The publication contains detailed information on the evolution of fertility behaviours, changes in the forming and breaking up of couples and the importance of immigration. The research was led by Dr. Daniel Devolder, from the Centre for Demographic Studies, on Idescat's request.
The study reveals that, in terms of first births, 23% of native women of fertility age haven't had any children up until the reference date of this survey (1 November 2007). This absence of fertility is partly due to the fact that native women have their first child at a later age—older than 30. Similarly, it is worth pointing out the relation between the age of female immigrants when they arrive and their adaptation to the fertility patterns of Catalan women. The fertility patterns of women who migrated to Catalonia from abroad before the age of 13 are the most similar to those of native Catalan women.
The complete chart detailing the aforementioned results, from the Demographic Survey 2007, can be found via Statistical queries by territory.