Lena Einhorn started out as a physician, with a PhD in Virology and Tumor Biology from the Karolinska Institute, Stockholm. Her research ranged from tumor viruses, to the question of what it is in embryonic life that so strongly inhibits the development of cancer in fetuses and newborns (Biomedical articles). In the late 80s, she changed professional course entirely. Living in the United States, she started working as Medical Editor at Lifetime Television in New York, where she eventually also started producing and writing medical documentaries. She continued producing documentaries in science and medicine, for independent production companies as well as for PBS.