The 36-year-old actress – who gave birth to daughter Aviana in May – realised she was expecting when she was thirsty for her partner Darren Le Gallo’s favourite drink one day.
She explained: “I saw almond milk in the fridge - Darren drinks it, but I'd never tasted it - and it triggered an animal response. I was like, 'I need that,' and I drank the entire carton in 10 minutes. I looked at Darren and said, 'I think ... yeah, I'm pregnant.' "
The ‘Fighter’ actress also admitted giving birth made her more confident with her appearance and insists she no longer puts pressure on herself to stay slim.
She told Parade magazine: "Being pregnant finally helped me understand what my true relationship was with my body - meaning that it wasn't put on this earth to look good in a swimsuit.
"I was like, 'Look, I can carry a baby! I'm gaining weight right, everything's going well.' And I've had that relationship ever since.
“I've been working out when I can, and I'm trying to eat in a healthful way, but losing weight is not my number one priority. It's part of my job to return to some semblance of what I was before. But I don't feel I've ever made my career on my rockin' bod’."
Though Amy had no problems during her pregnancy, she was anxious throughout her entire term because she was aware of what could go wrong after playing an expectant mother whose baby is stillborn in 2005 movie ‘Junebug’.
The screen beauty – who was nominated for the Best Supporting Actress Oscar for her performance - admitted: "Because of how that film ended a lot of women have talked to me about their own similar experiences and how much that character touched them.
“Having played somebody who went through that, I was terrified."