Does anybody know what the standard M&S or Blooming Marvellous formula is for calculating what size breastfeeding bra I'm going to need? And does this formula work? I hear it's something like take 2 inches off vastest pregancy size and add a "fistsworth" of cup size? I have to find this out in advance to do mail order as I live far from civilisation. I also seem to have a far bigger rib cage than most women, I started out a 40C pre pregnancy and now am 44C/D at 36 weeks. Thanks for any clues!