Beyonce and Jay-Z

Beyoncé and Jay-Z welcomed a daughter Saturday in New York, the couple confirms in a statement obtained by E! Online.

"Hello Hello Baby Blue! We are happy to announce the arrival of our beautiful daughter, Blue Ivy Carter, born on Saturday, January 7, 2012," the 30-year-old singer and 42-year-old rapper said in a joint statement Monday. "Her birth was emotional and extremely peaceful, we are in heaven."

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The couple dispelled earlier reports that baby was born via a scheduled C-section. "She was delivered naturally at a healthy 7 lbs and it was the best experience of both of our lives. We are thankful to everyone for all your prayers, well wishes, love and support."

The couple's famous friends were already tweeting their congrats late Saturday and early Sunday. "Welcome to the world princess Carter! Love Aunty Rih," Rihanna tweeted late Saturday. "Welcome to the world Blue! We love you already," Gwyneth Paltrow wrote early Sunday.

Blue Ivy Carter's arrival comes a week after several media outlets reported that the former Destiny's Child lead singer had already given birth.

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Originally due to give birth in February, Beyoncé checked into Lennox Hill Hospital on Friday under the alias "Ingrid Jackson," according to the New York Daily News. The couple rented an entire floor of the hospital — reportedly to the tune of $1.3 million — and security cameras were taped over to ensure the couple's privacy.

Beyoncé announced her pregnancy in late August at the MTV Video Music Awards, when she revealed her growing belly during a performance. She and Jay-Z, who have collaborated on hit singles such as "03 Bonnie & Clyde" and "Crazy In Love," married in April 2008 after dating for about six years. This is the first child for both.