It is well recognized that bra cup sizes vary from manufacture to manufacture. This perhaps contributes to the fact that many women do not wear the proper bras for their size. Yet all prospective breast augmentation patients know what size they would like to be and use the term “A”, “B”, “C”, etc as if their definition is written in stone. In reality chest size (the thoracic cage diameter) plays the most significant role relative to cup size and also breast implant size. For example: a 32 “B” does not have the same cup volume as a 38 “B”. This coupled with no manufacturing industry standardization makes for comparing cup sizes among girlfriends an exercise in emotional impressions if not futility. The size you should be is the size you like when looking in the mirror, rather than the misguided measurements of your friends. Once you choose a size tell your friends whatever they want to hear, otherwise you will be told by these “experts” that you chose the wrong size!