There's even more to love about Heidi Montag than there was Monday.

Literally.

The Hollywood Gossip has learned that the cute, vivacious, judgment-challenged star of The Hills has undergone breast augmentation surgery at the Beverly Hills, Calif., office of plastic surgeon Dr. Frank Ryan.

We repeat, Heidi Montag has breast implants.

Sources say Montag, the estranged BFF of Lauren Conrad, had been contemplating the procedure for several years now and just recently decided to go under the knife.

You go, girl.

An aspiring singer who is recording a pop album with record producer David Foster for release later this year, waited to have the procedure done until after The Hills' Season 2 concluded.

The show's finale, which aired Monday, showed Heidi Montag moving out of the apartment she shared with Lauren, to live with her boyfriend, Spencer Pratt.

That guy sucks. It's puzzling, in many ways, why Heidi Montag would get bigger boobs, since she already dates the biggest one in SoCal. Zing. Audrina Patridge, meanwhile, has moved in with LC.

"Heidi just doesn't want to make a big deal out of it," says a source close to the star. "She did this for herself, and she's hoping to keep it as private as possible."

We've learned Heidi is recovering well, but she couldn't be reached for comment. We hope she gets well soon. And dumps that ass Spencer Pratt.