Following her fellowship, Dr. Hazan returned to Montreal and opened a practice in upstate New York. Her work there consisted of 10 percent research and 90 percent private gastroenterology patients and brought many patients from across the border in Canada. She was the only female gastroenterologist in an 80-mile radius, and the influx of Canadian patients brought to light for her the problems with socialized medicine in Canada. These patients faced intolerable wait times for a visit with a gastroenterologist in Canada, and so visited Dr. Hazan in New York. After meeting with the Prime Minister of Health, Dr. Hazan helped bring about a dual system in Canada, in which private practices co-exist with socialized medicine. Her years of practice as a solo woman gastroenterologist brought her under the microscope on numerous occasions, facing scrutiny not encountered by her male colleagues.