I have, with only two girls. Both were gf's, and dated both of them for about three years.
Random, casual sex with people you barely know is great, but raw-dog? No fucking chance. I could care less about getting a girl pregnant, that wouldn't be a problem. I could handle having a kid. But getting VD? No pussy is worth that. With all the shit that is out there, you have to be stupid, or suicidal.