Former Biggest Loser contestant Kristin Steede is going to be a mom!

The season 7 contestant -- the largest woman in Biggest Loser history to compete on the show at the time of her 2009 run -- announced her pregnancy via her blog Thursday. It is the first baby for Steede and her husband of five years, Nick.

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"I have taken three home pregnancy tests," Steede, 28, wrote of finding out she's expecting. "After the third positive test and squeezing my sore tender breast about a million times it finally sunk in that this was real."

Weighing in at 360 pounds when she first began training with Bob Harper at the Biggest Loser ranch as part of the NBC series, Steede says her pregnancy would not have been possible had she not shed the pounds.

Watch a VIDEO of the Biggest Loser stars sharing their weight-loss secrets

"I truly believe with all of my heart that my weight was the one thing that prevented us from starting our family sooner," she said. "I also believe that if it were not for the Biggest Loser I would not be experiencing this miracle today."

Steede competed on The Biggest Loser with her mom, Cathy, as part of the show's couples season, and was the first woman ever to lose 100 pounds during training.

See stunning before-and-after shots of Biggest Loser contestants

The newest Biggest Loser will be crowned when season eight wraps on Dec. 8.

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