Air pollution reduces fertility intentions of female migrants in China's cities

Global fertility decline is linked to shifts in women's childbearing attitudes, shaped by their perceptions of the child-rearing environment. China's recent fertility decline provides a context to explore this, and we build on the theory of planned behavior to examine air pollution's role in shaping female migrants' fertility intentions. Using instrumental variables to address endogeneity, a one-unit increase in air pollution is associated with a 1.722-unit reduction in their fertility intentions. This relationship shows heterogeneity: the adverse effect is strongest in cities of southern China, and among younger, highly educated, first-married female migrants without children. Mechanistic analyses reveal that air pollution harms female migrants' health, directly lowering their fertility intentions. Additionally, China's hukou system and insufficient family support worsen social inequalities, amplifying their vulnerability to pollution. Reduced fertility intentions amid worse pollution reflect their dissatisfaction with such inequities and inadequate support. Our findings highlight how environmental stressors interact with social inequalities to reshape reproduction, calling for integrated policies.