Leave it to Alec Baldwin to nearly spoil Elizabeth Banks' surprise.
Before the actress, 38, and husband Max Handelman, 39, announced the birth of their son Felix via gestational carrier in March 2011, Banks' 30 Rock costar, 54, sensed something was up.
"Alec Baldwin asked me straight up," Banks tells the June issue of Allure. "I had made a comment about wearing a fake belly, something innocuous, and he looked me straight in the eye and asked me, 'Are you pregnant right now?' And I blanched totally. Because of course, technically, no I wasn't. But then, technically, yes, in a way I was! And it was very weird."
"I thought Alec was reading my mind or something," the actress adds. "We weren't telling anyone then, so I said 'No.' I thought, 'Is that a lie?' Because it wasn't a lie, and yet it was a lie!"
Of her son Felix, Banks explains: "It's essentially a test tube baby -- it's just the test tube is another woman. That you can grow a baby outside of yourself! It's amazing!"
"I did [the movie] for my fellow females," says Banks, who stars alongside Jennifer Lopez, 42, Cameron Diaz, 39, Anna Kendrick, 26, and Brooklyn Decker, 25. "I thought I was standing up for all the women who have crazy horrible pregnancies -- you know, there's all these things we're not allowed to talk about in public."
In her Allure interview, Banks also opens up about her weight -- sort of. "It's not good to put in a magazine what I weigh because it's too little. People freak out when they hear what I weigh," Banks says. "They think, 'Oh, you're too skinny.' But I ate a cupcake last night -- and I eat broccoli. I work out with a trainer; she kicks my ass."