Jennifer Aniston "wants to be pregnant as soon as possible."

The 43-year-old Hollywood star and actor Justin Theroux have been in a committed relationship for nearly a year.

Jennifer desires to establish a family with Justin very soon.

"Ideally, she wants to be pregnant as soon as possible, but if it doesn't happen by next year, they're going to adopt," a source told OK! magazine.

"Jen has always been very open to the idea. Plus, it seems these days so many people in her circle are opting to do it that it's got her thinking of it more and more."

Jennifer feels her biological clock ticking.

"The fact is, she wants to have more than one child and now that she's in her 40s that's becoming less likely," the source explained. "She wants her baby to have at least one sibling."

Jennifer is also interested in building a business enterprise with Justin.

She and her ex-husband Brad Pitt owned production company Plan B together, but Brad became the sole owner of the venture following their 2005 divorce.

Jennifer laments that decision.

"She's planning to set up a production company with [Justin]," the insider revealed. "Giving up [Plan B] was something she always regretted. But with Justin, she feels she has a second chance. He has a number of scripts written, and Jen's really pushing to get them made because she's a huge fan of his work."