My work mates all knew I was pregnant before I reached 9 weeks because I looked big and couldn't fit into my clothes. I bought some flowing blouses to hide it before I reached 8 weeks. I looked "chubby" rather than pregnant, so if you didn't know me you wouldn't have guessed that the extra weight was baby. In fact, I basically just looked chubby until 25 weeks when the bump really started to look more like "baby" than "fatty."