to pose another possibility, to test before breast reduction. both my friend and i have experienced boob issues, pain and the like. She is a 32 HH in english sizing, which i think is about a 32 H in American? not really sure, a quick google told me that there are two sizing methods. anyway theyre big. myself, a 30 E or an american 30 DD i think.

Ive also found that for years we have been wearing the wrong shape and size bra. if theyre getting in the way and hurting your back i would recommend really questioning whether its the bra? the measurement around the band actually to most people is the actual measurement of their chest wall, none of this add four inches rubbish. also, if you go down a band size you need to go up a cup size. also you can be larger on top or larger on the bottom, affecting the fit of a bra. i vote measure your underbust/band size, go to the shop that does for large busts, pulling out all of them in your chest size in varying cups. pull out some bigger than your cup size and some in a smaller chest size. i remember the day i went from an english 32 DD to a 30 E. suddenly everything was amazing.

a brand i swear by, which is actually european is Freya. they do bras in much wider
sizes.

just something to think beforehand, because bras are cheaper than augmentation. if that doesn't work, it was worth a try.