I guess most of the people above have answered the OP's question.
Actually AA has advised me the same thing. Here was my experience:
I flied from Sydney to Houston last December. Initially I planned to fly CX to HK then PVG, then AA from PVG to Chicago then Houston... lucky I called AA and they have advised me I have to recheck everything at PVG if I wanna go that way...
I end up with CX from Sydney to HK, then Narita, then Dallas then Houston... luggage went through all the way to Dallas (need to recheck there) from Sydney.