Catholicism and the Economics of Fertility.

The article examines the effect of Catholicism on fertility in the United States. It is shown that many studies on Catholicism and fertility are seriously flawed because of sample selection bias, which occurs because ex-Catholics prefer smaller families than non-Catholics. It has been found that religious activity has no effect on fertility if it is treated as an endogenous variable. Further, it is shown that the fertility transition in the United States is partly related to the changing effect of Catholic norms. Thus, the direct effect of economic variables, such as women's earnings, on fertility might have been overstated by economists. In this study, wife's schooling is used as a proxy for her earning ability, because the quality of data available on wife's earnings is low, and also because it is not possible to identify the relationship between wife's earnings and fertility with the data at hand. Thirdly, wife's schooling is an important determinant of her earning ability. It might also reduce fertility by increasing her ability to plan family size. It has been shown that current religion is not necessarily independent of fertility decisions. Results indicate that a positive effect of Catholicism on fertility is inflated, when current religious status is used as a measure. The study also explains the divergence between Catholic and non-Catholic fertility that has been claimed to have occurred during the `baby boom' period. This study also shows that the results are affected by whether the husband's or the wife's religion is used in the estimate. The results also indicate that Catholic norms have a highly significant positive effect on fertility for respondents born before 1920. Variations in fertility after this period are at best weakly related to a Catholic upbringing. This implies that changes in fertility over time are at least partly associated with changes in the influence of norms.