Kourtney Kardashian is thinking about having a natural childbirth.

"I used to think, 'Oh, just get a C-section and it's done and easy and whatever," the pregnant star of Kourtney & Khloe Take Miami tells E!. "I've already changed since before being pregnant."

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Kardashian, 30, admits she's "scared" around babies. At a recent lunch with her sister Khloe and a pal and her baby, she was hesitant to even hold the infant, she says. "Khloe knew everything to do, like holding her perfectly, playing all these games. The girl was laughing," Kourtney says. "When I tried to hold her, I was like, 'Khloe, take her, take her!' I was so scared."

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Kardashian hasn't had a lot of practice with kids. "I don't think I have ever changed a diaper," she says. "I am sure that I helped with [younger sisters] Kendall and Kylie, but I don't remember. When Kendall was born, I was 16. You just get your license then and you're never home."

Her day-to-day life has become exhausting, says Kardashian, who is due around Christmas. A recent trip to Beverly Hills deli Nate & Al's knocked her out. "I got tuna on a bagel and pickles and sauerkraut and then bagel chips dipped in thousand island dressing. But after that, I literally went home because I was so tired. I made Scott come home and take a nap with me," she laughs of her baby's father, Scott Disick.

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Kardashian also opens up about wedding Disick. "We talk about [marriage] all the time," she says. "I just feel like there is so much to do. There is no rush. We should do everything for the baby right now and I'll worry about myself later."

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