Does female fertility rate track turning points in our cultural history?

A graph of the U.S. fertility rate since 1909 recently appeared under the headline, “The U.S. fertility rate reached an all-time low in 2023.” While that statement is true, it understates what is most striking about the data. At a glance, the graph shows that fertility has been relatively stable since about 1970. Before that, however, the pattern was far more dramatic: a steep decline from roughly 1920 to 1933, a strong rebound from about 1941 to 1960, and then another sharp fall from 1960 to 1975, after which the rate leveled off (see figure below). The question is what...