Miller, 30, who gave birth to her first child with fiance Tom Sturridge in July, was exhausted in the weeks after she first discovered she was expecting a baby, reported Contactmusic.
"I was pretty delirious. I was filming during the first trimester. It was actually quite distracting. The tiredness was quite debilitating. And you can sometimes use some of that in your acting," she said.
Miller planned to take a break after having her daughter, but changed her mind when she was offered a role in Bennett Miller's forthcoming film 'Foxcatcher', which was shot in Pittsburgh.
"Though I know I had promised myself not to work so soon after the birth, it was too good an opportunity to turn down. Marlowe has been on about 15 planes already," she added.
