Karembeu was born in Brezno, a town in central Slovakia (then a part of Czechoslovakia). Having originally studied medicine in Prague, she gave up her studies to become a fashion model at the age of 26.
She was hired as one of the models for the Wonderbra, and she was popular in Europe for her Wonderbra billboards. In the United States, she modeled for Victoria's Secret. She is also in Guinness book of records for longest legs in the world.