This is possible when your vaginal secretions of blood and discharge become more acidic in pH. The natural vaginal flora is acidic in a healthy state but can become more acidic at times, for example towards the end of menstruation where there is more vaginal discharge along with the period blood. This is not necessarily a concern, but can also be a healthy sign of natural cleansing of the body! So in fact, not all women experience this discolouration of the pads.
We use eco-friendly dyes and have found that this can happen in those colors that have colour red in their spectrum: red, pink, purple – not the blue. The red colour is sensitive to acidity. We have been doing research on the dyes, while being firm to stay with eco-friendly and healthy dyes.