Heidi Montag, reality show star turned plastic surgery spectacle, has gone under the knife again -- this time, for medical reasons. The 27-year-old former "Hills" star reportedly underwent a breast reduction that decreased her bra size from an "F" to a "D."

Montag filmed her surgery for "Entertainment Tonight." Host Brooke Anderson posted a photo of herself and Montag on her Twitter Thursday, writing: "We r in the OR w/@HeidiMontag tn on @ETonlineAlert as she downsizes from F breasts to D for health reasons!"

This isn't the first time Montag has publicly documented her plastic surgery operations. In 2010, the then 23-year-old unveiled a shocking head-to-toe makeover in a People magazine cover story, in which she claimed to have undergone 10 procedures in just one day, including rhinoplasty, liposuction, breast implants and buttock augmentation.

She would later regret her many operations, telling Billy Bush on "Access Hollywood" in 2012: "I would never do it again and I never recommend it for anyone … I kind of wanted a few enhancements and then it got out of hand. I wasn't told really the repercussions and what would happen, emotionally and psychically and the pain I would be in. I was kind of in shock."