An early proponent of hygienic standards during childbirth, DeLee even advocated for the construction of separate hospital buildings for labor and delivery.

DeLee believed that mechanical intervention (such as forceps delivery) could prevent the poor outcomes that sometimes resulted from childbirth in the late nineteenth and early twentieth centuries.

DeLee pioneered medical filmmaking as a teaching tool in medicine and he invented a device used for several decades to suction the airways of newly born infants.

[4] After completing an internship and a trip abroad for postgraduate studies, DeLee was ready to set up a medical practice by the age of 25.

[2] Sanfilippo and Uppal write that, after he paid the first month's rent at the new Ashland Boulevard facility and purchased the necessary equipment, DeLee was left with sixty-one cents to his name.

The pediatricians – influenced by their experiences taking care of other types of malnourished children – thought it was essential for the babies to be exposed to sunlight.

By 1901, DeLee had built an entire incubator transport service staffed with specially trained nurses, but costs were high and maternity hospitals still did not attract many private patients.

[7] In the early twentieth century, DeLee observed that obstetric complications and deaths were so common that he "often wondered whether nature did not intend women should be used up in the process of reproduction, in a manner analogous to that of the salmon, which dies after spawning.

If you adopt this view, I have no ground to stand on, but, if you believe that a woman after delivery should be as healthy, as well as anatomically perfect as she was before, and that the child should be undamaged, then you will have to agree with me that labor is pathogenic, because experience has proved such ideal results exceedingly rare.

"[8] In 1915, at the annual meeting of the American Association for the Study and Prevention of Infant Mortality, DeLee spoke out against the use of midwives for childbirth.

[9] At a meeting of the American Gynecological Society in 1920, DeLee sparked controversy when he presented a paper advocating for the use of a systematic approach to childbirth for physicians, including the use of forceps and episiotomy even in women who had no labor complications.

With a maternal mortality rate about one-quarter of the national average, DeLee's Chicago Lying-In Hospital became well-respected and influential, and medical students would travel across the country to gain some experience there.

[2] David Hillis, one of DeLee's colleagues at the Chicago Lying-in Hospital, published a 1917 journal article about his invention of the fetoscope, also known as the head stethoscope.

[16] Despite the initial resistance DeLee faced from his colleagues over his standardized, invasive approach to delivery, forceps began to appear in routine obstetric practice in the 1930s.

As childbirth was still beset with problems such as childbed fever, physicians were asserting their superiority over non-physician birth attendants, and mechanical interventions in obstetrics set their profession apart from midwifery.

Such proposals were met with great criticism by influential physicians such as J. Whitridge Williams, who said that DeLee's precautions represented "a degree of caution that approaches 'infectio-phobia'.

In a letter to journalist Paul de Kruif, DeLee even wrote that he was "perfectly willing to repeat that general hospitals are cesspools of infections, but only in a medical journal.

[22] In 1934, the University of Chicago recognized DeLee with its Rosenberger Medal,[23] which is awarded for excellence in research, invention, authorship or other distinctions that benefit humanity.

[26] 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.

Busy physicians were often eager to adopt this systematic approach to anesthetized delivery because its efficiency allowed them to care for more patients.