Why do my period pants smell after washing?

If your period pants smell after washing, it’s usually due to trapped blood, bacteria, or detergent residue that didn’t fully rinse out. Even if they look clean, odors can linger in the absorbent layers if they’re not washed and dried properly.

Here’s a full breakdown of why it happens and how to fix it:

👃 Why Your Period Pants Might Smell After Washing

1. Blood Wasn’t Fully Rinsed Out

  • Menstrual blood contains protein and iron, which can cling to fabric and cause odor.

  • If you skip rinsing before machine washing, the buildup may remain in the absorbent layers.

2. Washing in Hot Water

  • Hot water can set stains and smells into the fabric.

  • It can also cook bacteria into the layers rather than remove them.

3. Too Much Detergent or Fabric Softener

  • Using excess detergent may trap residue in the absorbent fibers.

  • Fabric softener blocks the absorbent layers and locks in smells.

4. Washing with Other Clothes

  • Period pants need a deeper clean than normal laundry.

  • When mixed with other clothes, they may not get washed thoroughly.

5. Not Drying Properly

  • If the underwear stays damp, it creates the perfect environment for bacteria and mildew, which causes a sour or musty odor.

🧼 How to Get Rid of the Smell — And Keep It Gone

✅ Step 1: Rinse Right Away

  • Rinse your period pants in cold water as soon as you remove them.

  • Gently squeeze out the water until it runs mostly clear.

✅ Step 2: Soak in Vinegar or Baking Soda (Optional but Powerful)

  • Soak in a solution of 1 part white vinegar to 2 parts cold water for 30 minutes.

  • Or add ½ cup baking soda to a cold soak.

  • This helps neutralize odor and break down blood proteins.

✅ Step 3: Machine Wash with Care

  • Wash in cold or warm water (never hot).

  • Use a fragrance-free, mild detergent.

  • Skip the fabric softener completely.

  • You can add a bit of white vinegar to the rinse cycle to combat smell.

✅ Step 4: Air Dry Thoroughly

  • Hang dry in a well-ventilated area or in sunlight, which naturally kills bacteria.

  • Do not tumble dry—heat can damage the absorbent layers and trap odor over time.

🛍️ Odor-Resistant Period Underwear to Try

  • 🩲 NYX Collection – Offers reusable period underwear designed for breathability and easy cleaning.

  • 🩲 Thinx – Features anti-odor and moisture-wicking technology.

  • 🩲 Aisle – Known for sustainable, odor-fighting designs.

📝 Final Tip

If your period pants still smell after washing, try:

  • Using enzyme-based laundry detergent (great for breaking down proteins in blood)

  • Giving your pants a deep clean soak every few months

  • Making sure they’re fully dry before storing

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