(NEW YORK) -- Mariah Carey's birthday was more eventful than she likely expected.
Carey, who turned 41 on Sunday, tweeted that she began having contractions Saturday night and went to the hospital. She continued, "Finally they said I could come home after they got it under control but they almost came on 3/27- happy anniversary in deed [sic]!!! We have a few more weeks 2 go but- wow!!! :)"
Carey famously refers to her birthdays as "anniversaries." She and husband Nick Cannon are expecting twins.
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