The singer - who is expecting twins, a boy and a girl, with husband Nick Cannon in the next few weeks - adorned her huge bump with a picture of a butterfly, and admitted she is now ready to welcome her children into the world.
Writing on her twitter page, she said: "My attempt @ festiveness on 327! For ATLITL thank u + I U! Comin soon #dembabies! LYMA+thanx 4 making me happy:).(sic)"
However, Mariah explained she was expecting the twins to make their arrival on her birthday on Sunday (27.03.11) after she started to feel contractions, but she was later told by doctors it was just a false alarm.
She tweeted: "So #dembabies really wanted 2 celebrate w/us/share the anniversary! I started having contractions last night..went 2 the hospital-
"Finally they said I could come home after they got it under control but They almost came on 3/27- happy anniversary in deed!!! We have a few more weeks 2 go but- wow!!!: ) #soreadyallready!(sic)"
Meanwhile, actor-and-comedian Nick recently admitted he and Mariah are coming up with "unique" baby names for their new brood.
He said: "They won't be getting crazy names like Carburetor or something. But they're definitely unique."