Kim Kardashian has said she and Kanye West are feeling "so blessed" to be expecting their first child together.
Writing on her blog, the reality TV star said: "It’s true!! Kanye 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."
Kardashian's father, Robert, died in 2003, while West's mother, Donda, died in 2007.
The 32-year-old added in the post that she was "looking forward to great new beginnings in 2013 and to starting a family".
West, 35, revealed to a crowd of more than 5,000 fans during his concert on Sunday that his girlfriend was pregnant.
He told concertgoers to congratulate his "baby mom" and that this was the "most amazing thing".
Kardashian was in the crowd at Revel Resort's Ovation Hall with her mother, Kris Jenner, and West's mentor and best friend Jay-Z, whose wife Beyonce had a baby girl a year ago.
The pregnancy news instantly went viral online, with thousands posting and commenting on the expecting couple.
Most of the Kardashian clan tweeted about the news, including Kim's sisters.
Kourtney Kardashian wrote: "Been wanting to shout from the rooftops with joy and now I can! Another angel to welcome to our family. Overwhelmed with excitement!"
Another sister, Khloe, wrote: "I'm excited for Kanye and my sister! There's nothing like bringing life into this world! Let's keep Gods blessings coming!"
Messages of congratulations also came from Kardashian's younger sisters Kendall and Kyle Jenner, who tweeted "Whos excited about the KIMYE babbyyy?!" and "Congrats to this beautiful couple. I love you guys".
Her mother Kris Jenner also tweeted, writing: "Oh BABY BABY BABY!!"
Kim and her family star in the television reality show Keeping Up With The Kardashians, as well as a number of spin off series.
The rapper and reality TV star went public with their relationship in March.
Kardashian married NBA player Kris Humphries in August 2011, but separated just two months after their lavish wedding.
It was aired on US television channel E! as a two-part special with magazines paying for exclusive pictures.