Marital fertility and assortative mating before, during, and after the baby boom in Belgium

Eli Nomes, Katholieke Universiteit Leuven
Jan Van Bavel, Katholieke Universiteit Leuven

Over the course of the 20th century, the expansion of female participation in education and the gradual re-entrance of women into the labour market changed the dynamics of union formation and fertility. After the Baby Boom period, the association between wealth or social status on the one hand and fertility on the other was turned around. In the meantime, educational attainment became a key determinant of fertility. In this paper we investigate the relation between educational assortative mating and marital fertility. We focus on the fertility trends during the Baby Boom and subsequent Baby Bust, which have been shown to be related to changes in marriage patterns. More particularly, we investigate how changes in the timing and quantum of marital fertility were related to the changing combination of his and her educational attainment. We adopt a couple-oriented approach and use retrospective Belgian census data with rich information on educational attainment and marriage and childbearing histories, which allows us to use event history analysis to analyse fertility of the relevant birth cohorts. Results show that couples where both partners are poorly educated experienced the highest fertility among most of the Baby Boom producing birth cohorts. Hypergamous couples (husband more educated than wife) were not far behind, and their fertility levels even exceeded the levels of the low-educated couples among some birth cohorts. High-educated homogamous couples had slightly lower fertility than hypergamous couples. Hypogamy (husband less educated than wife) was clearly associated with lower fertility, even among the younger cohorts. The increasing prevalence of hypogamy during the Baby Bust could thus be one factor contributing to the fertility decline.