Beyonce' & Jay-Z: It's a Girl!

According to TMZ:

Beyonce finally popped, giving birth to a baby girl named Ivy Blue Carter in New York City on Saturday

Proud dad Jay-Z, real name Shawn Carter, was at the hospital where Beyonce reportedly birthed Ivy by c-section -- and shortly after her arrival ... J & B's famous friends started sending out birth announcements on the Internet.

Rihanna tweeted, "Welcome to the world princess Carter! Love Aunty Rih"

Hip-hop mogul Russell Simmons also took to Twitter, saying ... "congrats to my good friends Beyonce and Jay-Z."

Beyonce famously announced her pregnancy on stage at the MTV Video Music Awards back in August.

According to other sources:

Beyonce and Jay-Z, rented out the hospital’s entire fourth floor for $1.3 million, the employee said.

In an effort to keep images from leaking to the public, hospital workers placed tape over security cameras and are forcing employees to turn in cell phones when they arrive for their shifts, the source said.

Several security guards were spotted patrolling the outside of the hospital Saturday night. A Lenox Hill staffer confirmed that a patient named Ingrid Jackson was in a “labor room.”

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