The distortion of fertility due to migration: A comparative analysis of migrants in the Netherlands and stayers in Poland

Background: Several studies have shown that migrants from Central and Eastern Europe to Western Europe experience an increase in fertility after migration. The literature on migrants’ childbearing patterns offers several explanations for this phenomenon. Objective: This study examines the childbearing of Polish women who migrated to the Netherlands, comparing their fertility to that of non-mobile Polish women. Methods: Using the Families of Poles in the Netherlands (FPN) survey and the Generations and Gender Survey (GGS) for Poland, we calculate the Total Fertility Rate (TFR) and average number of children for Polish female migrants in the Netherlands by cohort, socio-demographic characteristics and declared migration objective. Results: The TFR for Polish migrants, standardised according to the sending population distribution by age, education, partnership status and region of origin, was 1.02. Before and in the year of migration, their TFR was 0.87. Already in the first year after migration, the TFR increased to 1.76 and remained elevated, especially for family migrants, but declined considerably in the fourth year after migration. Conclusions: Controlling for observable socio-demographic differences between migrants and the sending population does not explain the differences in fertility. Family migrants experienced an increase in fertility after migration, suggesting an interrelation between mobility and childbearing timing. Women declaring other reasons for migration experienced a smaller and less sustained increase in fertility. Childbearing patterns were most distorted for those who migrated during peak childbearing years. Contribution: For Polish women in the Netherlands, periodic fertility measures are inflated due to tempo distortions in the early years after migration, which conceals different childbearing patterns for different types of migration.