I don't like the article because it seems to extrapolate quite a bit from a very small sample size. The researcher even says that you can't draw conclusions about most parents or teens and yet it seems that they turn around and do it anyway.
This is one area where I think having been a single teen parent gives me a bit of an advantage. For one thing, it wasn't THAT long ago that I was in that position. I sometimes think that parents forget, unintentionally, what it really was like when they were kids, and that is just a fact of time. The more time you are removed from something, the harder it is to remember the details.
In addition, when discussing with my teen daughter (she's 14) we have real life examples that she's lived to fall back on. I can say things like remember when we had to live with Grandma? We can discuss things from the point of view of what we had to do when she was a little kid and how we live now (I am married, having more kids, we own a house etc) and what she wants for the future and does she really want to have to make the choices we had to when she was little.
And, as I said, I am now having more kids. I have a 19 month old and am pg again. She was in the delivery room when the 19 month old was born and likely will be again. Watching me go through pg (and the present one has been pretty rough on me) and labor and delivery DOES have an impact on her. It also provides fantastic openings for discussions, as does the whole having a different biological father issue.
I know she's "interested" in sex. I can't imagine she wouldn't be, I was curious about it at 14. But I also know she doesn't have a boyfriend, and doesn't generally hang out with boys. She's just getting into high school and is trying out for the soccer team and as she gets more independant, I am sure the issue will come up for her. But, I remember when I was a teen, I didn't do drugs or drink because really, I simply didn't have easy access. I had sex because I had easy access. And, at the moment, she doesn't really have easy access to any of it. So, for now, I am not worried. But, I also remember that who I was at 14, vs who I was at 16 and 17, they were VERY different. I expect the same will be true for her.