Income and Fertility in Couples: New Evidence from Longitudinal Tax Data in Tuscany

This study adopts a dyadic approach to examine whether higher-income women experience lower fertility due to opportunity costs and traditional norms or whether resource pooling within couples facilitates parenthood. We test the gendered relationship between income and fertility in Italy, a stronghold of traditional family roles. Leveraging long-term longitudinal tax data (2003–2021; n = 5,384,425 person-years) from Tuscany—an average Italian region regarding economic development and gender equality—we apply discrete-time event-history analyses. Results show that higher earnings for both men and women increase the likelihood of first birth, with homogamous top-earner couples being the most likely and low-income couples the least. These findings challenge traditional sex-specialisation models and support the view that couples’ income pooling is a parenthood prerequisite. The steep income-fertility link raises concerns about the increasing economic stratification of parenthood across European countries.