You seem to have this image fixated that anyone who is opposed to sex at such an early age is an overweight computer nerd who has pin-ups of Carrie Fisher and Natalie Portman all over his room.
Granted, that describes me to a tee, but that's not what's important here. Responding to attacks with attacks only offends the people who have remained civil toward the people who hold your position.
Stinkerhead.
As Mikus said, the greater majority of 14-year-olds are quite uninformed about sexually transmitted disease. Many of their parents refuse to talk about the subject to them (mine included). The fact that my school's sex education was during the Clinton administration didn't help.
5th grade: "This is the reproductive system. This is a penis." *wait for giggles to subside*
6th grade: "This is sex. Use a condom. Have fun."
7th grade: "This is sex. Don't do it until you're married."
Left me quite
The fact is, keeping sex within a marriage reduces the possibility of the spread of STDs. If person A has herpes, and is married and has sex with person B (it is quite possible to carry herpes without showing symptoms, so, yes, this could happen if there's no testing), then person B has herpes. It is contained.
If person A has sex with person B, C, and D over a period of x years, and then B, C, and D have sex with E & F, G & H, and I & J respectively, then you have spread the disease to quite a broader spectrum.
In addition, if a marriage was found on stable groundings (i.e., it will last), then it can also provide a much better environment in the case of an unexpected pregnancy. This is, of course, assuming that the two people were not in the passionate love stage of their relationship, in which case, their situation is little better than being born out of wedlock.