While restricting certain things can make it enticing to some people, most people will avoid it because of the ramifications or punishments that may ensue, or they just straight up know it's wrong. If Adam and Eve had really known what would happen when they ate the forbidden fruit they probably wouldn't have done it.

Restricting abortion for example will reduce abortion numbers because most women or girls will find it too hard to get one, too expensive to travel to another state, or maybe knowing that it's illegal will make them realize it's wrong and they'll actually choose life.

Restricting sex between teenagers or any unmarried people was never a law in the past, but it was extremely taboo and frowned upon, and in fact you would be shamed for it. That sort of ostracizing kept the majority of people from committing that act, and that's what we need again today.