Wanted Fertility, Unwanted Fertility, and Fertility Decline: A Fresh Assessment

John B. Casterline, Ohio State University
Jennifer A. Mendoza, Ohio State University
Laila El-Zeini, American University in Cairo

Fertility decline occurs as a result of decline in desired fertility and/or reduction in unwanted births. The relative weight of these two sources of decline is subject to dispute, with direct implications for public policy (in particular, the justification for investment in family planning programs). This paper takes a fresh look at this issue. The contribution is substantive and methodological: (i) The analysis encompasses three decades (roughly 1975-2005), a longer time-span than previous analyses. (ii) Change in fertility is directly examined, rather than inferring change from cross-sectional patterns (as in other past influential analyses). (iii) The analysis uses new methodology for estimating the percentage of births unwanted and wanted/unwanted fertility rates. (iv) A new decomposition of fertility decline into contributions of wanted and unwanted fertility is developed and applied. Patterns by major region and stage of transition are examined. Particular attention is given to prospects for further decline in Africa.