Religious people have fewer children in secular countries

A country's cultural values, social norms and policies influence how many children people have—particularly among the religious, new Cornell research shows.

The analysis finds fertility rates are lower in secular countries, but not simply because they have more secular people, who have fewer children on average. In addition, very religious people in the most secular countries have significantly fewer children—about half as many—than if they lived in the most religious countries.

That country-level variation reveals that "societal secularism" is a better predictor of fertility rates, the study suggests, than surveys of individuals' religiosity or secularism, the basis of most studies and demographic predictions to date related to religion and fertility behavior.

"A country's characteristics matter for fertility rates, not just individuals' characteristics," said Landon Schnabel, the Robert and Ann Rosenthal Assistant Professor of sociology in the College of Arts and Sciences. "People face different influences, make different choices and engage in different behaviors depending on where they live. In short, characteristics of a society can end up shaping individual behavior."

Schnabel is the author of "Secularism and Fertility Worldwide," published July 16 in the journal Socius.

The study's findings have implications for religious change over time and for understanding some post-industrial countries' low fertility rates, he said. They also support demographic research suggesting that the spread of secularism is self-limited by the fact that people in more secular countries have fewer children.

Schnabel said he was curious about whether where one lives influences fertility rates, and specifically whether living in more secular countries is predictive of people having fewer children.

To answer those questions, he created a dataset that estimated the proportion of agnostics or atheists in 181 countries, assembled from sources including the World Christian Database, United Nations and the CIA's World Factbook. He also examined data from the World Values Survey, which asked people in 58 countries about their religious views, including affiliation, belief in God, attendance of services and the importance of religion in their lives.

After controlling for factors such as economic development, education, and globalization, he found that people in secular countries do have fewer children.

The most secular people, the data showed, will typically have about the same small number of children regardless of where they live—below the replacement rate of 2.1. The biggest difference in behavior was seen in the most religious people, who are predicted to have nearly twice as many children in a very religious country versus a very secular country, Schnabel determined.

Why might that be? More secular countries promote greater autonomy for women's lives and bodies, Schnabel wrote, while in more religious countries, cultural values and norms tend to promote bigger families, reluctance to use modern contraceptives and abortion, and sometimes even explicit injunctions to "be fruitful and multiply."

Secular societies influence the fertility behavior of the religious more than the other way around, Schnabel theorized, because their gender values create opportunities for all women to pursue careers and other opportunities that make having fewer children an advantage. They also provide greater access to reproductive control.

In secular countries, immigration could offset lower fertility rates but tends to attract more religious people, potentially making the countries slightly more religious. Leaving religion is more common in secular countries, but they have fewer religious children who might consider doing so.

"These trends could limit the secularization of the global population over time, with very secular countries tending to have populations that are not growing or perhaps even shrinking over time," Schnabel said. "Whereas very highly religious countries have very fast-growing populations and are making up a larger part of the global population over time."

Forces that could potentially overcome the factors limiting secularism, he said, include the internet and media rapidly exposing religious people to secular ideas and culture, or regime changes.

Schnabel said his study adds to explanations for why fertility rates dropped significantly in some countries, including in Southern Europe and East Asia, starting in the 1990s. The phenomenon referred to as "lowest-low fertility" has generated many theories related to factors such as autonomy, self-fulfillment, gender equity and idealizing development—all of which are intertwined with secularism.

"Many of these countries with very low fertility tend to be very secular," Schnabel said. "It could be that secularism is a part of why fertility has gotten so low in some contexts."