Should I Alter My Bra Size? ?

If the bra isn't hugging the rib cage then perhaps you need to move up a band size in addition to cup size. Or the bra could be a bit stretched from wearing. It might be time to be measured and try a few different bra style to see if there's something new and perhaps a bit better out there for you. The bulging is a warning that the size your wearing isn't quite right for you. In any case try to find a good boutique or department store that does measuring and fitting and try on a whole bunch of bras until you find one that you like, then buy a bunch of what you like best.