In the past year or so, period pants have gone from a relatively niche product to an increasingly popular and widely available option in the UK.
The washable and reusable absorbent pants are a low-waste alternative to disposable pads, towels and tampons, and first made waves online via brands such as ModiBodi, Thinx and Wuka.
These versions can cost upwards of £25 per pair, though cheaper versions are beginning to appear as they become more mainstream.
Modibodi and Wuka recently launched cheaper ranges starting from £12, and high street chains Primark and M&S have got in on the action, launching their own cheap period-proof underwear for £12 or less.
But even at this price, period pants are a bit of an investment, considering you'll need a few pairs on the go.
We surveyed period pant users to find out how Primark and M&S period underwear compares, as well as how pricier pants are rated, to help you decide which ones are worth buying.
We asked people who'd tried Primark's period pants, and those who'd tried M&S period underwear (some had used both), whether they thought the brands were good for factors such as comfort, durability, and value for money.
Based on a December 2021 survey of 563 period pant and menstrual cup users. No. of respondents - Primark (176), M&S (168)
Perhaps unsurprisingly, given the low price and the fact that period pants in general are quite expensive, those who'd used Primark's period undies were more likely to praise them for value for money than users of any other brand we reported on.
However, whether they truly represent good value is debatable, as the low price point seems to come at the expense of their overall performance in other areas.
Only a quarter of Primark's customers said they thought the undies looked good, and they were less likely than users of any other brands to say the undies were durable, or were good for leak protection. They had the second-lowest proportion of users rating them as comfortable too.
For M&S users, the biggest plus was comfort - 79% of users said they found the pants comfortable. But, like Primark's users, fewer of them were impressed with the look of the pants.
Overall, M&S hovered around the middle of the pack in comparison to the seven other period pant brands we got feedback on.
Given that they're more moderately priced than many rivals (£12 per pair / £9 in multi-buy), they're a good option to try if you don't want to spend too much but want to give period pants a go.
Where to buy:
But, with OG period pant brands launching cheaper ranges, it's worth seeing how other options are rated too.
Period pants may take some getting used to if you're new to them, but according to our survey, it's certainly worth giving them a try, as the overwhelming majority are converts:
Comfort was the biggest benefit for people, with respondents telling us they felt they could move around more and feel more confident on their period while wearing them.
A few said they wished period pants had been an option when they were younger, and that they've bought them for teenage daughters as an easier option than changing pads at school or remembering to bring spares.
The main drawback for people was that they didn't feel fresh when wearing them - but only 15% of respondents said this was the case.
How sustainable are period pants?
After comfort, people's second favourite thing about period pants was that they reduce waste.
With increasing awareness around the toll that disposable - and often plastic-based - sanitary products can take on the environment, a desire to cut down on single-use products has driven the meteoric rise of reusable options like period pants and menstrual cups.
Look out for:
Many brands give a lifetime estimate of around two years, meaning one pair of period pants could replace approx 360 disposable tampons or towels.**
However, there's an increasing range of alternatives to consider too, including menstrual cups, which can have a longer lifetime, though they may take a bit more getting used to.
**Everyone's flow is different, but this assumes approx three disposable products per day over five days a month for two years.
Prices correct as of 18 February 2022