West broke the news Sunday night during a concert in Atlantic City. West told concertgoers to congratulate his "baby mom" and that this was the "most amazing thing." ( since the home porn tape)
"KIMYE!," tweeted sister Khloe Kardashian Odom. "Keeping secrets is hard with so many family members! Especially when you are so freaking excited!!!!! LOVE is everything!!!," she added.
"Been wanting to shout from the rooftops with joy and now I can! Another angel to welcome to our family. Overwhelmed with excitement!," tweeted Kardashian's other sister, Kourtney Kardashian, who has two children of her own.
Kardashian's mother, Kris Jenner, expressed her excitement on Twitter, tweeting, "Oh BABY BABY BABY!!"
Congratulatory tweets are already pouring in for the future parents.
"Congrats to Kim and Kanye. Happy for both of them," Russell Simmons tweeted.
Kardashian filed for divorce from NBA star Kris Humphries in October 2011 after 72 days of marriage.