Medical grade silicon is very unfavorable platform for any yeast or bacteria to live. But there is still a chance that it’ll live and that’s why boiling won’t be enough.
Try these tricks:
- Boil the cup at least for 30 min in water with vinegar in it
- Freeze the cup at least for 15 hours in at least –15 celsius
- Soak the cup in 3% hydrogen peroxide
One of the trickiest part is the holes because they a good place for the bugs to live. So make sure you clean the holes with extra care.
It might be that even these tricks won’t do the work, so if you notice the infection returning after using the cup, you should buy a new one.
Make sure you use breathable underwear (materials such cotton or bamboo) and avoid washing your vulva too often. Don't use any soaps.