Born in Belfast, Helen Mary Herbert (née Carson) moved with her family at an early age to South Africa and later to northern Kenya, where her father ran a mission hospital. She wanted to be a doctor and devoted her A-level work to analyzing the weight of the placenta in a maternity hospital built by her father. She was educated in Kenya and later moved to Cambridge, UK for sixth form, where she lived independently from the age of 16. At medical school in London, she was active in student life and excelled as an athlete who enjoyed hockey and teamwork. Her career was cut short by a knee injury while playing netball. She completed her first housework at St Mary's and began her ophthalmology career with masters at Moorfields, where she was later appointed to a senior position.