Final answer:
Ignaz Semmelweis identified that proper hand hygiene, particularly washing hands with chlorinated lime water, significantly reduced puerperal infections among birthing mothers.
Step-by-step explanation:
Semmelweis discovered that puerperal infections could be prevented by proper handwashing. Ignaz Semmelweis, a Hungarian obstetrician, observed a high mortality rate due to puerperal fever among women who had been attended by doctors. These doctors would often go from performing autopsies directly to delivering babies without washing their hands. Through careful observation, Semmelweis inferred that doctors were transferring some form of contagion from the autopsies to the birthing mothers. He implemented a protocol that required physicians to wash their hands with chlorinated lime water, which led to a dramatic reduction in the maternal mortality rate from puerperal fever in the hospital where he worked. Despite being initially disregarded by many of his contemporaries, Semmelweis's work laid the groundwork for aseptic techniques and highlighted the importance of hand hygiene in medical practice.