How common is vulvar or vaginal lichen planus?
About 1 in 100 women have lichen planus of the mouth and half of those may have lichen planus of the vulva or vagina. However, since the vulva and vagina are "private areas" dentists who make the diagnosis of lichen planus of the mouth don't ask about the vulva and vagina and the woman herself doesn't know to ask. As a result, lichen planus of the vulva is only diagnosed in 1 of 4000 women. | 
