Fewer children, better futures: How war shapes family choices

Background: Most research on the demographic impact of war focuses on how highly disruptive conflicts impact family life, often overlooking how less destructive wars shape family strategies. Understanding family adaptation in these contexts is essential for a nuanced view of war’s demographic effects. Objective: This study examines whether exposure to the Spanish Civil War (SCW) led families with reproductive flexibility to shift from larger families to a greater investment in childhood quality. Methods: We use retrospective microdata from the 1991 Spanish Sociodemographic Survey, applying regression discontinuity designs to exploit variation in exposure to the SCW by birth cohort and provincial violence intensity. Outcomes analyzed include sibship size, child labor, and early child mortality. Results: Exposure to the SCW reduced family size and improved child outcomes – less child labor and reduced early child mortality – especially among families with greater reproductive flexibility and in high-violence provinces. Robustness checks confirm that these effects are not driven by modernization and other secular trends. Conclusions: When children are not explicit targets of violence and families retain certain agency, wars can prompt a strategic shift toward fewer, better-supported children. These adaptive responses concentrate among families able to adjust their reproductive plans and in areas most affected by violence. Contribution: This study challenges the assumption that wars uniformly harm child development. By highlighting family adaptation during less disruptive conflicts, it expands understanding of the demographic consequences of war and underscores the importance of conflict heterogeneity and family agency in demographic research. Our approach can also be applied to ongoing conflicts where violence does not primarily target children.