I hate to sound like a broken record (I've posted this on several threads), but I had *awful* problems with every form of hormonal b.c. I tried (extreme depression, anger, physical effects like what FreeDuck mentioned, chronic bladder infections...) . I didn't want to give up on them because of the convenience, but I was so miserable I finally had to. Took a long time to realize what the problem was because doctors tend to take the "Oh, no, you're not at risk for the common side effects" line, and are either not very aware of -- or are not very forthcoming about -- the frequency of other side effects, IMO.
Anyway, we've switched to condoms and are quite happy with that. They have a low failure rate as long as you really do use them absolutely correctly. And Mr C will probably go the vasectomy route when he's older, as an even better alternative (I'm
awfully glad I'm not with one of those guys that freak out at the mere suggestion of that possibility!).
I'm not saying not to try the Pill, but just for her to be really aware of how she feels when she's on it. (My husband just chimed in, "If you want her to turn into Satan, go for it!"

I'm gonna go slap him...)