I would suggest talking to nurses in hospitals in your area, who work in the specialties which you mentioned.
I am an OB nurse with 20 years experience; I've been an RN for 23 years. I have never worked pediatrics, and never want to! I know that everyone has their preference, and a great many ped's nurses do not want to work with adults.
At this time, I work in one of those hospitals with a womens & childrens service department. I am currently being told that "everyone" (all the RN's & LPN's in our unit) "will have to become comfortable with pediatric patients." However, there is no pediatric orientation program in place, and we don't see all that many ped's patients to begin with.
INVESTIGATE the possibilities, and be sure to find out what any hospital unit's new employee orientation policies & programs are like!
Katie C. in Pensacola, FL