Fox Thought She Had 'Vampire Baby'

Fox Thought She Had 'Vampire Baby' (ABC News)

Kicking butt on movie sets might have made Megan Fox famous, but it didn't prepare her for the battleground of the delivery room.

The "Transformers" and "This Is 40? actress opened up to Jay Leno on "The Tonight Show" Monday night about giving birth to her son, Noah Shannon Green, in September.

"I thought I was going to be tough and the nurses would be like, 'She's a warrior princess. She doesn't need an epidural. She's amazing. We're such big fans.'" Fox said. "As soon as I got out of the car, I was already crying for an epidural. I was asking the security guard for an epidural."

Fox said that while most of her pregnancy was perfect, her first trimester was filled with horrible morning sickness and - yikes! - the fear that the creature growing inside her might not even be human.

"It was so bad for me actually that … I was convinced that I was maybe birthing a vampire baby," she said. "Like the one from 'Twilight' you know what happens to Bella, where she's in cold sweats all the time. I felt like that was happening because I had no vitamins and nutrients I was just nauseous."

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Fox also experienced "pregnancy brain" which she said, is a "very, very real thing."

"I had it so bad that Brian [Austin Green, her husband] wouldn't let me drive anymore," Fox said. "I would do things with my cell phone like I would go to get the juice out of the refrigerator and I would leave my phone … or I would be walking around the house yelling, 'Where's my phone?' and it would be in my hand."

Though she co-stars in Judd Apatow's latest comedy about middle age, "This Is 40," the 26-year-old new mom isn't ready to get older just yet.

"It sounds so old to me," she said about the big 4-0. "I try not to think about it."

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