I have been on the Nuva Ring for a few years now, but Trileptal interacts with it, meaning I essentially have to use another form of bc since it decreases its effectiveness. The only reason I'm on the bc is to keep me regular (since I've never really been regular) and because the Trileptal was causing breakthrough bleeding when I started taking it.
Anyway, I've noticed the past two months that the week it's out that my moods are super crazy and I get really depressed. Which is weird because it's rarely effected me before. So I'm inclined to say hormones do in fact effects bipolar, but I don't think it is the cause of it. (my thyroid has been checked in the past too, it's always been on the normal side of normal, but its still in the normal range, so it's left as is)