Spatial Variation in the Educational Gradient of First Motherhood in Spain: Occurrence and Timing.

Several studies have analyzed the relationship between educational attainment and fertility across countries, identifying significant differences. However, these works often overlook intra-country variation, which may play an important role in moderating that relationship. This study examines the heterogeneity in the educational gradient of fertility across Spain, a context characterized by lowest-low and latest-late fertility. Using data from the 2011 Spanish census, we reconstruct the reproductive history of 656,248 women aged 25-50, of whom 403,140 had become mothers. This large sample allows to analyze the educational gradient in first motherhood across Spanish provinces. To do so, we apply mixture cure models, which enable us to differentiate between the occurrence and the timing of the transition. The results reveal substantial regional variability in the educational gradient for both dimensions, although the association between the gradients in occurrence and timing is weak across space. We further find that cross-province variation in the educational gradient in the timing of the transition is largely driven by the heterogeneous behavior of non-university educated women, a pattern not observed for occurrence. Finally, we identify a negative association between the educational gradient and the province's GDP per capita, particularly strong for the timing of the transition.