The actress previously revealed she may name the child after a character in the soap - and it appears she went for battleaxe Hilda Ogden, played by Jean Alexander from 1964-1987.
McAlpine, who plays Fiz Stape in Corrie, already has a son, Albert, with husband Chris Farr.
The 34-year-old revealed she had given birth in a tweet.
She said: "Our newest addition arrived yesterday. Mummy and Daddy very happy. Big brother very proud of his little sister Hilda. We're all in love."
McAlpine has played the role of Fiz in Coronation Street since 2001.
She also took part in season 17 of I'm a Celebrity... Get Me Out of Here! in 2017, where she came in fourth place.