There are so many things that could happen that we can't predict or control that might raise others suspicions. However, I'd like to think that most people are smart enough not to ask about someone's pregnancy without knowing for sure. If they do have the balls to come right out and ask - then just DENY! DENY! DENY!
LOL! Well most people are smart enough, but I seem to know some that don't mind asking. I have had two coworkers ask me since I've been pg when I was going to have a baby. It's like they have a sixth sense or something.
Also, a while back, my MIL felt the need to check with me to make sure she would not find out we were expecting via Facebook. Like, obviously I am not going to tell you that way! She said she wants to find out in a creative way. No pressure or anything!