Thanks for your post, Yellow Lolly Ellie Horry - and that's a good point!
Have to say I fainted once on the London Tube when I was only a few weeks' pregnant and couldn't get a seat (too scared to ask). As I came round, people were stepping over me to get out at the next stop!
I can only assume that, as I didn't have a noticeable bump yet, they all thought I was drunk or something.
I went and got a Baby On Board badge the very next day!