As long as there isn't anyone in the home (including your baby) who is immune compromised, our hard plastic flanges can be wiped completely dry in between pumping sessions and washed every 3-4 times. This is safe because human milk actively kills bacteria. We don't recommend putting our flanges in the refrigerator between pumping sessions because it can make them cloudy and oils and milk debris can bond to the plastic and become harder to clean.
The best way to wash the hard plastic flanges between use is to use warm water, a little dish soap, and a small, soft bottle brush. We recommend using a grease-cutting dish soap like Dawn Ultra Original (yellow ducks on the label). Air dry or wipe dry with a lint-free cloth.
Reviewed by Diana West, IBCLC
June 10, 2021