In April of 2018, Avengers: Infinity War stunned critics and audiences with one of the most terrifying cinematic cliffhangers of all time. The all-powerful infinity “snap” that caused many of the film's main protagonists, along with half of its living Universe, to disappear into thin air. While the prospect of an infinity “snap” isn’t looming over Earth and its heroes today, there is a much more subtle danger that may threaten the same terrible end as the one perpetrated by the villain Thanos himself: The gradual, steady decline in childbearing worldwide.
A few decades ago, the story looked different. In the baby-boom years after World War II, the American fertility rate hovered well above 2.1, the number demographers call the Replacement Fertility Rate (RFR), or, in other words, the number of births (per woman) needed for any population to replace itself [1]. Neighborhoods overflowed with strollers and station wagons; schools scrambled to add classrooms. For better or worse, a mother rearing multiple children was a societal expectation.
Since the turn of the 21st century, births per woman in the United States have fallen significantly. The Aspen Institute's Economic Strategy group reports a steady decline since 2007, with the fertility rate sitting well below replacement in 2025 [2]. In The New Economic Reality: Demographic Winter, a documentary which aired on BYUtv, economists, demographers, and religious leaders were stitched together to determine why fertility rates were lowering and what the effects would be of such a decline [3]. The documentary's claim was shocking to many: the “population bomb” that we went off during the baby boom never actually exploded; instead, we have quietly been engineering a population implosion that is set to detonate in the year 2081 [4]. To many, this may seem far off, but to a demographer, this is an alarming timetable.
The 2-part documentary series points to five big shifts—women’s revolution, economic prosperity, the sexual revolution, the divorce revolution, and radical individualism—as the Infinity Stones on our demographic gauntlet. Together, they have changed the trajectory of humankind.
Women’s education and work opportunities have expanded significantly since WW2 (a real gain), but our institutions never fully adjusted. We told women they could pursue careers while leaving work and childcare organized as if every family still had a full-time caregiver at home. Rational couples respond by delaying children, having fewer, or quietly abandoning the idea altogether. Like Roberta, a 72-year-old educator who looks back on her life with zero regrets. In an interview with Self Magazine, she said that being a school teacher had “kept me in touch with the vitality of young people,” and that was enough for her [5]. Like Roberta, so many find themselves unable or unwilling to prioritize children. Saying no to newborns has become the new norm.
Prosperity has made children more expensive in practice. We pour more time, money, and anxiety into each child. Housing, health care, and education are all growing more costly. In a culture that treats travel, credentials, and personal experiences as non-negotiable, the opportunity cost of a third or fourth child can feel enormous. Reliable contraception and the sexual revolution then shifted the mental default: instead of assuming that marriage will naturally lead to children unless something goes wrong, couples seem to assume no children unless everything is perfect.
Add to this the fragility of marriage and a culture of radical individualism. If you are not sure your relationship will last, or if the highest good is unrestricted personal freedom, committing to raise helpless humans for decades can look less like a blessing and more like an unnecessary risk. Pew Research data from 2024 suggests that over 1/3 of people who report choosing not to have a child list “not wanting to” or “couldn’t afford one” as the deciding factor [6]. To be clear, none of this means that people suddenly hate kids. In survey after survey, many adults say they want more children than they actually end up having. The gap between “desired” and “real” family size is where Demographic Winter really seems to live.
The consequences of not having kids are not just emotional or spiritual; they are economic and political. Aging societies with too few workers struggle to fund pensions and health care. Human capital decreases. Labor shortages bite. Rural towns empty. Institutions built for a growing population—schools, churches, civic organizations—must manage gradual shrinkage and then, in some places, outright collapse. Economist Melissa Kearney, a distinguished Professor of Economics at the University of Notre Dame and a research associate at the National Bureau of Economic Research, asserts that low-fertility rates pose an existential threat to long-term economic growth in the United States. She further argues that, once these trends begin, they are difficult to reverse [7].
At BYU, this conversation cuts close to our own theology and culture. Members of the Church of Jesus Christ of Latter-day Saints talk unapologetically about posterity, eternal families, and covenants that stretch across generations. Yet we live under the same economic pressures and cultural narratives as everyone else. While fertility rates among members of the Church of Jesus Christ remain higher than the U.S. national average, they too are on a steady decline. Data shows that as of 2021-2022, the average U.S. church member had roughly 2.4 to 2.8 children, down from higher rates in the 1980s, reflecting a national trend toward smaller families [8]. So our question is not whether these pressures exist, but whether we will notice them and respond deliberately, or simply drift along until low fertility becomes another unexamined “new normal.”
That response cannot be coercive. We have seen where coercive population policy leads, and it is ugly. But between compulsion and complacency lies a wide field of possible reforms: Economist Melissa Kearney’s work on declining U.S. fertility suggests that there is no single “silver bullet” to reverse depopulation trends. She notes that even very generous child-care subsidies or tax credits only nudge fertility up a few hundredths of a child per woman. The point, she argues, is not to force people to have babies, but to remove structural barriers so that adults who want children can actually have them. That means housing policy that makes it realistic to start families before age 35, reliable and affordable child care, and workplaces that accommodate childbirth [9].
Philip Levine, another second professor of economics at Wellesley College, stresses the need for comprehensive immigration policy and social insurance systems designed for aging societies. In his article “The Causes and Consequences of Declining US Fertility,” co-authored by Dr. Kearney, he suggests that the United States could maintain the working-age population with a sizable increase in immigration, barring a reversal in the fertility decline [10]. But effective immigration policy is easier said than done. Regardless of policy, there are measurable things that any citizen can offer to support parents working toward a family: practical help with child care, less judgment about non-linear career paths, and more visible honor for the quiet heroism of parenting and fostering. BYU itself can ask whether its own housing, employment, and academic expectations line up with the family-first rhetoric we preach.
In Infinity War, the snap feels inevitable. Only later, in the sequel, do we learn that there was still time to assemble a different team and reverse the damage. Demography is less forgiving. There is no time-heist for unborn generations, no five-year jump that brings them back. But we are not yet past the point where our decisions no longer matter. If we take both the data and our commitment to each other and our communities seriously, we can choose policies and personal priorities that make room for the children we say we hope will be there.
