Angelina: Breast Feeding Twins Is 'Very Hard'
11/18/2008 AT 04:30 PM EST
"It's very hard," the actress confessed on Britain's morning show GMTV. "I stopped at three months, [it was] about as much as I could do."
The actress, 33, who was in London promoting her film The Changeling with her partner Brad Pitt in tow and their four-month-old twins, Knox Léon and Vivienne Marcheline, said she even resorted to manuals on the subject.
"There's this football hold – it's a lot harder than it looks in the books,” she says in the prerecorded interview at her London hotel on Monday. "I did that a few times. I would take turns. It just takes a long time."
The mom of six also revealed that it was while filming The Changeling that she became pregnant with the twins: "We decided to start trying in the beginning, and by the end I was."
In the film, Jolie plays a mother whose son goes missing, based on a true story.
On whether marriage is important, Jolie says categorically "it's not" – explaining, "we jumped into being a family first. And that just seems like the biggest commitment you can possibly make. It doesn't feel like anything's lacking."
Who's your Favorite Star Under 35? PEOPLE.com and the People's Choice Awards are counting your votes! Click here to vote now!
Brad & Angie welcome Vivienne & Knox