Impacts of religion on sex selection in Vietnam

We examine whether religion influences sex-selection behavior under a persistent son preference. Specifically, we investigate whether religion promotes a different sex ratio among children under 5 years of age and whether religiosity has externalities on secular households, using whole-population census data and religious establishments in Vietnam. The results show that the ratio of boys is lower among religious households in both commune fixed effects and the instrumental variable (IV) approach. Furthermore, using the 1955–1974 North–South Vietnam division that reallocated religious communities for another commune-level IV, we find that a higher pious follower ratio leads to a lower ratio of boys in the secular population.