Fielding returned to the University of Sydney to study medicine, completing a Bachelor of Science (BSc) in 1919, then a Bachelor of Medicine (MB) and Master of Surgery (ChM) in 1922.[1] In 1923 Fielding moved to London to work as a demonstrator in the department of anatomy at University College London, where she gained a reputation for both her competence and knowledge in the field of practical neurology.[2] She was encouraged to study monotremes (mammals that lay eggs) by the head of the anatomy department Sir Grafton Elliot Smith, and in 1925 she presented her first paper, on the marsupial mole, to the Anatomical Society of Great Britain and Ireland.[3]