Tina Fey and Amy Poehler arrive to the "Baby Mama" premiere at the Ziegfeld Theatre, during the 2008 Tribeca Film Festival on April 23, 2008 in New York City.
Dimitrios Kambouris/WireImage.com

CelebNews@Usmagazine.com! - Baby Mama Tops Weekend Box Office

Oh, baby!

Tina Fey's comedy Baby Mama delivered big bucks at this weekend's box office.

It was the No. 1 film, grossing an estimated $18.3 million.

Baby Mama – about motherhood and the maternal urge — had the second-best opening for a romantic comedy in April (Jennifer Garner's 13 Going on 30 still takes the title), according to Variety.

What contributed to its box office success? Fey and co-star Amy Poehler.

"I think Tina Fey and Amy Poehler were the big draw," Nikki Rocco, Universal's president of distribution, told Variety. "You are going to be entertained."

The weekend's other highly anticipated comedy, Harold & Kumar Escape From Guantanamo Bay, came in at No. 2, with an estimated $14.6 million.

Michelle Williams' return to the big screen — the erotic thriller, Deception — tanked, earning just $2.2 million and securing the No. 10 spot.

The complete top 5:

1. Baby Mama: $18.3 million
2. Harold & Kumar Escape from Guantanamo Bay: $14.6 million
3. The Forbidden Kingdom: $11.2 million
4. Forgetting Sarah Marshall: $11 million
5. Nim's Island: $4.5 million

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