EXCLUSIVE PHOTOS – Is Jennifer Aniston Hiding A Baby Bump?

Is Jen trying to hide something?

We spotted the Horrible Bosses star carefully covering her midsection as she waited for her car at the medical building in Los Angeles, on Tuesday.

Aniston has been paying frequent visits to an acupuncturist and to an orthopedist for her ongoing knee problems, but she's still wearing those high heels, of course!

The normally ultra-fit star has appeared to be a few pounds heavier, as of late -- sparking reports she's expecting her first child with beau, Justin Theroux. But Jen says it isn't so!

The former Friends star recently confessed to Britain's Hello! magazine: "No we’re not pregnant. It’s just I quit smoking, so I’ve gained a couple of pounds."

The 42-year-old star also took some time to clear up that "marriage" rumor, revealing:

"I am not planning to get married any time soon. This ring that I’m wearing is not an engagement ring. I’ve been married once and I don’t know if I’ll get married again, but I can tell you that as of this very moment, as of today, I have no plan to get married. Got that?"

We got it!

But that doesn't mean there couldn't be a baby in the very near future!