This paper provides an assessment of the nature and magnitude of Tanzania's
recent fertility decline, using robust methods for the identification of f
ertility trends. A decline in Tanzanian fertility began some time in the la
te 1970s or early 1980s. The pattern of decline exhibits similarities to pa
tterns identified some years ago in Zimbabwe and Kenya. The decline has bee
n especially marked in urban areas. It has been accompanied by a rapid rise
in contraceptive prevalence from the very low levels before 1990 to just u
nder 20 per cent of currently married women of reproductive age. Although f
alling marital fertility associated with a rise in contraceptive use is the
main contributor to the decline in fertility, a rise in the average age at
marriage has also made a (smaller) contribution, as has the AIDS epidemic.
The fact that fertility is declining in Tanzania raises questions about th
e social and economic requirements for fertility transitions to begin in su
b-Saharan Africa.