text: what causes vaginal dryness? can switching birth control pill cause vaginal and mouth dryness? if not, what could it be? as far as i checked, i don't have any std, unless there is something that went unnoticed... and my period is normal, so premature ovarian failure or menopause are not likely. i've never had this problem before. birth control can be one of the problems.  here's a link to tell you more.