The aim of this paper is to analyse the determinants of the first union formation and, then, the factors that determine the probability of Spanish women having their first, second or third child, for a set of Spanish-born females between 1961 and 1980. We use the Fertility, Family and Values Survey of 2006, conducted by the Sociological Research Centre in 2006. The multivariate technique deployed consists in different discrete-time duration models that enable control for unobserved heterogeneity. The results show, among other things, that highly educated women and women from more recent cohorts are more likely to delay the first union and the first maternity. However, once their first child has been born, educational attainment does not seem to make a big difference in successive parities.

Key words: cohabitation, maternity, education.
JEL Classification: J12, J13.