Sophie Pasteur began her career as a nurse and midwife, working at the Hôpital de la Maternité in Paris. Her experience in the medical field, combined with her family's connections, eventually led her to work alongside her uncle Louis Pasteur. Sophie became an integral part of his research team, assisting him with experiments and providing care to patients in his studies. Her work with Louis Pasteur not only honed her skills but also gave her a deeper understanding of the importance of hygiene and sanitation in medical practice.