Some menstruators have found that their cup becomes a little stained after a number of uses, but it seems that the discolouration is related to the hormones and the unique natural chemical balance of each menstruator's vaginal fluids – some menstruators notice staining and others don’t. Some Ruby Cup users have even found that it is related to the Contraceptive Pill and a change in hormonal levels. Don’t worry if your cup becomes a little discoloured. Washing with lemon juice can sometimes help!