I think legionaireX has a point. There are plenty of good reasons for abstinance. (I can't spell, if that is right its just a guess.) STD's suck. Right now, AIDS is threatening to be a worldwide crisis. It takes a while to detect, a lot of people who have it don't know, and its deadly. Of course you could have yourself and your partner checked before you ... eherm... but most people don't do that.
The only 100 percent safe way is to simply not have sex.
Not to mention pregnancy... There is no fail safe, couples who use condoms and the pill have still gotten pregnant. Hell, even a girl who was born without a vagina got pregnant. And if that doesn't stop it, I don't know what will.