The study of rural-urban gradients in fertility is important for a better understanding of population change in developing countries. Using multiple surveys for 60 developing countries, I test the hypothesis and describe the underlying dynamics of an inverted U-shaped evolution in the rural-urban fertility ratio over time. The results confirm an inverted U-shaped evolution in the rural-urban fertility differential over the course of the national fertility transition. This is mainly driven by the urban-rural lag in the transition onset and, to a lesser extent, by the differential paces of decline. Rural-to-urban migrants also play a role at different stages of the transition. The implications of these results for our understanding of the process of urban population growth and the prospects for future fertility decline in high fertility countries are discussed.
Published in a peer-reviewed journal of the Population Council.