The tears, the tension, the uncertainty, the drama...if anyone can look at that and say "I wanna be just like that", then they probably were going to end up in a similar position with or without the show.
If parents were smart and/or simply proactive, they would be sitting there with their children discussing what they're watching. If you want to keep a kid from doing something, answer every single question they are brave enough to ask you when it comes to sex and relationships. Says the woman with no children...ha!
But anyway, I feel like if I had a show like Teen Mom when I was a teenager, things might have played out a little bit differently for me.