Heidi Montag had "part of [her] chin sawed off" during her infamous cosmetic surgery makeover.

The 37-year-old reality star underwent a shocking 10 procedures - including a chin reduction, breast augmentation, brow lift, liposuction, rhinoplasty, and facial fat injections - in just one day back in 2009 and she's admitted now she hadn't realised just how long it would take her to recover or how much of an impact the operations would have on her life.

Speaking on PageSix’s 'Virtual Reali-Tea' podcast, Heidi said: “At the time, my surgeon was like, ‘Oh, it will be a quick recovery, a few months.’ And it took me over a year to heal, so I could barely talk [with] my jaw.

“I just had part of my chin sawed off. It was really a lot just dealing with that.”

Heidi had previously undergone a nose job and breast implants, so expected her recovery to go as smoothly as when she'd had those procedures, so was horrified when she realised she wouldn't be fit enough for filming on the sixth and final season of 'The Hills', on which she starred with husband Spencer Pratt.

She said: “I wasn’t even in a place [to film]. And I kept saying, ‘I’m not a person right now. I need to heal and recover and I’m not doing well physically.’ Like, I’m not able to show up like I was.

"I thought I’d bounce back and be able to be on TV like I was after my first cosmetic surgery. But there was just way too much done and each thing took too much time and it hurt so bad.

“I was just in such an immense amount of pain."

Acknowledging the operations were “obviously [her] choice,” Heidi confessed she wasn’t “aware of the repercussions” of what she was going through, leading to her and Spencer ultimately pulling out halfway through filming the show.

She said: “We had to have nurses at the house for months to help me recover.

“So we’re dealing with that and then we have these producers like, ‘Say this and that.’ And we’re like, ‘We can’t do this.' "