What Causes White Patches On The Inner Labia?

I just noticed white patches on the inner labia. It started yesterday with a little bit of itchiness. It was only red and irritated then. Slowed down with the itchiness this morning until now I looked and there are white patches around that area. The are not on the outside but closer to the middle of everything. Any ideas? Since it is the weekend I have not been able to get a hold of my doctor and will first thing Monday morning.