The actress, 35, who formerly starred on The Sopranos, and her musician boyfriend Shooter Jennings, 28, welcomed their daughter Wednesday night, reps for the actress confirmed to E! Online.
Alabama is the first child for Drea de Matteo and Shooter Jennings, who have dated for six years.
De Matteo, who played Adriana La Cerva on the HBO drama and also starred in the ill-fated NBC sitcom Joey, announced the pregnancy in May.
In June, even before she knew the gender, Drea de Matteo had a feeling she was having a girl. "I use 'she,' because I'm getting so fat, I think it's a girl!" she said at the time.
Shooter Jennings is the son of the late country legend Waylon Jennings.
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