“Period underwear” may have once been defined by the old pairs you didn’t mind subjecting to possible leaks or stains during your cycle, but now, it’s a whole category of period care products that truly put those in the past. With absorbent gussets and leakproof layers, period panties do the work of traditional pads, but they are reusable and look no different from other undies.
As Kim Rosas, founder of?Period.Shop?and?Period Nirvana, points out, “Bleeding into your underwear has always been a thing, intentionally or not.”
Sure, you might prefer using tampons or a menstrual cup to keep your flow contained, but you’re probably wearing underwear along with those too, so why not add an extra layer of assurance?
And a number of brands are leaning into the category with intention, creating period underwear for all bodies on the size and gender-identity spectrums. From lacy bikinis that promise leakproof protection to boxers made for free-bleeding, you would never even guess that they are period products. “Since they are truly just like underwear there is no disruption to your day,” Rosas says.
Ahead, we speak to women’s health experts about the benefits of period underwear, how to care for them and the 13 best pairs to try.
How does period underwear work?
“Period underwear are worn the same way as your regular underwear, and today they can be found in every single style — seamless, boxer, high-rise and even thong,” Rosas shares. “Your mileage will vary based on the style, absorbency and, of course, your own flow, but each pair has an absorbent core (sometimes topped with a layer of fabric for comfort or moisture wicking) and almost always has a layer of waterproof material between the outside layer and the absorbent core.”
Like with traditional pads, the goal is to keep the wearer feeling fresh and dry, even when your flow says otherwise. Also similar to other period products, choosing the right absorbency level will help you avoid any leaks.
“There are period underwear options for all levels of flow,” says Dr. Sophia Yen, the co-founder and CEO of Pandia Health, the only women-founded, women-led, doctor-led birth control delivery service. Some are made to be a substitute for panty liners on the lightest days, and others can absorb up to 10 regular tampons’ worth of blood. It’s all about what works with your own routine. “They are also good to use as a backup for a tampon or instead of a panty liner if you find you have general discharge not during your period,” Yen adds.
Dr. Somi Javaid, board-certified OB/GYN and founder and chief medical officer of HerMD, notes that period underwear can be a great option for teens especially. “Young menstruators who don’t like the feeling of a pad, or there’s fear or just inability to comfortably insert a tampon, or they worry about changing tampons at school — I’ve seen them really adapt to this the quickest. They love them as a choice,” she says.
Javaid also points out that the technology behind period underwear is now being used in other apparel like activewear and swimwear, so you can have peace of mind on your period in any scenario.
How do you clean period panties?
Each brand will have its own washing instructions, so be sure to consult the care tag. Typically, if you bleed into a pair, you’ll want to rinse them with cold water, either right after changing them or right before you throw them in the washing machine.
“Many brands are line-dry only, so it’s important to know that. Tumble drying can shorten the life span of what are pretty spendy products,” Rosas points out.
And while some may be able to get by with a single pair per day, “Realistically, most period underwear should be changed throughout the day to maintain optimal comfort, freshness and peace of mind,” says Suzanne Siemens, founder of period care brand Aisle.
The important thing to remember is that, “if there’s moisture against the skin, and it’s no longer being pulled away, then you want to change it,” Javaid says, adding that she recommends keeping a travel pouch with an extra pair with you, just in case you need to change them.
What to know about period underwear and PFAS
Unfortunately, it’s a fact that chemicals are a part of most period care products, and in recent years, period underwear has come under scrutiny for being contaminated by PFAS (per- and polyfluoroalkyl substances). “It’s unclear how much exposure [to PFAS] people get over time,” Javaid says. “The levels are not currently regulated, [and] they’re found in tampons … pads and panty liners. So, exposure is generally unavoidable.”
PFAS are considered “forever chemicals” because they do not easily break down and they have been flagged by the US Environmental Protection Agency as being linked to a variety of adverse health effects, including decreased fertility, increased risk of certain cancers, hormonal disruption and more.
The chemicals have been commonly used in consumer products as a liquid repellent. Because they are prevalent, they can inadvertently contaminate products during manufacturing or shipping. After PFAS were found in period underwear company Thinx’s products in 2020, the brand, and many others in the industry, have taken active steps to test for possible PFAS exposure and publicly share the findings.
