How Does Period Underwear Work—And Does It Actually Work?

Spoiler alert: Yes, it does. Really well, actually.

If you’ve been curious about trying period underwear but have questions like “Will it leak?” or “Can I wear it all day?”—you’re not alone. Whether you're new to reusable period products or you're looking for an alternative to pads and tampons, period underwear is a game changer that’s becoming a favorite among gynecologists, moms, teens, and eco-conscious women alike.

Let’s walk through exactly how period underwear works, how much it can hold, and why so many are making the switch to Pixie Period Underwear—the leakproof, ultra-comfy solution designed for real bodies and real flows.

What Is Period Underwear and How Does It Work?

Think of period underwear as your favorite pair of underwear with superpowers. It’s made with built-in absorbent layers that are designed to trap menstrual fluid, wick away moisture, and prevent leaks, all without the need for pads or tampons.

At Pixie, our period underwear features:

• A soft, organic cotton gusset (the part that touches your skin)
• A moisture-wicking top layer to keep you dry
• A high-absorbency core to lock in flow
• A leakproof outer layer that keeps your clothes protected
  

It’s like wearing regular underwear… that just happens to absorb up to 5 tampons worth of fluid.

Not all period underwear is created equal. Some brands include PFAS (a harmful “forever chemical”) in their materials. Make sure to research what materials are used when looking for your new favorite period underwear. Pixie proudly offers period underwear with no added PFAS or other harmful chemicals, because your period protection should be safe for your skin and the planet. 

Does Period Underwear Really Work?

Yes. In fact, gynecologists, such as those quoted in Teen Vogue like board-certified OB‑GYN Melanie Bone, recommend period underwear as a comfortable, convenient, eco-friendly alternative to disposables.

At Pixie, we designed our midrise, seamless, bikini fit period underwear to be worry-free:

• Holds up to 5 tampons’ worth of fluid
• BloatFit™ technology stretches up to 5 sizes—so your underwear moves with you and you stay comfy even on bloated days
• Designed for every flow, from light spotting to heavier days

Plus, Pixie’s leakproof period underwear is ultra-thin, flexible, and made for real movement—whether you're sleeping, running errands, or sitting in a meeting all day. This means on your period you can still be you, but with less bulk and no worries. 

Can You Wear Period Underwear All Day?

Yes, you can. Most people wear period underwear for 8–12 hours before changing. That said, it depends on your flow. On heavy days, you may want to have a backup pair just in case.

You can also wear certain period underwear overnight. Overnight period underwear typically has a padded gusset that will go higher up in the back to prevent leaks through the night. Make sure to read up on your period underwear to see if it was designed for overnight.

Pro tip: The moisture-wicking layers help keep you dry, even as fluid is being absorbed.

Who Should Use Period Underwear?

Short answer? Anyone with a period.

Ideal for:

• Teens just starting out (no insertion or awkward pads)
• Busy adults seeking low-waste protection
• Postpartum users or those managing discharge or bladder leaks
• People with sensitive skin wanting organic cotton gussets and clean materials

Check out our Pixie period care for teens or explore reusable options like our Pixie Cup or Disc if you’re interested in mixing protection styles.

How Do You Wash Period Underwear?

To keep your underwear sanitary and absorbent follow these instructions: 

• Rinse in cold water after use
• Machine wash cold on a gentle cycle
• Hang dry (no dryer, heat, bleach, or fabric softeners!)

With proper care, each pair can last 2–3 years, replacing hundreds of disposable products.

Why More People Are Making the Switch

• No pads. No waste. No worries.
• All-day protection without harsh chemicals
• Gynecologist-backed credibility for safety and comfort
• Stretchy, flattering fit for bloated days and beyond
• Eco-friendly + cost-saving cycle after cycle

Still Unsure? Try It for Yourself.

Curious whether period underwear is worth it? Give it a try. We stand by every pair with a 100% Satisfaction Guarantee. If it’s not a fit, we’ll refund or replace it—no questions asked.