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We tentatively conclude that the decline in fertility across recent cohorts in high-income countries is likely the result of evolving norms, expanding choices, and the role of broad social and economic influences. This multi-faceted cohort-based explanation contrasts with narrower period-specific explanations focused on the role of prices, income, and the opportunity cost of women’s time. Those standard types of explanations are likely important at a micro level, but to understand the widescale decline in fertility and rise in childlessness across recent cohorts requires a wider lens.

Beyond this tentative conclusion to the posed title question, we offer the following additional suggestions for future research among economists interested in this area of study - p. 39 First, future work in economics into the decline in fertility would benefit from more fully integrating demographic insights. As noted above, demographers have often focused on the mechanics of fertility trends and have long emphasized the importance of understanding lifecycle patterns in fertility at the cohort level, including distinctions between timing, total number of children ever born, and childlessness. Economists often emphasize the causal behavioral determinants of fertility outcomes. Both perspectives are essential for a comprehensive understanding of fertility patterns and the integration of the two is likely to be the most productive path forward for advancing understanding.