Vayena was born in Greece and grew up on the island of Lefkada. Vayena received a B.A. in history from the University of Athens, Greece and an M.Sc. in history of science, technology & medicine from Imperial College, University of London. Her master's research was on In vitro fertilisation where she examined the impact of new developments and the ethical questions. She then moved to the United States where she earned a Ph.D. in the social history of medicine from the University of Minnesota.
