protected sexual contact is the way to prevent std transmission - not using mouthwash before and after performing oral on someone.
also making sure you and your partner have had proper std testing at the proper times is also a way to be sure neither partner has std's to worry about transmitting :)
be smart about sex, not believe the nonsense folks tout online on some forums!!!
grace
No. I mean if you give someone oral sex with mouthwash in your mouth then yeah probably, but no one is going to do that.