Cleaning a menstrual cup involves two levels of care: a quick wash each time you empty it during your period, and a thorough sterilization by boiling between cycles. Both steps matter. Research published in Applied and Environmental Microbiology found that simply rinsing a cup with water leaves behind a layer of bacteria that builds up over hours and resists removal without heat. Here’s how to keep your cup safe and in good shape.
Cleaning During Your Period
Every time you remove your cup to empty it, wash it with warm water and a mild, unscented soap before reinserting. Fragrance-free soap is important because perfumes and dyes can irritate vaginal tissue and degrade silicone over time. If you’re in a public restroom without access to a sink, wiping the cup with unscented toilet paper or rinsing it with a bottle of water works in a pinch. Just give it a proper soap-and-water wash at your next opportunity.
One spot that’s easy to overlook: the tiny air holes near the rim. These holes help with suction and seal, and they can get clogged with residue. To clean them, fill the cup with soapy water, place your palm flat over the opening, and squeeze. The pressure forces water through the holes and pushes debris out. You can also use a soft-bristled toothbrush or a toothpick (gently) to clear anything stuck.
Sterilizing Between Cycles
Once your period is over, a soap wash alone isn’t enough. Boiling the cup is the most reliable way to kill bacteria and break down the biofilm that forms on the surface during use. Bring a pot of water to a rolling boil, submerge the cup completely, and let it boil for 5 to 10 minutes. Don’t exceed 10 minutes, and don’t let the cup rest against the bottom of the pot where direct heat could damage it. Some people place the cup inside a wire whisk or a mesh ladle to keep it off the bottom.
Several brands also sell microwave-compatible sterilizing containers. You fill the container with water, place the cup inside, and microwave it for 3 to 4 minutes. This works just as well as stovetop boiling and is more convenient if you want to sterilize quickly.
Lab research has shown that the bacterial biofilm left on a menstrual cup after simple water rinsing is significant, even after multiple rinses. Boiling is what actually removes it. Some researchers have even recommended using two cups per cycle so you can boil one while wearing the other, though most people manage fine with a single cup and thorough sterilization between periods.
Silicone vs. TPE Cups: Different Rules
Most menstrual cups are made from medical-grade silicone, but some are made from thermoplastic elastomer (TPE). The cleaning process differs slightly between them. Silicone can handle temperatures up to 200°C, so boiling poses no risk whatsoever. TPE cups tolerate heat only up to about 120°C, which means boiling still works, but you need to be more careful about timing. Keep TPE cups in boiling water for the shorter end of the range (closer to 3 to 5 minutes) and watch that the water stays at a gentle boil rather than a vigorous one.
There’s also a difference with soap. Silicone cups can be washed with mild soap during daily use. TPE cups are more chemically sensitive and shouldn’t be cleaned with soap or detergent. For TPE, stick to plain water during your cycle and rely on boiling for sterilization. Always check the care instructions from your specific brand, since formulations vary.
Removing Stains
Discoloration is normal and doesn’t mean your cup is dirty or unsafe. Over time, most cups develop a brownish or yellowish tint from contact with blood. If the appearance bothers you, soak the cup in a 3% hydrogen peroxide solution, mixed with equal parts water, for no longer than 8 hours. Rinse thoroughly afterward. Hydrogen peroxide at this concentration is mild enough for medical-grade silicone but effective at lifting stains.
For more stubborn spots, make a paste with baking soda and a small amount of water. Gently rub it over the stained areas with your fingers, then rinse until all the gritty residue is gone. Baking soda is mildly abrasive, so don’t scrub aggressively or use it every cycle. It’s a periodic deep-clean tool, not a daily habit.
Managing Odor
A slight smell after wearing the cup all day is normal. If your cup develops a persistent odor that doesn’t go away after a regular wash, boiling usually solves it. The heat breaks down the organic material causing the smell. For lingering cases, the baking soda paste method described above can also help neutralize odors. Soak the cup in a diluted baking soda solution for a few hours, then rinse well with clean water.
A truly foul or fishy smell that persists after boiling could indicate a bacterial issue with the cup itself (tiny cracks or surface degradation can harbor bacteria) or a vaginal infection worth looking into. If the cup material looks pitted, cracked, or sticky, it’s time to replace it.
What Not to Use
Certain cleaning products will damage your cup or irritate your body. Avoid dishwashing liquid, antibacterial soap, rubbing alcohol, bleach, and any scented cleanser. These can break down silicone, leave chemical residue, or disrupt vaginal flora. Vinegar is sometimes suggested online but can degrade silicone with repeated use. Stick to the basics: mild unscented soap for daily washes, boiling for sterilization, and hydrogen peroxide or baking soda for occasional deep cleaning.
Storage Between Cycles
After sterilizing, let the cup air dry completely before storing it. Most cups come with a breathable cotton or fabric pouch, and that’s the ideal storage option. The material allows air circulation and prevents moisture from getting trapped. Never store your cup in an airtight container, a plastic bag, or a sealed box. Trapped moisture creates the kind of warm, damp environment where bacteria and mold thrive. Keep the pouch somewhere clean and dry until your next cycle.