Born in Bad Axe, Michigan, Karen Uphoff began her ballet training at the age of ten in Olympia, Washington. She continued her training with Margaret Newcomb and Rene Gillenwater in Killeen, Texas. Uphoff also studied with Ludmila Morkovina and Alla Sizova as a scholarship student at the Kirov Academy in Washington, D. C.
Before joining American Ballet Theatre as a member of the corps de ballet in 2003, Uphoff danced with the Colorado Ballet. Her repertory with the Company includes the Fairy Winter in Frederick Ashton's Cinderella, Rosaline in Romeo and Juliet, the Queen in The Sleeping Beauty, the Queen Mother and a big swan in Swan Lake, Anna in La Sylphide, Terpsichore in Sylvia, roles in Black Tuesday and Everything Doesn't Happen at Once and a leading role in Sechs Tänze.