The Mystery of the Declining U.S. Birth Rate

The Issue:

Up until the Great Recession, the number of babies born per woman in the United States had been quite stable for the previous three decades. The birth rate fluctuated within a relatively narrow range, often along with economic conditions, with fewer babies born during lean times and with births recovering when economic growth was stronger. However, the U.S. birth rate has fallen precipitously since the 2007 Great Recession, with no signs of reversing. This decline cannot be explained by demographic, economic, or policy changes. It is reflective of lower childbearing rates across successive cohorts.

The U.S. birth rate has fallen by 20% since 2007. This decline cannot be explained by demographic, economic, or policy changes.

The Facts:

• The Great Recession disrupted a stable period in birth rates. For the almost three decades between 1980 and 2007, the U.S. birth rate hovered between 65 and 70 births per 1,000 women between the ages of 15 and 44. The birth rate followed a predictable pro-cyclical pattern, falling during economic downturns and recovering when the economy improves. But something changed around the time of the Great Recession; the birth rate fell precipitously, and it did not recover when the economy improved. Rather, the U.S. birth rate has continued a steady descent. As of 2020, the U.S. birth rate was 55.8 births per 1,000 women between the ages of 15 and 44, a decline of almost 20 percent from the rate of 69.3 in 2007. 
• The decline in births cannot readily be explained by changing population composition. The sustained decline in U.S. births since 2007 has been driven by declining births among many demographic groups, rather than by changes in population composition. Births have fallen among women in their early 20s, late 20s, and teens (in fact, the teen birth rate in the U.S. has been falling steadily since the mid-1990s). Births have fallen among white women, Black women, and Hispanic women, with the largest declines among Hispanic women. Births have also fallen among women with and without college degrees and among both married and unmarried women. The population of U.S. women of childbearing age has actually shifted toward groups that tend to have higher birth rates, not lower birth rates, with the exception of a rising share of women of childbearing age being unmarried. 
• No obvious policy or economic factor can explain much of the decline. The onset of the Great Recession clearly played a role in the early stages of the decline. Beyond that, it is difficult to identify any policy or economic factor that can statistically account for the continued decline. Casual observers have suggested that a variety of potential factors are responsible for the decline, including greater take-up of highly effective contraception, the high cost of raising children, improved occupational opportunities for women, and the high level of student debt carried by young adults. Our research finds little empirical support for these possible explanations. Moreover, none of the measures that have been shown in previous research to have a causal effect on annual birth rates – such as labor market conditions (beyond the Great Recession), certain social policy indicators (such as child support enforcement) or reproductive health policy measures (such as abortion clinic closures) – have changed in ways that can account for the drop in the national birth rate since 2007. 

• Successive generations of women are having fewer children at every age. While the largest decreases in birth rates have occurred amongst women under 30, it is possible that this reflects more than a general tendency among women to delay childbirth and that there are generational changes taking place. Cohorts of U.S. women born after the mid-1980s are having fewer births at all ages. The above figure shows that subsequent cohorts of women who were born in the windows 1968 to 1972, 1973 to 1977, and 1978 to1982 all had similar childbearing age profiles throughout their lives. Then, the cohort of women born between 1983 and 1987 had fewer children throughout their 20s and their 30s. The next two five-year birth cohorts of women (born between 1988 and 1997) have fewer children than earlier cohorts. In other words, later cohorts of mothers have fewer children at every age than women in earlier cohorts. The likelihood of births “catching up” at older ages across these cohorts seems limited.
• Shifting priorities could be the primary driver for the decline in the birth rate since 2007. There is survey and anecdotal data suggesting that perhaps more recent cohorts of young adults have different preferences for having children, aspirations for life, and views about parenting norms that are driving the decline in the U.S. birth rates. These shifts could reflect preferences and norms that changed primarily in earlier decades, long before 2007 – such as more intensive parenting practices and expanded economic opportunities for women – in ways that profoundly shaped the world views of today’s younger adults.
• A sustained decline in the birth rate would have important social and economic consequences. A temporary decline in annual birth rates does not necessarily portend social and economic challenges. However, the decline in annual birth rates in the U.S. has been ongoing for many years and as shown above, corresponds to a decline in the number of children a woman has over her lifetime, on average. This trend predicts a persistently lower fertility rate in the U.S., which, absent increased immigration, would lead to a smaller workforce and an older population. In general, a smaller workforce and an aging population would have negative implications for economic productivity and per capita income growth. In addition, the combination of a smaller workforce and an aging population puts fiscal pressure on social insurance programs, like Social Security, that rely on tax payments from current workers to pay the benefits of current retirees. Some observers point to the idea that, all else equal, a shrinking population will reduce humans’ carbon footprint, and hence have positive environmental effects. We are not aware of any evidence, though, that population declines corresponding to the size of the drop in U.S. fertility would have a meaningful effect on climate outcomes. 
• The onset of the COVID pandemic added another layer of uncertainty to childbearing trends in the United States. Births conceived between the onset of the pandemic in March 2020 and the end of that year fell by around 60,000. This is a smaller drop than many had expected, given the dramatic rise in unemployment and in economic and public health uncertainty at the outset of the pandemic. It is possible that government assistance blunted the economic impact of the pandemic on many families.