The Baby Boom and Its Explanations

This article examines explanations of the sharp rise in the birth rate that occurred in the United States during the late 1940s and the 1950s (the so-called “baby boom”) in light of recent research on the nature and magnitude of its demographic components. The paper includes a review of the fertility surveys that derived from concern about postwar fertility trends, a discussion of the kind and relative importance of the demographic components constituting the fertility increase of the period, an assessment of explanations of the baby boom, and a reinterpretation of one of the components—the rise in average family size—that was a demographically small, but theoretically significant, part of the upturn in the birth rate.