Kim Kardashian pregnant with Kanye West's baby

This Oct. 22, 2012 photo released by Starpix shows rapper Kanye West, left, with his girlfriend Kim Kardashian at Gabrielle's Angel Foundation 2012 Angel Ball cancer research benefit at Cipriani Wall Street in New York. (AP)

Kanye West, left, and Kim Kardashian, right, as kids. (Snakkle.com)

Kanye West and Kim Kardashian (X17 Online)

A kid for Kimye: Kanye West and Kim Kardashian are expecting their first child.

The rapper announced at a concert Sunday night that his girlfriend is pregnant. He told the crowd of more than 5,000 at Revel Resort's Ovation Hall in song form: "Now you having my baby."

The crowd roared.

On Monday, Kardashian, 32, confirmed the news in a blog post on her website.

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"It’s true!! Kanye and I are expecting a baby," she wrote. "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."

The Kardashian clan chimed in, tweeting to share their excitement about the news. Kourtney Kardashian wrote: "Another angel to welcome to our family. Overwhelmed with excitement!"

West also told concertgoers to congratulate his "baby mom" and that this was the "most amazing thing."

The rapper, 35, and reality TV star went public in March. Kardashian is about 12 weeks along, according to TMZ.

Kardashian is technically still married to NBA player Kris Humphries. The two wed in August 2011 but split after just 72 days. Their divorce is not finalized.

The Associated Press contributed to this report. 

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