Susan qualified in medicine from Queens' University in Belfast in 1990. She specialized in general practice in 1993, became a Diplomate of the Faculty of Sexual and Reproductive Health, and developed an interest in the intersection of gender and medicine. She undertook a BA (Hons) in Women's Studies and Sociology at Anglia Ruskin University and was awarded a PhD in Sociology at the University of Cambridge in 2010. Her PhD title was The Effect of Gendered Body Image upon Contraceptive Outcomes.
She continues to work at the intersection of medicine and sociology, with a particular interest in gender.