Dr. Spears studied for her BSc (Hons) at the University of Edinburgh, followed by a DPhil at Oxford University, supervised by John Clarke. After two years in Irv Zucker's laboratory at the University of California at Berkeley, and a year in the Brain Metabolism Unit in Edinburgh, she moved to Physiology at the University of Edinburgh. She has worked there since 1990, using animal models to investigate reproductive physiology, holding an MRC Training Fellowship, followed by a Royal Society University Research Fellowship, until she took up a University position in the Centre for Integrative Physiology in 2002. Her current work investigates the effects of chemotherapy treatment on female and male gonads, using a variety of tissue culture techniques.