The rapper announced at a concert Sunday night that his girlfriend is pregnant. He told the crowd of more than 5,000 at the Ovation Hall at the Revel Resort in song form: "Now you having my baby."
The crowd roared.
Kourtney Kardahsian and Kris Jenner also tweeted about baby news.
West also told concertgoers to congratulate his "baby mom" and that this was the "most amazing thing."
The Kardashian family confirmed the pregnancy to E! News.
The rapper and reality TV star went public in March. Kardashian married NBA player Kris Humphries in August 2011 and their divorce is not finalized.
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