I am 18 weeks pregnant with my second baby and could tell by my clothes and general feel of my bum that it was growing. Tonight as I was getting into the bath I made the horrifying mistake of looking at it in the mirror. 
I did not recognise my own bum! It looked more like my Mum's bum which even as a child I knew was not the finest specimen.
This did not occur with DD1. I am scared it will never return to its former glory. Please reassure me that all is not lost.