Final answer:
Ignaz Semmelweis observed the higher mortality rate of mothers from puerperal fever in hospital wards compared to those attended by midwives. He suspected that doctors were transmitting the disease, and handwashing procedures greatly reduced mortality rates.
Step-by-step explanation:
In this historical case, the subject is Medicine. The case discusses the work of Hungarian obstetrician Ignaz Semmelweis in 1847. Semmelweis observed that mothers who gave birth in hospital wards staffed by physicians and medical students had a higher mortality rate from puerperal fever compared to mothers in wards staffed by midwives. He suspected that the doctors were transmitting the disease due to poor hand hygiene, and when handwashing procedures were implemented, the mortality rate decreased significantly.