I Swear By Period Underwear and These Are the 9 Best Pairs on the Market (2024)

TL;DR

ModiBodi's Sensual Hi Waist Bikini is our favorite pair of period underwear due to the merino wool gusset, excellent absorbency, and lasting quality. For an affordable pair of period underwear, we reach for Bambody Absorbent Panty, which you can buy in singles or in multipacks.

Byrdie FYI

Our Top Picks

Material: Bamboo viscose, elastane, merino wool | Absorbency: Moderate to heavy | Size Range: 4–22 | Oeko-Tex Certified: Yes

ModiBodi was our first introduction to period underwear, and frankly made it hard to switch to other brands. What sets the brand apart is the merino wool gusset, which is soft on the skin, wicks away moisture, and controls odors without PFAS or other chemicals. We've used the same pairs for almost four years, and can say they have never left us with a leak. Plus, after regular wear and washing, the underwear are still in tip-top shape. Our favorite style is this high-waisted bikini—not only is the lace waistband pretty but it's extremely comfortable, too.

Material: Rayon, spandex | Absorbency: Light to moderate | Size Range: XXS–3X | Oeko-Tex Certified: Yes

We love how these period panties are affordable and conveniently available on Amazon. That doesn't mean they are worse quality though—the brand obtained the Oeko-Tex certification and don't intentionally use PFAS. The blend of rayon and spandex hold up well in the wash. The hiphugger style gives you more coverage, with the leak-proof gusset going all the way to the back.

Material: Cotton, spandex, nylon, polyester, bamboo cellulose | Absorbency: Super | Size Range: XS–4XL | Oeko-Tex Certified: Yes

If you're on the hunt for period underwear that'll keep you protected on heavy-flow days, we recommend this one from Goat Union. While liquid does take some time to fully absorb, we were impressed with how much liquid disappeared into the material without any leakage or stains. While the fabrics are soft and stretchy, the design features multiple seams, which might be a point of discomfort for some people. But given the absorption capabilities and affordable price tag, this underwear has our stamp of approval. The brand states that the materials in its underwear are certified by SGS and the Standard 100 by Oeko-Tex and their products have passed two PFAS lab tests.

Material: Cotton, elastic | Absorbency: Medium | Size Range: XS–2XL | Oeko-Tex Certified: Yes

If there's one thing everyone who menstruates has in common, it's likely a desire to be comfortable. Tight, restrictive clothing is an absolute no-no during that time of the month. For all who are sensitive to underwear styles that dig into your skin, limit movement, or have lots of seams, this one's for you. These ultra-comfy briefs are made of soft cotton and feature an elastic waistband. They absorb liquid quickly and are dry to the touch once everything soaks up. Although the gusset remained dry, we'd prefer if it was slightly longer for added leak protection. The brand states its underwear doesn't contain PFAS, and they regularly test for it. Be sure to handwash and lay flat to dry.

Material: Cotton, polyester, spandex | Absorbency: Light to medium | Size Range: 3XS–6X | Oeko-Tex Certified: Yes

Size inclusivity in the fashion industry still needs some improvement, but we'll give credit where it's due. TomboyX underwear ranges from 3XS to 6X, meaning most people with periods can find the right fit. As for the design, the bikini shape is standard, the fabric is soft and comfortable, and the thick elastic waistband helps it stay secure without feeling uncomfortably tight. Keep these undies long lasting by machine washing cold in a mesh bag and line drying.

We will say the absorbency advertised for this underwear is a bit confusing. The brand says it provides light absorbency but should hold up to 8 teaspoons of liquid—which would equate to pretty high absorbency. After evaluating this period underwear in the lab, we found that it soaked up roughly 5 teaspoons of fluid—still a decent amount, but not quite what the brand claims. The brand states they don't intentionally add PFAS to period underwear, and they have a robust quality assurance process to avoid the chemicals.

