Splash News 1 / 8

Katherine Heigl is going on hiatus from "Grey's Anatomy," a rep for ABC confirms to Usmagazine.com.

Entertainment Weekly, which first reported the story, says Heigl will take a five-episode break from the medical drama to film romantic comedy "Life As We Know It" alongside Josh Duhamel.

"The exact schedule is still in the works," a source tells Us.

Heigl, who plays Izzie Stevens, has already shot six episodes this season, and will appear on-air through November, the source continues.

A source says Heigl's absence will likely coincide with Ellen Pompeo's maternity leave (she's due in October with her first child). Patrick Dempsey may leave the show temporarily to shoot a movie.

"These plans have been in the works for a while. The producers, as they always have, do their best to accommodate people's schedules, including Katherine's movie schedule, a film schedule for Patrick, and Ellen's maternity leave," the insider says. "Ellen will have as much time as she needs and wants as a new mom, and the chances of her leave overlapping with Katherine's is highly likely."

Continues the source: "This is how Grey's works: It's a true ensemble. The show will be firing on all cylinders while at the same time accommodating the actors' needs."

Heigl's absence "will of course be explained through the storyline," the insider adds. On last season's finale, Izzie appeared to die from a brain tumor, and Us Weekly first reported show creators were considering killing her off permanently. E! reports she'll be fired from Seattle Grace hospital when it merges with Mercy West hospital.

"Eventually, everybody is going to leave the show," Grey's creator Shonda Rhimes said earlier this year. "So we're looking at [ways] we can mess with the structure now.... Season 6 is about finding the longevity of the show and figuring out if there is a future for this show beyond these characters."

T.R. Knight announced his departure from the show in July, calling it the "best decision" he could have made.

Actors Nora Zehetner, Robert Baker, and Jesse Williams will also be joining the cast this season, which returns Sept. 24.

More on Wonderwall:

See which stars think they're too-cool-for-school

What car do you think Katherine Heigl drives?

Become a fan of WW on Facebook

More on Usmagazine.com:

See photos of romantic comedy stars now and then

Check out photos of TV's hottest doctors

Check out the love lives' of Greys stars