Sizing for inverted nipples definitely can make it more difficult to find the best flange size. There are varying degrees of inversion, even between breasts on the same person, that determine how much of an issue it may be.
Inverted nipples that can stay inverted after being gently pulled out can usually work for pumping. Try gently pulling on them for a few seconds or minutes before applying the flange and then you should be able to pump normally. Follow our article "Which flange size will fit me best?" to find your size.
Nipples that can't be pulled out at all can work less well with flanges because they can't get the stimulation needed to make the milk flow well. It may take some trial and error and help from our inhouse lactation consultants to find out what works best for you but between our Sizing Guarantee and our return policy there's no risk in trying.
If you're not sure which type of inverted nipples you have or you need more guidance, just reach out to us and our inhouse lactation consultants will be happy to help.
See also Getting Deeper in Silicone Flanges
Reviewed by Diana West, IBCLC
June 10, 2021