The 60-second clip, which Kardashian West shared on Twitter, features her speaking with sister Khloe Kardashian and then teasing, "What happens every time I say, 'Guess what?'"
Khloe Kardashian, 33, says it means someone is having a kid.
"We're having a baby!" Kardashian West then answers. The reality star and businesswoman, 36, did not say how they are having the baby or if they are using a surrogate as other outlets reported earlier this summer.
E! News, the network that hosts the family's show, also published the baby announcement.
This would be the third child for the Wests, who are already parents to daughter North West and son Saint West.
Kim isn't the only Kardashian who has been in the media lately regarding an expected baby. Last week, reports surfaced that Kylie Jenner, 20, is pregnant, and earlier this week, the same news circulated about Khloe Kardashian. However, neither has confirmed the news.