"I'm not planning anything. I can't imagine how big I'm going to get in the next three months, but ... you just kind of play it as it comes," Roberts tells Newsweek magazine. "I'm allowed to do that, aren't I?"
The Oscar-winning actress has two films set for release in December: "Closer," directed by Mike Nichols and also starring Jude Law, Natalie Portman and Clive Owen, and "Ocean's 12," the Steven Soderbergh-directed sequel to 2001's star-studded heist caper.
But very soon, pregnancy and children will take first priority.
Roberts tells Newsweek that her pregnancy has only just begun to show. "It does kind of happen overnight. You wake up and go, `Oh my God!"' said the 36-year-old actress, who is due to give birth this winter.
Roberts, who won the best-actress Oscar in 2001 for "Erin Brokovich," married cinematographer Daniel Moder in July 2002. The twins will be the first children for Roberts.
Of the somber "Closer," Roberts said: "I wouldn't think of me for this. And certainly, I wasn't Mike's first choice."
Nichols originally cast Cate Blanchett, but she had to drop out when she became pregnant.
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