Really, you would rather your kid have sex in a car then at home
Now, I am not talking about 12-15 year olds but if you know your 16-18 year old is having sex why would you want them to sneak around, have sex in cars and risk getting arrested, or not have the proper things to protect themselves? When I was in high school, most of the kids who had sex and didn't use both birth control and condoms didn't use them because they couldn't get them without their parents knowing. Yes, they could ge buy them but they were afraid their parents would find them. How stupid is that? My kids are 13,. 16 and 19 and my 16 year old DD has sex with her boyfriend in her room, my 19 year old son has had sex with 2 girlfriends in his room (different times, both long term relationships). Instead of making them feel like they have to sneak around, I teach them manners about it. Don't flaunt it (I don't want to hear screaming and moaning, just like they don't want to hear that from mine and their dad's room) and be as safe as you can be. My kids all know they can come and talk to me because they know that what they are feeling is natural and nothing to be ashamed of.
My son knows that even if a girl is actually on the pill as she says she is, it is easy to forget so he should always use a condom, and he does.
I understand that people parent differently but please understand that your refusal to deal with the fact that your kids may want to or are having sex will not stop them from having sex. But if you help them to protect themselves and have honest and open communication with them about it, you can stop them from having to deal with having sex too young, STDs and unwanted pregnancies.
Sorry, I just had a conversation with a mother of my DD's friend and the way she talked about teen sex blew my mind. She is one of those parents who thinks that if she doesn't talk to her child about having sex and protecting herself, she won't have sex. Meanwhile, this girl has been having sex with her boyfriend for over 6 months. I know because she talked to me about it. Of course I didn't tell the mom