Jessica Simpson: "Whenever My Water Breaks, It Will Be Like a Fire Hydrant!"

Though her extra large baby bump may indicate otherwise, Jessica Simpson still has about four weeks to go before she gives birth.

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Appearing on Jimmy Kimmel LIVE! Monday, the pregnant 31-year-old said she's growing tired of her pregnancy curves. "I feel I have a bowling ball sitting on my hookah!" Simpson laughed. "Apparently I have a lot of amniotic fluid, so whenever my water breaks it will be like a fire hydrant!"

Simpson isn't nervous about going into labor, though. "I'm ready to push!" she told host Jimmy Kimmel, 44.

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Though Simpson and fiance Eric Johnson, 32, have temporarily put wedding plans on hold, the former NFL player "feels like my husband already," the singer said. "We are just doing it a little bit backwards."

The Fashion Star mentor appeared on the talk show just one day after her star-studded baby shower. "It was a Charlotte's Web thing. We had a whole fair," the Texas native said. "We had fried Oreos!"

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Guests included mom Tina, sister Ashlee, and actresses Jessica Alba and Odette Annable. "Jessica received tons of gifts mostly wrapped in pink gift wrap and boxes," a source tells Us Weekly. "There were several books, stuffed toys and clothes among other items."

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