Katherine Heigl Explains Why Anne Hathaway Turned Down Knocked Up Role

Anne Hathaway turned down the lead role in "Knocked Up" because it was "too radical," Katherine Heigl says.

The 30-year-old "Grey's Anatomy" star, who landed the role of Alison Scott in the hit romantic comedy, reveals Hathaway was the first choice for the part but she declined the role.

She says, "I think Anne found the film a little too radical especially with the shot at the end!"

That "shot" actually delighted Heigl because it made the men screamed. It was a graphic footage of a baby's head while it was being pushed out of her body during the birthing scene.

Heigl says, "Seeing a baby's head poking through was a little strong but the reaction of the audience at that point was extreme. They just screamed - especially the men!"

"Knocked Up" tells the story of Alison and Ben Stone, played by Seth Rogen, who have little in common with each other yet faces the dilemma of unplanned pregnancy after a one-night stand. The film opened at number 2 and grossed $148.8 domestically as of December 30.