“It's kind of a miracle that I even got pregnant,” she told Kathie Lee Gifford and Hoda on the US Today show on Tuesday.

“'It was a pleasant surprise when so many doctors were telling me one thing and then the opposite happens.”

Kim’s younger sister Khloe has also suffered fertility issues in the past and has been open about her struggles to fall pregnant with her husband Lamar Odom.

“Khloe has been very open about her fertility issues and I think I was always really kind of quiet about mine, and I have similar issues,” Kim said.

She says she still finds it difficult to believe she is pregnant.

“I think until I really start seeing, like, a belly, it won't really sink in. It's just like a weird realisation until you really start seeing the physical changes, um, and every day's different,” she said.

Although the 32-year-old is looking forward to welcoming her first child with singer Kanye West, there is one thing still bothering her – her failed 72-day marriage to basketball player Kris Humphries.

The pair are yet to finalise their divorce, as Kris is refusing to sign the necessary papers.

“I can't speak for anyone else [about why the divorce hasn’t been finalised]. It's a process... It's happening, hopefully,” she said.

Kim says she has discussed marriage with Kanye but for now they are “focusing on the baby”.

“[I'm] so content with how things are right now. And how life is and we're so happy. We definitely want [marriage] in the future, but I'm not in a rush.”