I think youve just answered your own question.
I run a clothing company and we work damn hard to provide accurate measurements of our pieces so that customers wont be disappointed when they get them- I imagine Baby' does the same. If you see the measurements on the Baby site and compare them to your own you will know how the clothing will fit. If you dont squeeze into their measurements then its not the brand for you. *shrug*
Best be informed and really consider an online purchase prior to making one.