Birth intervals, postponement, and fertility decline in Africa: a new type of transition?

We investigated birth-interval dynamics in 24 African countries using data from 76 Demographic and Health Surveys conducted since 1986. Controlling for selection bias in the birth-history data using the Brass-Juárez method and regression models produced almost identical results. Birth intervals have lengthened in every country examined. This analysis uncovered a distinctive and previously undocumented pattern of childbearing that is prevalent across sub-Saharan Africa. After allowing for time trends in birth-interval length, the lengthening of birth intervals in almost every country varies little by women's age or parity. Moreover, in several countries, birth intervals are now too long to be explicable by birth spacing contingent on the age of women's youngest child. Rather, women are postponing births for other reasons. These findings offer empirical support for the idea that the fertility transition in sub-Saharan Africa is following a different pattern from that observed elsewhere.