Khloe Kardashian is ''traumatised'' after hearing her mother have sex with Corey Gamble.

The 'Keeping Up with the Kardashians' star was horrified when she and sister Kim Kardashian West went into 57-year-old Kris Jenner's house only to realise she was getting intimate with her 34-year-old boyfriend.

Khloe said: ''Hearing them have sex is wild and I'm traumatised. Kim and I did.

''At her house, thank god. We were downstairs, and we just heard like [claps]. It's really a traumatising thing. And the headboard just going....We were hitting each other like, 'NO!' Kim was like, 'Wait, shh.' And then it was dead silent and then they went again for round two. I was like, 'OK, check please, I'm gone.' ''

And the 31-year-old star admitted it wasn't the first time she had heard her making love, and she even accidentally found herself in the same room as her mother and stepfather Bruce Jenner - who is now known as Caitlyn since undergoing a gender transition - when they were having sex.

She added to Complex magazine: ''That shouldn't happen to anybody, but it's happened to me a few times with my mom. When I was younger, I was hiding under my mom's bed for some reason, and her and Bruce started having sex. I was there and I couldn't leave. I had to stay until it was over.''

While Kris is happy in her relationship with Corey, Khloe thinks it is ''disgusting'' and ''weird''.

She said: ''When I found out she was dating, or even texting back and forth, it was so weird to see her giggly.

''I'm like, 'How do you flirt? Like, what do you guys say?' And it is disgusting. It's awkward.

''Why is a 32 year old, or whatever he is, why is he talking to a 50-fabulous-something woman? That's just -- and I say it to her all the time -- weird.''