Period Underwear 101: How It Works, When to Wear It & When to Change
A simple guide to help you feel confident at every stage of your cycle.
If you’re new to period underwear—or tried a pair that didn’t work the way you hoped—this guide explains how high-quality period underwear functions and how to use it confidently.
How Period Underwear Works
Period underwear looks like regular underwear but contains multiple functional layers:
Instant-dry top layer:
Moves moisture away from your skin immediately.
Absorbent core:
Holds your flow securely throughout the day or night.
Leakproof barrier:
Prevents leakage, even under pressure (sitting, moving, sleeping).
Full-length gusset:
Extends where real flow travels, offering complete coverage.
When engineered properly, these layers work together to create a dry, comfortable, secure experience.
When to Wear It
Period underwear can be used:
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during the day
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overnight
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while exercising
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at work or school
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for travel
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as backup for cups or tampons
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postpartum
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for spotting or irregular flow
Its versatility is one of its biggest strengths.
How Long You Can Wear It
This depends on two things: your flow level and the absorbency of the underwear.
General guidelines:
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Medium flow: 6–10 hours
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Heavy flow: 4–6 hours
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Overnight: full night
If you have extra-heavy flow, you may want to change once during your heaviest day—just like you would with any absorbent product.
How to Know When It’s Time to Change
Signs include:
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the fabric feeling heavier
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moisture returning to the surface
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your standard “heavy hours” approaching
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visible saturation in the gusset
Trust what your body tells you—every flow is unique.
Can It Replace Pads and Tampons?
For many women, yes.
If your flow is medium, period underwear can replace disposable products entirely.
For heavy-flow users, it can be the main method part of the day and the preferred option overnight.
How to Wash It
Caring for period underwear is simple:
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Rinse with cold water.
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Machine wash cold with similar colors.
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Hang or lay flat to dry.
No special detergent needed.
Is Period Underwear Safe?
Always choose underwear made from:
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PFAS-free materials
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breathable fabrics
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certified safe components
This is especially important for sensitive skin.
The Bottom Line
Period underwear can be a comfortable, effective, and reliable option—when it’s made well.
With the right design, you can feel dry, supported, and confident throughout your entire cycle.