Kylie Jenner is pregnant with her first child, according to US media.

The 20-year-old reality star and her boyfriend rapper Travis Scott, 25, have reportedly shared the news with family and friends.

The couple have been dating since April.

TMZreported, citing a source, that Scott recently spoke about the pregnancy at an event and how his life was going to change.

People magazine reported that Jenner, who has a mass social media following, is said to be surprised but "really excited" about her pregnancy.

It quoted a source close to her family as saying: "It is an unexpected but completely amazing turn of events that she could not be more excited or thrilled about."

Jenner came to prominence after appearing on the US reality show Keeping Up With The Kardashians.

It focuses on the lives of her sisters Kim, Khloe and Kourtney Kardashian, Kendall Jenner, and mother Kris Jenner.