“Husband’s Income, Wife’s Income, and Number of Biological Children in the U.S.”, 2022-02-21 ():
[previous: 2021] Previous studies have found that the positive relationship between personal income and fertility for men in the United States is primarily due to childlessness among low-income men. Yet because of the opposite effects of income on fertility for men and women, it is important to examine the effects of income net of spouse’s income.
An analysis of income from all sources and biological fertility data for husbands and wives from the Survey of Income and Program Participation (2014) shows that for men their own income is positively associated with the number of their biological children, while their spouse’s income is negatively associated with total children ever fathered. The reverse is true for women.
These results are not because of childlessness among low-income men and high-income women, but also hold true among all those with children. For men and women aged 45–65, who likely have completed fertility, these results hold regardless of whether or not education is controlled.
These findings suggest that if status is measured as personal income for men and husband’s income for women, the positive relationship between status and fertility persists in a post-demographic transition society.
…When this data was collected, the United States was a society characterized by low fertility, high educational homogamy (2005) and where more than half of all married couple families had 2 breadwinners (U.S. Bureau of Labor Statistics 2017). Yet these results suggest that men with high incomes with a spouse with a low income have the most biological children in the United States, while women with low incomes with a spouse who earns a high income have the most biological children. For women there is no doubt reverse causation given tradeoffs between childbearing and raising and income earning. Nevertheless, the results support theorizing from behavioral ecology about the positive effect of an important dimension of social status—personal income—on reproductive success for men in the United States. For women, the results suggest an age-old form of female status—marriage to a high status man—is positively associated with reproductive success for women in the contemporary United States. Thus the central problem of modern sociobiology (1986) may be more a problem of appropriately measuring social status for men and women in modern societies, rather than a change to behavior that is no longer adaptive.