He did not want such stories appearing in the popular press, as these reports might frighten women. DeLee was one of the pioneers of filmmaking for the purpose of medical teaching. He authored a paper in the mid-1930s, "Sound Motion Pictures in Obstetrics", which described the necessary components of a medical film, including scripts, props, lighting, sound and expert staff members. DeLee was employed with Northwestern University until 1929, when he aligned with the University of Chicago. DeLee authored several editions of "Principles and Practice of Obstetrics", which was described as "unequalled in text and illustration." DeLee created "Our Baby's First Seven Years", a book that parents could use to record the milestones of infancy and childhood. The book also provided child care advice. More than eight million copies of the book had been sold by 1987. William S. Kroger, who DeLee successfully revived as a newborn in 1906, graduated from medical school in 1930 and served a residency under DeLee in obstetrics, gynecology and neuroendocrinology. Since his childhood, Kroger had been urged by his mother to follow in the footsteps of the doctor who had saved his life. Kroger became a well-known authority on the use of hypnosis in obstetrics and other medical specialties. In 1934, the University of Chicago recognized DeLee with its Rosenberger Medal, which is awarded for excellence in research, invention, authorship or other distinctions that benefit humanity. DeLee became an emeritus professor at the University of Chicago in 1935. In May 1936, DeLee appeared on the cover of "Time" magazine. He died at his Chicago home in April 1942. DeLee never married and he was said to have lived constantly at the hospital. Author Harold Speert wrote, "Despite his wide professional acclaim, DeLee remained a lonely unhappy man, plagued by excessive sensitivity and by the compulsive tendencies of the perfectionist he was." In 1948, a mothers aid group from the Chicago Maternity Center raised $30,000 to endow a professorship in obstetrics in DeLee's name at the University of Chicago. The board of directors for the Chicago Lying-in Hospital awards the Joseph Bolivar DeLee Humanitarian Award annually to an individual who has made significant contributions to the care of women and children. DeLee's nephew, Sol DeLee, was a Las Vegas obstetrician who wrote several editions of the book "Safeguarding Motherhood" from the 1940s to 1980s.