Actually, if anything you're probably safer going to the mouth than the pussy. The mouth has lots of measures to deal with bacteria and the like, the vagina is much more susceptible to infection.I don't dislike the idea of fucking a girl like that, actually I've done it a few times to a girl in some wild nights.
However, I can't stop thinking of all the bacteria in the intestines that should not be going inside a woman's pussy let alone her mouth...
Do you girls ever take any pre-post measures ?
Not that I'd say either is safe, just that one is less hazardous than the other.