Beyonce and Jay-Z on baby Blue Ivy: "We are in heaven"

NEW YORK, NY - SEPTEMBER 12: Recording artists Jay-Z and Beyonce watch Rafael Nadal of Spain and Novak Djokovic of Serbia play during the Men's Final on Day Fifteen of the 2011 US Open at the USTA Billie Jean King National Tennis Center on September 12, 2011 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Al Bello/Getty Images)
Al Bello
Jay-Z and Beyonce watch the Men's Final on Day Fifteen of the 2011 U.S. Open at on Sept. 12, 2011, in Queens, N.Y.

(CBS) Blue Ivy Carter's arrival was heralded on Twitter - and in a new song by her father - but now the baby girl's parents are making it official.

Proud parents Beyonce and Jay-Z confirmed news of their daughter's birth in a statement on Monday.

Pictures: Celebrity babies
Pictures: Beyonce

"Hello Hello Baby Blue!" the statement, posted on Jay-Z's website, begins. "We are happy to announce the arrival of our beautiful daughter, Blue Ivy Carter, born on Saturday, January 7, 2012. Her birth was emotional and extremely peaceful, we are in heaven. She was delivered naturally at a healthy 7 lbs and it was the best experience of both of our lives."

It continues, "We are thankful to everyone for all your prayers, well wishes, love and support. Beyonce & Jay-Z."

Earlier Monday, Jay-Z posted a song on his website called "Glory," which announced the birth of the couple's daughter. The track ends with the sound of a newborn crying.

In the song, he raps, "The most amazing feeling I feel / Words can't describe what I'm feeling for real / Baby, I paint the sky blue / My greatest creation was you."

Congratulations have also come in via Twitter from some of the couple's famous friends, including Gwyneth Paltrow, Rihanna, Russell Simmons and Beyonce's sister Solange Knowles.