The 33-year-old television personality shared the news on the Season 14 finale of Keeping Up with the Kardashians, which aired Sunday.
The episode shows Khloe's sister Kylie Jenner giving the star the news over the phone. Khloe, who was convinced she was having a boy, appears somewhat unenthusiastic as she reacts with sisters Kim Kardashian and Kourtney Kardashian.
"You're lying," Khloe tells Kylie before asking Kim, "Is she lying or is she serious?"
"I don't feel like I'm having a girl," Khloe adds. "I don't feel like I'm having a girl at all. I'm, like, in a state of shock."
Khloe said on Twitter after the episode that she is thankful to be expecting a girl. She added that she's "so excited" for her daughter to grow up with Kim's younger daughter, Chicago West, and Kylie's daughter, Stormi.
"God gives us what we need! His timing is never wrong! my hormones were IN RARE FORM for that news," the star explained of her reaction.
"I am now so excited my daughter will have forever best friends with Chicago and Stormi!! God is great!!! Thank you Lord for our princess," she wrote.
Khloe confirmed her pregnancy in December following months of speculation. She drew criticism last week for traveling to Japan with Kourtney and Kim ahead of her due date.
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