Factors in the Drop in United States Infant Mortality: 1900-1940

This paper examines the causes of the steep drop in United States infant mortality, 1900-1940. I consider the country’s national experience, as well as the local experience of Pittsburgh. In Section One, I present historical evidence on potential factors in the infant mortality drop. In Section Two, I estimate the effect of several of these factors on the United States infant mortality rate, as well as the Pittsburgh infant mortality rate. I find that the cleaning of market milk and the cleaning of drinking water are associated with significant decreases in infant mortality. My analysis suggests that the effect of the national cleaning of market milk was greater than the effect of the cleaning of water.