On the U.S. Total Fertility Rate (TFR) map of 2008, Utah clearly stands out. At the time, the state’s TFR was 2.60, well above the national average of 2.08. Utah’s relatively high birth rate has usually been linked to the demographic dominance of members of the Church of Jesus Christ of Latter-day Saints (LDS), colloquially called the Mormon Church. As of 2020, Mormons constituted a little over 60 percent of the population of Utah. Significantly, second-place Idaho, with a TFR of 2.47 in 2008, also has a large LDS population, roughly a quarter of the population. As noted by demographer Tim Heaton in 1988, when the U.S. fertility rate was plummeting in the 1970s, that of Utah was increasing.
The Mormon church has long encouraged large families. My own paternal grandmother came from an LDS polygamous family of 19 children, born of two sister wives. (As a result, she had quite a few half siblings who were also cousins.) Although I was not raised in the church, I did attend extended-family reunions, where my relatives seemed countless. One year, my first cousins and I got in a fight with another group of boys who turned out to be second cousins attending the same event, held in a large public park. The adults who broke up the scuffle found it quite amusing.
Although the Mormon fertility rate in the U.S. remains higher than average, it has declined considerably in recent years. An article entitled “The Incredible Shrinking Mormon American Family” notes that the TFR of the faith declined from 3.31 in 1981, when the national rate was 1.81, to 2.42 in 2014. Although recent information is not readily available, it seems safe to assume that the decline has continued. The TFR of Utah in 2022 waS 1.85, only a little above the national average.
According to the author of the “Incredible Shrinking Mormon American Family,” changes in church teachings are largely responsible for this decline. As the author notes:
Gradually in the 1980s and ′90s, Latter-day Saint leaders stopped overtly preaching against birth control, even though they still promoted the importance of children. In the 1998 Handbook, contraception is considered to be a matter between the couple and the Lord, and church members are advised not to judge one another about it. (As if.) That don’t-ask-don’t-tell approach has effectively been the church’s policy for the past 20 years.
I am somewhat skeptical of this argument. The prohibition on contraception in the Roman Catholic Church, after all, has not changed, yet the American Catholic fertility rate dropped before that of the Mormons. It is quite possible, however, that LDS families are more inclined to follow church teachings than Catholic ones.
Tim Heaton argued in 1988 that the Mormon family of the time was quite distinctive from the modal American family, being characterized by what he referred to as the “Four C’s,” namely (premarital) chastity, conjugality, children, and chauvinism (the final term referring to a belief in traditional gender roles). But he also argued that these distinctive attributes were changing and would probably continue to do so. As Heaton perceptive argued:
The ideology of the LDS church has been remarkably flexible in accommodating social change The same central doctrine of eternal marriage was used to sanction polygamy in the nineteenth century as is currently used to promote the family patterns described above. As the church has spread to more culturally diverse areas and as new social trends have been adopted by the LDS membership, policies and practices have modified accordingly.
Another possible reason for the declining LDS fertility rate is the gradual convergence of Mormon social and cultural practices with those of the American population at large. Distinctive religious groups in the U.S. that have maintained high or ultra-high fertility rates – the Amish, Old-Order Mennonites, Hutterites, and Haredi Jews – have, in contrast, remained far more distinctive, and their ideologies have not been “remarkably flexible in accommodating social change.”
But purely material factors may also play a role. Housing prices are now elevated in Utah (see the map below), making it difficult for many young couples to have children. Perhaps not coincidentally, in the states with the highest current fertility rates, South Dakota and Nebraska, housing remains much more affordable. But housing prices are even lower in West Virginia, and its TFR is roughly that of the national average. The situation is, to say the least, complicated.
