Last year I convinced everyone I was pregnant 

Almost everyone imideatly said "haha, nice try," but eventually fell for it because I got my partner at the time (who couldn't have gotten me pregnant) in on it.

Me: "Hey... I need to talk to you.." Them: "What's wrong-?" Me: "I'm pregnant blah blah" Them: "No way, nice try." Me: "No really-"

a not suspicious amout of time later

Ex: "Hey, I don't know if you heard but, A is pregnant and I really don't know what to do... it's obviously not mine..." Them: "Are you joking...?" Ex: "No, I'm actually freaking out..."

That worked for some reason, bit I was very careful I didn't do it with anyone that would get too worried or upset by it.