Wow, this is such a good question.
Well any good, responsible and God fearing person will advise his child not to engage in pre- marital sex until he or she gets married.
A good parents will advise his child of the danger of premarital sex, alot of young folks have been infected with different sexual diseases due to premarital sex.
Though using condoms are always advisable to people but we are talking about parents and their relationship with their children and not doctors or medical advice which are two separate issues.
Medical advice is that you use condoms when having sex with someone you are not married to but no good parents will want their children doing such until they are married.