In the early to mid twentieth century there was constant conflicting medical advice about how a mother should feed her baby. At least now every major medical association (to my knowledge) recognizes that breast is best. But back then, the advice was not as cut and dry. Below is a WPA (Work Projects Administration) poster encouraging mothers to breastfeed. It was distributed in New York and created in 1938.
However, as the below poster reveals, other agencies and states had another agenda entirely. This is a poster from the Cleveland Division of Health and FDA promoting milk, showing a large bottle of milk next to couples smiling, playing golf, tennis, and two babies. It was distributed in Ohio and was also a part of the WPA Art Program, 1940.