Fertility and Childlessness in the United States
Level 4 - case-series / case-control
Level 4 by non-clinical design analogy (structural economic modeling calibrated on cross-sectional census data).
OpenAlex W1931351567 · doi:10.1257/aer.20120926
What was done
The authors constructed a structural economic model of fertility distinguishing the extensive margin (childlessness) from the intensive margin (number of children per mother). The model's parameters were calibrated using empirical relationships observed in the 1990 US Census regarding education, marriage rates, and fertility patterns across men and women.
What was found
The empirical baseline showed that maternal fertility decreases with education, childlessness follows a U-shaped curve across education levels, and marriage rates are hump-shaped with education for women but strictly increasing for men. Model estimates indicated that 2.5% of women were childless due to poverty and 8.1% due to the high opportunity cost of childrearing. Historical trends in total factor productivity and education drove a U-shaped dynamic in childlessness rates alongside decreasing maternal fertility.
Why it matters
Separating the decision to have any children from family size decisions explains why childlessness can be high among both the lowest- and highest-educated women through distinct economic mechanisms.
Limits
The findings rely on structural economic theory and calibration against 1990 cross-sectional US Census data rather than direct empirical measurement or quasi-experimental variation. Sample sizes, parameter uncertainty, and confidence intervals are not reported in the abstract, and results may not generalize outside the US demographic context.
Cited by
- context The average number of children per mother in the United States is around 2.6.
- contradicts In the United States, the average number of children per mother has increased to approximately 2.4 to 2.6 children.