Jennifer Aniston Pregnant - with Twins?

Jennifer Aniston's reps have already denied that she's pregnant, but Star Magazine is still running with their story.

A few weeks back the magazine claimed that Jenn was pregnant with John Mayer's kid, and now they're claiming she's having twins!

Apparently Jenn has been undergoing fertility treatments in a bid to get pregnant before her 40th birthday. "She knows her baby-making years are limited," says a source. "It's hard for her to think of anything else — she has babies on the brain!"

It gets better! Apparently John, who is an infamous womanizer, is really excited about the thought of being a dad and has started buying up pregnancy and parenting books.

We want to know who this "source" is. Do they live with John or Jenn? It sounds a little absurd to us, but than again Star magazine has surprised us in the past. What are your thoughts?

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