Kim Kardashian admits her sex tape helped "introduce" her to the world.

A raunchy clip of the reality TV star with her then boyfriend Ray-J was leaked in 2007.

Kim remains embarrassed that the intimate moment has been seen by people around the globe, although in an interview with Oprah Winfrey which aired in the US yesterday she admitted it did springboard her career.

"That's pretty much how I was introduced to the world. It was a negative way, so I feel like I had to work ten times harder to get people to see the real me," Kim said.

She felt "humiliated" when the video went public, adding she isn't sure how she would have coped with talking to her late father about it had he still been alive.

Kim has continued to cause controversy, having split from her basketball player husband Kris Humphries last year after a 72-day marriage. She suffered a backlash following the break-up, with some claiming she wed to make money.

"We don't do anything for ratings. I think anyone who knows me knows that I fall in love hard," she said. "I would have had a big wedding regardless of who I am.

"Once we moved in, I knew that he was not the one."

Oprah also interview Kim's siblings Kourtney, Khlo and Rob and her mother Kris Jenner.

Kourtney claimed to be uncomfortable with fame, which Oprah doubted. The interviewer then quizzed the brothers and sisters on Kris' divorce from their father Robert Kardashian.

Kourtney who is expecting her second child with her boyfriend Scott Disick said it had a big impact on her.

"Maybe I'm kind of scared of marriage because of that," she mused. "I'd like to [get married] someday for my children... but I know I'm just as committed if I'm married or not married."

Kourtney later took to Twitter to discuss how fun the sit-down talk had been.

"The way @Oprah asks questions is so genius. She really made us so comfortable talking to her. That's why she's Oprah! Who watched our interview (sic)?" she wrote.