Real Housewives of Beverly Hills star Kyle Richards opened up about her recent surgery after Andy Cohen accidentally spilt the news live on air.

The Watch What Happens Live with Andy Cohen host was interviewing Richards, 53, and Saturday Night Live star Chloe Fineman, 33, on his Bravo show on Wednesday evening when he let slip about his guest's surgery.

During a segment of the show, Andy innocently asked: "How’s the breast reduction working out?"

To which Kyle immediately quipped back: "Oh, thank you for letting everyone know, Andy. Thank you."

Cohen was left mortified by his revelation, covering his mouth in disbelief by his actions.

He responded: "Oh my God. I thought you talked about it. But you’ve told me about it so many times! I’m so sorry!"

Fineman and the audience were laughing in hysterics by Cohen's gaffe but Richards stayed calm as she explained the reasons for going under the knife.

"I text Andy all the time. I’m just going to say this… I never told anybody," she said.

"I still don’t have an implant but I went in and I said, 'I want smaller boobs and I don’t ever want to wear a bra ever again in my life', and here I am!

"So I have smaller boobs, even though you can’t really tell because they’re still swollen, but I will never wear a bra again!"