The 'Empire State Of Mind' star made the surprise announcement via Instagram overnight on the same day she marked her wedding anniversary to husband Swizz Beatz.
Alicia showed off her blossoming baby bump in a sweet picture of herself and producer Swizz.
She added the caption: "Happy Anniversary to the love of my life@therealswizzz !! And to make it even sweeter we've been blessed with another angel on the way!! You make me happier than I have ever known! Here's to many, many more years of the best parts of life."
Swizz said on his own account: "Love is life and life is love and we're so excited for another GIFT from up above. Happy Anniversary my Goddess. Four years of greatness and cheers to 100 plus more inshallah."
Alicia, 33, and Swizz, 35, married at a private home on the Mediterranean Sea in 2010 following a two-year relationship.
They welcomed their first child, son Egypt, the same year.
Following his birth, proud dad Swizz told People that Alicia was a "natural mum" and settling into motherhood perfectly. "She even surprised my mum," he said, "who wanted to give her tips but was like, 'What tips can I give her?! She's already ahead of the game!'"
Congrats to Alicia and Swizz!
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