Sarah Stage is a gorgeous, super fit 30-year-old model who happens to be eight-and-a-half months pregnant, not that it's easy to tell.

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Stage has become an Internet sensation over the course of her pregnancy, posting a slew of photos to Instagram chronicling her development. Her fan base has grown exponentially since she started documenting her pregnancy.

So how does a woman who is about to give birth seem to have no baby bump at all? Stage has managed to stay slender through a strict exercise regime and practices a healthy diet.

The Los Angeles-based fitness model doesn't keep herself from indulging occasionally. According to her Instagram posts, she treats herself with In-N-Out burger, but only occasionally.

Aside from her many pics in bikinis, lingerie and work-out gear, Stage has also bared it all, going fully nude to show off her tiny baby-bump.

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