MPIDR Working Paper

Cohort overlays of evolving childbearing patterns: how postponement and recuperation are refl ected in period fertility trends

Frejka, T.
MPIDR Working Paper WP-2010-026, 43 pages.
Rostock, Max Planck Institute for Demographic Research (June 2010)
Revised November 2010; former title: Birth cohort overlays of changing childbearing patterns: a unique proximate fertility determinant with unexpected tempo effects
Open Access


Combining cohort and period perspectives a method is developed that follows the process of childbearing postponement and recuperation and its reflection in total period fertility levels and trends in low fertility populations. It is complementary to methods pioneered by Bongaarts and Feeney (1998) estimating tempo-adjusted period total fertility rates. The method can be characterized as revealing the internal structural mechanism of the postponement and recuperation process. It is applied to analyzing the fertility history of Western countries, Southern Europe, Central and Eastern Europe, and East Asia during the past half century. Our research concludes that period fertility descents and troughs, for instance, “lowest-low” fertility, as well as increases and peaks are a reflection of changing cohort childbearing patterns due to fertility postponement and recuperation combined with overlays of successive birth cohorts. Period fertility troughs occurred in Western countries during the 1980s, in Central and Eastern Europe around 2000.
The Max Planck Institute for Demographic Research (MPIDR) in Rostock is one of the leading demographic research centers in the world. It's part of the Max Planck Society, the internationally renowned German research society.