Credit: Denise Truscello/Getty Images for Cosmopolitan Magazine

Mario Lopez is a first-time dad!

The Extra host, 36, and his girlfriend, Courtney Mazza, welcomed a baby girl, Gia Francesca Lopez, Saturday in Burbank, Calif. Gia weighed in at 6 lbs, 4 oz.

"We are so overjoyed. What an amazing, wonderful and overwhelming experience to welcome our daughter into the world," Lopez told Extra after his little girl was born.

Lopez and Mazza, 28, who met while costarring in Broadway's A Chorus Line, waited until delivery day to learn their baby's sex.

"Where else in life do you get such special surprises?" Lopez, who penned a book for first-time dads due out next year, asks. "I hope with all our kids it will be a surprise."

As the new parents ready their daughter's nursery in their Glendale, Calif., home, Lopez tells Us he wants more children.

"As many as she'll give me," he says. "At least three!"

For an exclusive sneak peek at baby Gia's nursery -- which Mazza says was inspired by Jennifer Lopez -- pick up the new issue of Us Weekly, on newsstands now.