U-shaped Association between Education and Fertility among Married Women: Evidence from Japan

Contrary to conventional views, evidence from several countries shows that fertility does not always decline with women’s education due to the recent marketization of childcare, which may enable a positive relationship between women’s labor supply and childcare. Using the most recent individual-level data, this study provides the first evidence of a U-shaped relationship between education and fertility among married Japanese women, focusing on the period 2015-2020, during which market-based childcare expanded substantially in Japan. Compared to low-educated women, highly educated women exhibit both higher fertility and greater labor supply. In contrast, medium-educated women supply more labor than low-educated women but exhibit lower fertility. Unlike the U-shaped education–fertility pattern observed in the United States, labor supply continues to substantially reduce fertility among highly educated women in Japan, as well as among women with medium and low levels of education. Based on standard economic theory of fertility, the U-shaped association could be driven by differences in the relative sizes of the income and substitution effects across education groups. In addition, the U-shaped pattern is not observed for permanent immigrant women living in Japan; instead, their fertility increases with education, likely reflecting a slower pace of economic and social integration. Overall, the results suggest that policies promoting women’s human capital development may enhance both their fertility and labor supply in Japan, while obstacles for women balancing work and child-rearing still exist broadly in the country and more serious attention should be employed in tackling this issue.