I went from A to DD during pg, up to E after the birth for a few weeks and then back to D till I stopped bf'ing, went down to B afterwards. I'm 23 weeks in 3rd pg and a D at the moment. Anybody's guess really.
Do you know about bra extenders? They help with your ribcage expanding if not with the cup-size!
After feeding my DS for 16 months and having loads of bras. They still went south. I stopped wearing bra's about 6 months ago and I have not noticed any futher slackness but I have notice that my back feels loads better. I am going to leave it as long as I can before buying a feeding bra. I tend to wear camisoles with lycra to keep them in check lol
After buying replacements every few weeks I've decided to go for the ones that just come in small, medium, large etc. Hoping they'll keep me going for a bit longer. They're ugly as hell but I'm so fed up of being uncomfy. They have some on the NCT website if anyone's interested.
If it's any consolation Tyaca, I'm 38 and a bit weeks and I'd say most of my growing happened in the first trimester. It's settled right down now. I've just ordered nursing bras in the next size up for when the baby comes but I've got no idea what to expect in terms of how big they'll get or how they'll look once I've stopped breast feeding. I dread to think
PS. I just got some (new) bras on eBay for a fraction of what they cost in the shops. I'd recommend getting cheap things on ebay or in sales rather than forking out for bras which you'll outgrow in a few weeks/months.