#Demography

Groundbreaking demographic research reveals a powerful correlation between America’s declining religiosity and plummeting birth rates, adding crucial cultural dimensions to economic explanations for the nation’s fertility crisis while providing stark warnings for Thailand’s even more severe population challenges. Comprehensive analysis from leading research institutions, including extensive reporting synthesis by major news outlets, detailed demographic studies from the Institute for Family Studies, and new data from the Pew Research Center’s 2023-2024 Religious Landscape Study, demonstrates that highly religious Americans consistently maintain much larger families than their secular counterparts, while the growing population of religiously unaffiliated individuals has dramatically reduced their fertility to levels comparable with the world’s lowest-birth-rate societies. The fertility gap between religious and secular Americans has widened significantly over recent decades, with researchers calculating that virtually the entire decline in U.S. fertility from 2012 to 2019 can be attributed to growing irreligion combined with the exceptionally low birth rates among non-religious populations. Most critically for Thai readers, these findings illuminate how cultural and spiritual institutions provide essential social scaffolding for family formation—scaffolding that Thailand has been rapidly losing through urbanization, secularization, and changing social values, contributing to the kingdom’s catastrophic fertility decline that now threatens long-term economic stability and intergenerational support systems.

A growing body of demographic research finds a clear association between declining religiosity in the United States and the nation’s falling birth rate, adding a cultural dimension to well-known economic explanations for fewer children. Recent reporting and data syntheses – notably a long-form piece in Newsweek summarizing experts’ views, a detailed demographic analysis posted by the Institute for Family Studies, and new estimates from the Pew Research Center’s 2023–24 Religious Landscape Study – show that Americans who are more religious tend to have larger families, while the religiously unaffiliated have had markedly fewer children in recent decades. At the same time, the number of people who identify as nonreligious has grown, meaning the fertility gap by religion now helps explain a meaningful share of the overall decline in U.S. births. These trends matter to Thailand because Thai fertility has fallen even more rapidly, and understanding cultural as well as economic drivers can help shape policies to stabilise family formation and cushion the social effects of population ageing. See the Pew report here, the Institute for Family Studies analysis here, and the CDC’s 2023 birth data here.

The United Nations has sounded the alarm on an “unprecedented” worldwide decline in fertility rates, with profound consequences already shaping the future of nations like Thailand. The latest United Nations Population Fund (UNFPA) report signals a tipping point: hundreds of millions of people worldwide are having fewer children than they would like, often citing rising financial pressures and shifting social dynamics as key barriers. For Thailand—a country at the heart of regional demographic shifts—the findings carry urgent weight, offering both fresh validation of local experiences and serving as a catalyst for renewed policy action.

Sangamon County, located in central Illinois, is grappling with its first population decline in two centuries—a development that has community leaders sounding the alarm and seeking innovative solutions to reverse the trend. According to recent remarks by the County Board Chair at a chamber of commerce luncheon, the region—best known as the seat of the state capital Springfield—has lost approximately 1,000 residents over the past decade, a decline that is especially pronounced among young people and working-age adults (newschannel20.com).