Reproductive inequality in sub-Saharan Africa: differentials versus concentration

Within developing countries, our understanding of reproductive inequality-how fertility is distributed within a population-has been shaped largely by studies of fertility differentials, a practical but partial-information measure. In this study, we examine whether exclusive reliance on differentials biases this understanding. Findings based on recent data from sub-Saharan Africa show bias. We find that historical and especially cross-country comparisons can yield substantially different conclusions about the magnitude and even the direction of inequality patterns and trends, depending on whether differentials or fuller-information measures are used. For instance, the fertility differentials associated with education have remained relatively stable as national fertility has fallen, but inequality (as calculated by a fuller measure) has increased. Such results underscore the value of complementing existing studies of fertility differentials with analyses based on fuller-information measures. The analyses also show how change in differential fertility behavior and in the educational composition of national populations has shaped recent variations in reproductive inequality in the region.