Kanye, looking out at more than 5,000 concertgoers, said, "Stop the music and make noise for my baby mama … now you having my baby!" Kim -- who was at the concert -- is 12 weeks pregnant and reportedly did not know her hip hop beau was going to make the news public that night.
Kardashian took to her official site Monday to post the following: "It's true!! Kanye (West) and I are expecting a baby. We feel so blessed and lucky and wish that in addition to both of our families, his mom and my dad could be here to celebrate this special time with us. Looking forward to great new beginnings in 2013 and to starting a family. Happy New Year!!! Xo"
The announcement caused an uproar of celebration from fans on Twitter and Facebook, including delighted reactions from Kim's mother and sisters.
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Kourtney, who has two young children, Mason and Penelope, tweeted: "Been wanting to shout from the rooftops with joy and now I can! Another angel to welcome to our family. Overwhelmed with excitement!"