Returns on investment in human capital of female caregivers: a comparison between Mexico and Spain

This article investigates how education, work experience, gender, and caregiving responsibilities shape wage disparities in Spain and Mexico. Using nationally representative survey data, we estimate Mincer-type wage equations and address sample selection with Heckman’s two-step procedure. Results confirm that education and experience raise wages but with non-linear and context-specific returns. Persistent gender wage gaps are observed: in Mexico, women earn 34–41% less than men, compared to 19–22% in Spain. Caregiving responsibilities—measured as weekly hours of unpaid care in Spain and job absences in Mexico—generate additional wage penalties, particularly for women, and significantly reduce the wage premium of higher education. Cross-country comparability is constrained by measurement differences (firm tenure vs. potential experience; hours vs. absences of care) and by limited exclusion restrictions in the Heckman model, but patterns consistently show that unpaid care undermines women’s returns to human capital. Institutional arrangements condition the size of these penalties: Spain’s stronger welfare and care infrastructure attenuates them, whereas Mexico’s residual, family-based system amplifies them. The study contributes to the literature by documenting the care penalty from a comparative perspective and by highlighting how unpaid care compresses the economic returns to women’s education and work experience.