How to know when period underwear is full?

A Practical Guide to Staying Leak-Free and Comfortable

Period underwear is a game-changer for many people looking for reusable, eco-friendly menstrual care — but one question often comes up:
👉 “How do I know when my period underwear is full?”

Unlike pads or tampons, period underwear doesn’t have a visual indicator, so here’s how to tell when it’s time for a change.

🩲 1. Pay Attention to the Wetness Sensation

Most high-quality period underwear (like NYX Collection’s 4-layer period panties) are designed to wick moisture away from the skin.
However, once they’ve reached capacity, you may begin to feel:

  • A slight dampness or wetness

  • Less dryness compared to earlier in the day

That’s your body’s way of telling you the absorbent core is full.

⏱️ 2. Track How Long You’ve Worn It

As a general rule:

Flow Type Change Every...
Light 8–12 hours
Medium 6–8 hours
Heavy 4–6 hours

If it’s been longer than these windows — especially on a heavy day — it’s probably time for a fresh pair.

💧 3. Check for Leaks or Seepage

If you notice:

  • Leaks onto clothing

  • Moisture on the sides or edges

  • A visible stain on your pants

It’s time to change. High-quality period underwear shouldn’t leak unless it’s overfilled or not the right fit.

🩸 4. Match Absorbency to Your Flow

Each brand lists absorbency levels — from light flow (1 tampon’s worth) to super absorbent (4 tampons’ worth).

✔️ If you bleed more than the underwear can hold, it will fill up faster.
Check the product specs — for example, NYX Collection’s Medium Flow underwear holds around 2–3 tampons worth of blood.

🛍️ Recommended Brands with Clear Absorbency Guidelines

  • NYX Collection – Clear flow categories, leak-proof layers, and breathable design

  • Thinx – Offers absorbency labels (Light to Super)

  • Modibodi – Great for overnight and postpartum use

  • Aisle – Transparent about how many ml each product holds

💡 Bonus Tip: Keep a Backup Pair

Always bring a clean pair when you’re out — just in case. A zip pouch or wet bag works great for storing used ones on the go.

✅ Final Thoughts

You’ll know your period underwear is full when:

  • It starts to feel damp

  • You see light leaks or spots

  • You’ve worn it for the max recommended time

Trust your body and routine — and don’t be afraid to change a little early to stay comfy.

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