Over the course of the last 100 years, American childbearing has changed dramatically.
American women reaching childbearing age around 1890 averaged 4.2 live births during
their reproductive years. For women reaching childbearing age a century later, this number
had fallen to a stable 2, just below replacement levels. 1 The US baby boom temporarily
reversed this trend. Between 1940 and 1960, the general and total fertility rates rose by 60
percent and cohort measures of completed fertility rates rose by 45 percent.