Motherhood Maternity sometimes carries upto size H, other then that I just have to get a bigger band and go with one from wally world (I have to get a 44-46 band and a DDD cup to get it to work). There is a local store here that does custom fittings and has up to cup size K and band size 52 or 54 but I dont think you're willing to drive 8 hrs just to get a nursing bra
But also once the engorgement period is over and your supply "stablizes" around 4ish months then its easier cause your boobies aren't all hard and such, and when her head starts getting bigger its a little easier(Kieran's head is still smaller then me though

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