For now, you can safely shop period underwear by researching brands and checking out their FAQ pages for more information on how they are addressing PFAS.
Best period underwear to shop
Rosas says that Aisle’s organic period underwear is in her usual rotation and that the brand “gets extra points for having a very inclusive line in both styles and sizes for everyone with a period.” Yen is also a fan of the brand’s variety for different absorbencies. The Boost Boxer is a bestseller that offers full-coverage protection and, like the rest of the Boost line, an additional absorbency booster insert, so it’s great for heavy flows.
“Worn on their own, they absorb up to four tampons of menstrual flow,” Siemens says. “Each pair comes with a Boost Insert that doubles the absorbency to eight tampons as needed. Extra inserts can be swapped in throughout the day, which allows you to wear the same pair of underwear all day in comfort.”
Siemens’ personal favorite style is Aisle’s Boost Brief, which comes in several colors. “[They] have a super-stylish high-rise coverage front and back and feel buttery soft, thanks to a perfect blend of organic cotton and Tencel,” she says.
“Switching to period underwear is liberating because it rejects the wasteful and costly burden of relying on disposable single-use pads and tampons,” Siemens adds. “Period underwear is an explicitly more sustainable choice compared to disposables. The average menstruator will dispose of over 11,000 pads and tampons in their lifetime, many of which will take over 500 years to biodegrade.”
In addition to fan-favorite menstrual cups, Saalt has a great lineup of period underwear styles, and the brand is a favorite of Rosas'. With mesh and lace details, Saalt’s period underwear feels like it belongs in the lingerie drawer.
Saalt does testing to ensure its products are free of PFAS, which is one of the reasons why Javaid recommends its period underwear as well.
I personally love Proof’s seamless styles. The leakproof thong is a favorite in place of a traditional liner on light days or as a backup during workouts since it is virtually invisible under yoga pants.
Proof also makes period underwear specifically for teens. This pair is geared toward light days or dealing with other puberty-related growing pains like spotting, discharge and sweat.
From seamless silhouettes to lace-backed undies, Knix has a pair to match any mood. And the brand doesn’t stop with period underwear. Knix has a variety of period-friendly swimwear, leggings and shorts and teen-friendly styles.
Available in sizes 3XS to 6X, Tomboy’s inclusive period boy shorts provide leak protection for light flows or incontinence. For heavier days, the style features a floating gusset that makes it easy to tuck away pad wings.
TomboyX’s collection of period underwear is made with Oeko-Tex 100 Certified fabrics, which screens for chemicals in the textiles, so you can be assured they are free of PFAS.
Rosas also has her eyes on this new brand offering boxer-style undies. “Now that there are more inclusive styles available, period underwear is a great product for trans and nonbinary people,” Rosas says. “Having a period can invoke feelings of gender dysphoria and depression. Using underwear that is no different in feel can help alleviate those feelings.”
Monthly’s underwear is made for all menstruating bodies, and the absorbent material is great for light or regular days, or as backup.
Committed to keeping period care accessible and affordable, The Period Company’s $9 menstrual underwear is worth stocking up on. The brand has several styles available for under $10 in cotton, microfiber and sporty stretch material.
Cora’s bikini-cut period underwear is great on its own, but it’s also the perfect sidekick to the brand’s collection of other period care products. From organic cotton tampons and pads to reusable period products like menstrual cups and discs, it's all about what fits in with your own routine.
I’ve been wearing Thinx for several years, and they do exactly what period underwear is supposed to: minimize waste by being reusable and keep the wearer dry and leak-free. Whether used as backup or for free-bleeding, the Classic Hiphuggers have held up month after month.
Since 2020, Thinx’s underwear has been tested for harmful chemicals under the safety requirements of the Standard 100 by Oeko-Tex.
Aerie’s soft and stretchy cotton period underwear is made for light to medium days. They’ll keep you feeling dry without any of the bulkiness some period underwear packs.
Providing coverage equivalent to four to five regular tampons, Rael’s high-waisted period panties provide extra comfort and support for the areas that need it most during your cycle.
