The fertility of recent migrants to England and Wales: interrelationships between migration and birth timing

摘要

Estimates of fertility for the overseas-born based on the period Total Fertility Rate (TFR) suggest that levels of childbearing are significantly higher among foreign-born women than women born in the UK. However, the inter-relationship between migration and subsequent family formation means that aggregate measures of fertility based on period TFRs may not be a useful indicator of the likely completed family size that migrant women will have at the end of their reproductive lives. The aim of this paper is to quantify levels of childbearing in the period before and after migration and hence to examine the inter-relationship between the migration event and the timing of childbearing, and whether this relationship differs by country of birth. Data from the Office for National Statistics Longitudinal Study, a 1% sample of the England and Wales population, are used to identify the reported date of arrival in the UK and to estimate childbearing prior to, and subsequent from, arrival in England and Wales. The data show that migrant groups experience low fertility rates prior to arrival (especially those arriving at young ages). Fertility rates peak in the first one to four years subsequent to arrival, especially for migrants from lower income countries. Migrants from high income countries show a delay in fertility after migration to England and Wales, and lower fertility rates, as compared to those from low income countries. We speculate that our finding of differing fertility profiles by country of birth groupings are likely to relate to the reason for migrating. Higher fertility rates for migrants from lower income countries may relate to family-related migration, whereas lower fertility among migrants originating in higher income countries may be due to employment related moves.