For example, it's the liberal parent syndrome. You know, the type of parents who are of the mindset that you shouldn't say anything negative about sex, that their children will figure it our on their own, or do what's best for them, and that they'll support them if they need birth control, albeit an abortion or whatnot.
I have seen this type of parent. They're the ones who will ask their daughter if she'd like to go on the pill, if she needs condoms, or if she is sexually active, while exclaiming to her that if she gets pregnant that she can go on down to the clinic and get an abortion (aka MURDER her child).
This type of parenting is devastating for any child, and it actually PROMOTES sexual activity, for it is seen as a condonation of sex in the first place. For example, "mom has asked me if I've had sex. She's asked me if I need birth control pills. She's asked me if I need condoms. She's stated that if I get pregnant, all I have to do is get an abortion". This is the mindset.
While teaching your child about the dangers of premarital sex and abstinence is not 100% fool-proof, the success of these methods are lightyears ahead of liberal "sex education" advice and parenting. Teaching middle and high school kids how to put a condom on a banana actually promotes sexual activity. Secondly, passing them out says to the kids, "see, our role models say it's okay to have premarital sex".
When parents, as well as society, embraces abstinence education, the rewards and successes are much more common. Like I said, it is not one hundred percent fool proof, but it has far better results. Of those with a great, abstinence up-bringing, nearly all do not have sex as teens. Those that do lose their virginity are much older, say in their early to mid 20s, and many of them by that time are in good relationships that will secure them a partner for life. Now, I'm not saying that this applies to everyone, but rather a general trend that has lots of validity.