Kourtney Kardashian is counting her pregnancy pounds.

"I weigh myself every day," she told E! at the Kardashian Charity Knock Out in Las Vegas Tuesday night. "I've gained 26 pounds since getting pregnant, except I gained three pounds since yesterday."

The former runner -- who is expecting a boy with beau Scott Disick -- admitted it's "hard carrying extra weight."

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"Today I vowed that I was going to wear flats, and then last second, I threw on some heels," added the reality star, 30.

"I can't wait to sit down already," she went on. "I'm over the red carpet being pregnant!"

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Her step-dad Bruce Jenner said Kourtney -- who is due around Christmas -- will use the same doctor who delivered her.

"I have great confidence she will get through this -- that baby will be born," Jenner said. "But then the real tough stuff starts for her. You've got a little baby there for 24 hours a day, for the next 20 years!"