A long time ago I saw some talk show while flipping channels where the girls wanted to get pregnant. If I remember correctly, at least one of the girls was 13 or 14. It was one of those things where they bring the parents and the kid on, and the kid just keeps saying that she'll keep having sex and tearing the condom or whatever (no matter what her parents try to do). I guess talk shows aren't that much to be believed, but it wasn't something completely off the wall like Jerry Springer.
As for 30 year olds, I don't know how old the boyfriends of those girls were. I got the impression that maybe 17-19 was the age, but I've met plenty of girls that all had encounters (of their own choice) with guys that were in their late-20's while they were 14-16. Of course, I'm hearing this once they are older so I dunno.
Both of these situations are basically young girls trying to do adult things to somehow prove that they are mature and grown up. I just assumed that there is probably some cross-over between the group of girls that want to date guys twice their age to seem more mature, and girls that want to become mothers to prove their adulthood.