DATELINE: ANCHORAGE—BRISTOL PALIN confesses to facial surgery that drastically altered her appearance.

The Teen Prego Queen of Wasilla, 20,  and Sarah Palin's daughter told a glam fan mag she  underwent corrective jaw surgery in December, a month after she cha-cha-ing into third on "Dancing with the Stars."

Her once cherubic face now appears thinner, with higher cheekbones and an angular jaw.

New look Bristol sporting a frame 5 pounds lighter debuted April 30 at the White House Correspondents' Association dinner in Washington, D.C.

"Yes, it improved the way I look, but this surgery was necessary for medical reasons," Bristol admitted to Us Weekly.

Palin claimed she had the procedure so her jaw and teeth could properly realign.

While growing up, she says, she wore braces and a retainer to help correct an overbite. But she said her dentist warned her that she'd have to have major surgery one day.

"I look older, more mature and don't have as much of a chubby little baby face.

"I wouldn't get plastic surgery unless I got in an accident or something terrible and got disfigured," she said.

As The ENQUIRER reported Bristol will star in a new “reality:” show for Bio net with new fake roomies Kyle and Christopher Massey.

POP FYI: A girl once named Norma Jean had her jaw broken and realigned by docs before finding fame as Marilyn Monroe