Material: TENCEL lyocell, organic cotton, spandex, recycled polyester, TPU, hemp | Absorbency: Heavy | Size Range: XXS–5X | Oeko-Tex Certified: Yes

Periods can be unpredictable overnight. Since we tend to move around more, leakage can be more of a problem. Whether period underwear is your primary form of period care or you just don't like the idea of using other methods while you sleep, we highly recommend checking out this pair for nighttime. The boxer style gives you full coverage from front to back. It comes with an added booster pad that you can slip inside for extra heavy days and sleep easy with up to eight tampons worth of protection. The blend of lyocell and organic cotton is soft and breathable. The brand states all materials are Oeko-Tex certified and lab tested for PFAS.

Material: Cotton, rayon, spandex, polyester | Absorbency: Medium | Size Range: S–XXL | Oeko-Tex Certified: No

Whether it's for comfort or breathability, many people seek out cotton underwear. If that sounds like you, you'll appreciate that this underwear is made of cotton with a blend of rayon, spandex, and polyester for durability and stretch. The material is breathable, the design is simple and effective, and the absorbance capability is solid.

Rael Period Underwear easily absorbed three tampons' worth of liquid during testing, but the gusset felt pretty thin, which made us nervous about using it on heavier days. And while we'd like to see the brand extend its size range, this is an excellent option for anyone looking to keep it simple and comfortable but still stylish. While the brand is not Oeko-Tex certified, it does say it does not intentionally use PFAS and they test for the chemicals before releasing the products.

Material: Nylon, lycra, cotton, spandex, carbon | Absorbency: Light | Size Range: XS–4XL | Oeko-Tex Certified: No

Not all period underwear is bulky—take this pair, for example. While the design is only sufficient for light days (which the brand makes clear), it's hard to believe thong underwear this soft and seamless has any true leak protection at all—but it does. The Knix Leakproof Thong absorbed one teaspoon of liquid quickly and without leaking. We love that this period thong comes in a wide range of sizes and colors. Knix isn't Oeko-Tex certified but it does test for PFAS and doesn't intentionally add PFAS to its products.

Material: Nylon, elastane, polyester, lycra | Absorbency: Medium | Size Range: XS–3X | Oeko-Tex Certified: No

It can be hard to feel sexy when you're on your period, especially when period underwear typically isn't. But this pair from Dear Kate is different. It features a lace waistband that gives a flirty flare, as well as incredible absorption capability (despite the brand only claiming medium absorbency). This underwear successfully absorbed three tampons full of fluid without leaking. When we added more liquid, we were pleasantly surprised to see it actually absorbed closer to five tampons' worth—no spillage in sight—it was one of the most impressive period underwear products we tested. The brand states there are no PFAS in the materials they use, though they are not Oeko-Tex certified.

FAQ

• Should you be concerned about period underwear possibly containing PFAS or "forever chemicals?"

  There's some controversy about period underwear containing PFAS (polyfluoroalkyl substances). Dr. Alyssa Dweck, who specializes in gynecology, says these "forever chemicals are widely used and long-lasting chemicals found in water, air, fish, and soil worldwide." They make fabrics waterproof and stain-resistant, which is why they might be included in period underwear.
  

  She explains the health effects are difficult to determine and may vary based on the timing and duration of exposure but could include concerns such as decreased fertility or increased high blood pressure in pregnant women, developmental effects or delays in children, increased risk of cancers, and interference with the body's natural hormones.

  According to Dr. Erica Montes, board-certified obstetrician and gynecologist, the vulvovaginal area has a weaker barrier function and easily absorbs anything that comes in contact, hence raising the concerns about PFAS in period underwear. Due to limited regulations, other menstruation products—like tampons and pads—can also contain these chemicals, so it's up to consumers to research a product before buying. Dr. Montes recommends looking for period underwear brands that test for PFAS and are certified by a third-party company like Oeko-Tex and Gots.

• How do you wash period underwear?

  Most period underwear products are machine-washable for easy cleaning. However, there are things you can do to make them last longer. It's best to first rinse them before throwing them in the wash, washing on cold and gentle, and air-drying. To play it safe, we always recommend looking at the care instructions on the tag.

• How long can you wear period underwear?

  How long you can wear period underwear depends on your menstrual flow and the absorbency level of the pair you're wearing. Once the underwear feels wet and uncomfortable—similar to when wearing a pad—it's best to change it.

Article Sources

Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.