Since I refuse to go on international boards and I value the opinion of you ladies x1,000 I am just going to ask here:
I just found out a bridesmaid is pregnant. Let it be known that I am incredibly happy for her and this isn't one of those "I need a replacement BM" posts. My issue lies in the fact that we just ordered bridesmaid dresses last week (pregnancy wasn't expected- she isn't married and this is #3). I felt like a huge b!*ch for ordering my bridesmaids to go buy their dresses last week (they went on sale and ran out of smaller sizes online). Now I am at a loss for what to do. These were from BCBG so not exactly maternity appropriate.
So my ? is: Do I have her be the only bridesmaid in a different dress (whether color and/or style) or do I change the dress that everyone wears?
For reference, here is the dress my BMs are wearing:

TIA!
ETA: BM will be about 22-23 weeks along at time of wedding.