyday underwear, too. 

“Our moderate-absorbency knickers hold up to 12ml of moisture, the same as four light tampons or two regular towels, and the high absorbency holds up to 20ml of moisture – which is almost double an overnight pad or super tampon,” says Mhairi Leach, technology lead (lingerie).

These low-rise bikini briefs combine style and function with a high level of absorbency to give you the confidence you need to get on with your day.

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How do period knickers work?

Our period knickers have three layers of protection to keep you comfortable and dry 24/7. The top is made of patented fabric that has moisture-wicking properties to draw liquid away from your body. The patented high-absorbency middle layer can absorb up to 20ml of liquid, neutralising any odours to keep you feeling fresh. Finally, there’s a waterproof layer to stop any leaks. Plus, the gussets on all our period knickers have been extended, to ensure that there is no leakage around the sides.

We recommend trying out the different absorbencies to see which one best suits your flow. High-absorbency full briefs are perfect for heavier days and come in range of colours and styles.

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How to wash period underwear

You can wash period pants with the rest of your everyday laundry (up to 40 degrees) either in the machine or by hand. Line dry afterwards for added eco points. “We suggest a quick rinse and then pop them in the washing machine on a delicate wash cycle. Don’t use fabric conditioner as this can affect the absorption,” says Mhairi.

Our range of period knickers comes in a choice of colours and styles, including high-leg, full briefs and bikini styles and you can also buy multi-packs of pants in a mixture of absorbencies, so you’ll always have a pair to suit your needs. This multi-pack of everyday period knickers in comfortable cotton modal is a great starting point for your new regime, with three pairs in a flattering high-leg design. All our cotton is responsibly sourced.

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Words: Sarah Lafarge

* Based on a Statista survey of 24,024 people who used sanitary towels as feminine-hygiene products in the UK from 2013 to 2020.

** According to Channel 4 News FactCheck, based on the charity Bloody Good Period’s estimation that the average lifetime cost of having a period is about £4,800 per person.

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