That is to say, "Just don't fornicate."
Hell, you can fornicate if you want.
Simple be prepared to deal with the consequences.
In biblical times, this was handled by marrying daughters off at a young age. Like 13.
In a time when people don't tend to marry until late 20's or early 30's, asking guys to stay celibate until marriage is not going to fly.
Personally, I would like to try to fix the problem, by encouraging girls to find their husband while young.