Yeezy announced the happy news while on stage in Atlantic City on Sunday night.
According to the Daily Mail, the rapper said, "Stop the music," before saying: "Make noise for my baby mama right here."
And the Mail reports that Kim's rep has confirmed the news.
After the big announcement, the excited Kardashian clan took to Twitter to congratulate the couple.
Kourtney wrote: "Been wanting to shout from the rooftops with joy and now I can! Another angel to welcome to our family. Overwhelmed with excitement!"
Khloe couldn't contain her excitement either, tweeting: "KIMYE!!!!! Keeping secrets is hard with so many family members! Especially when you are so freaking excited!!!! LOVE is everything!!!!"
Meanwhile grandmother-to-be Kris Jenner simply wrote: "I'm a happy girl !!!!!!!!! Wowza!"
Kim and Kanye have been a couple since April but have been friends for years - which the curvy reality star claims is the reason they have such a good relationship.
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