A Throughput-Based Demographic Projection Model for Childlessness in the United States and West (2025–2050)

This technical note introduces a throughput-based demographic projection model to analyze the rise of biological childlessness among women aged 25–44 in the United States and across major developed regions. Unlike traditional fertility models that emphasize cultural or attitudinal factors, this framework treats childlessness as a structural outcome of accumulated socio-economic incoherence (N) and limited institutional throughput (¥). When incoherence persistently exceeds throughput capacity, reproductive timing collapses and childlessness rises. Using empirical baselines from U.S. Census, CDC, and academic research (2014–2024), the model projects that by 2030, 45–50% of U.S. women in reproductive age may be childless, with the threshold plausibly surpassing 50% by 2035. Comparative analysis across Western Europe, the Anglosphere, and Northeast Asia reveals converging trajectories toward post-fertility equilibria, with Northeast Asia already entering systemic collapse. The findings highlight childlessness as a mathematically traceable demographic equilibrium, shaped by structural constraints rather than cultural volatility, and identify policy levers focused on reducing household formation costs, mitigating legal-financial risks, and expanding childcare throughput.