Bertha Van Hoosen was born and raised on her family's farm in Stony Creek, Michigan. She graduated from high school in Pontiac and wanted to continue her education; as her parents refused to support her, she had to take various jobs to pay her own way, including teaching calisthenics at a high school. In 1884, she received her bachelor's degree from the University of Michigan and enrolled in the medical school, where she worked as a teacher and obstetrical nurse. She earned her medical degree in 1888, and then did her residency at the New England Hospital for Women and Children in Boston. In 1892, Dr. Van Hoosen opened her own private medical practice in Chicago, specializing in obstetrics and gynecology. She also taught at the Medical School of Northwestern University and was an assistant at the Columbia Dispensary. In 1902, she became a professor of clinical gynecology at the Illinois University Medical School, despite the opposition of the male faculty. She taught sex education and promoted the use of anesthesia for childbirth, and promoted the importance of hygiene and sterilization of medical instruments to prevent infection. She was outspoken about the medical profession's discriminatory treatment of women. and created a meeting among medical women that led to the founding of the American Medical Women's Association in 1915, with herself as the first president. In 1918, she was named head of obstetrics at Loyola University Medical School, making her the first woman in the USA to head a medical division at a co-educational university. In 1947, Dr. Van Hoosen published her autobiography, Petticoat Surgeon, detailing her pioneering role in medicine over 60 years.