Some of the largest fertility differences inside rich countries appear not between benefit systems but between communities living under the same national government. Where marriage, worship, schooling, work, kinship, and family norms point in roughly the same direction, large families can remain ordinary. These communities are not policy models or controlled experiments. They are evidence about possible magnitude and about how many institutions may have to align before the difference becomes large.
Israel is the national exception usually offered first. In the 2022 national series, its total fertility rate was near three children per woman while most other wealthy countries were well below replacement. The national average hides the argument, however. Israel contains several demographic worlds living beside one another; a national period TFR is not the same measure as completed fertility or population growth.
Several worlds in one frame A Haredi father and child at the Western Wall in Jerusalem, May 1, 2011, with Israeli soldiers nearby. The same child allowances surround groups with very different family sizes. via Wikimedia Commons
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Israeli data separated by religious observance put Haredi fertility around 6.5 children per woman in the 2020–2022 period, religious Jewish fertility near four, and secular Jewish fertility near two. Muslim fertility, once much higher, had fallen toward three in the reported 2020–2022 period. Even the secular Jewish figure remains high beside most secular populations in Europe or East Asia. These are subgroup period measures, not a single causal estimate for Israel.
Walk through the difference at family scale and the candidate mechanisms become easier to see. A Haredi young adult may grow up surrounded by siblings, cousins, weddings, babies, religious schools, and adults whose lives make early marriage and a large household look ordinary. The same national health system and child allowances reach a secular household living inside a different picture of adulthood.
Haredi fertility has declined from its early-2000s peak. The Israel Democracy Institute reports a fall from about 7.5 in 2003–2005 to 6.5 in 2021–2023. That is an observed trend, not a forecast or a settled explanation. A decline of one birth per woman would be a demographic crisis in many countries; in 2021–2023 it still left Haredi period fertility several times the level found in much of Europe.
A coherent but costly ecology
The Amish provide a striking American case, not a controlled comparison. A 2025 study in Demographic Research used American Community Survey samples from 2000–2021 and the CAPED-2010s Amish population registry to estimate fertility. The two data constructions converged on a period total fertility rate just above six, with births concentrated in the twenties and very little childbearing outside marriage. The estimate is conditioned by membership, retention, age structure, and the authors’ data construction; it is not a national policy effect.
An ecology, not a subsidy Amish children on the way to school, 2006. No single payment produces a fertility rate near six. Young people encounter a dense marriage market, visible family work, and households surrounded by other large households. via Wikimedia Commons
A child walks to school past households containing several other children. Work, worship, courtship, and kinship overlap. Young people do not have to imagine what a family of five children looks like because they ate dinner in one last night. Geographic concentration keeps grandparents and cousins close; churches set expectations and supply practical help; the sacrifice of another child is interpreted among people making a similar sacrifice. Early marriage, birth spacing, and retention help describe the mechanism, but none alone identifies a transferable cause.
This is not an idyll. Communities with strong boundaries can impose severe costs on people who doubt, leave, or do not fit. Formal freedom to exit can coexist with the loss of family, work, language, and nearly every familiar relationship. Selection matters too: the people who remain are partly those able and willing to live within the community’s demands. Fertility measured among members therefore reflects retention as well as formation.
The burdens inside the community are not evenly distributed. Women undergo pregnancy and often perform more care, with possible interruptions to education and paid work; men may face strong duties of provision, religious study, or conformity. Disability, household income, education, and access to outside employment vary within and between the Haredi and Amish cases. A high number alone cannot tell us whether obligations are shared justly or whether dissent is treated humanely.
The Latter-day Saint experience shows that such an advantage can narrow. Church members still tend to have more children than the American average, but Utah no longer sits at the old distance from the rest of the country. In October 2025, church president Dallin H. Oaks publicly said birth rates among members had fallen significantly. The statement establishes leadership concern, not the size or cause of the change; independent demographic evidence is needed before assigning either. Delayed marriage, expensive housing, professional life, and surrounding norms can enter a religious culture rather than stopping at its boundary.
The surviving exceptions carry their force through a pattern observed over years and generations, not through one payment. Worship gives family a meaning. Schools and courtship can help young adults find spouses who share it. Mutual aid makes some costs bearable, while honor makes them intelligible. Earlier marriage preserves time for several births. Selection, retention, material circumstances, internal diversity, and limits on exit are part of the pattern too.
Governments can fund selected components—leave, housing, child allowances, transport, or care—but these observations do not identify a detachable, scalable causal package. Copying a payment does not reproduce membership, kinship, belief, retention, or the social meaning of family; copying boundaries or pressure would raise a different question about coercion.
A demanding community entered and sustained through membership has claims on its members that a tax office does not. Even there, pressure and support can be difficult to separate. The state reaches coercion much sooner because citizens cannot ordinarily leave it without leaving their country.
The examples show that a period fertility estimate above six can coexist with modern medicine and life inside a wealthy nation. They demonstrate magnitude, not authorization. They do not identify a detachable cause or a package public officials can reproduce. They leave a harder lesson: family size can differ greatly when an entire social world is organized around marriage and children, and the same coherence that supplies support can give a community formidable power over its members. The state can offer support; it cannot treat a selected community’s formation or retention as permission to assign spouses, compel pregnancy, or punish exit.
Citations
- Israel Central Bureau of Statistics, Fertility of Jewish and Other Women in Israel, by Level of Religiosity, 1979–2022, 2023.
- Jewish People Policy Institute, “Fertility Rates by Religion and Religiosity in Israel”, 2023.
- Israel Democracy Institute, Statistical Report on Ultra-Orthodox Society in Israel 2024, 2024.
- Lyman Stone, Cory Anderson, and Stephanie Thiehoff, “Amish fertility in the United States”, Demographic Research 52, art. 26 (2025): 869–886.
- Dallin H. Oaks, “The Family-Centered Gospel of Jesus Christ”, October 2025.