I think it should be increased, probably to 18, same as smoking and drinking. It may not help much in the long run, but I do know some people would not do it because of the age limitations. In my opinion if you can stop even one person, then the law has worked.
Realistically, sex isn't something a child should be having. Some places having it as low as 12 or 13, and it makes no sense to me. Their bodies are still growing, why do that?