Okay, this argument has gone on long enough.
I think I understand what he's trying to say, he's just not doing a very good job saying it. I think he's trying to say if you wait till you're married to try and have love with someone, you'll know them well enough to know if they have an STD or not, thus leading to a decline in the spread of STD's. The way you've been wording it makes it seem like like "I'm married, so I can't get STD's anymore!!!!1!2131!", next time try to catch misunderstandings like that.