An Analysis of Fertility Differentials in Developing Countries

Fertility differentials are analyzed by using two stage least squares and data from developing countries for the period 1968-70. Results confirmed that adult literacy rates levels of childrens education and female labor force participation rates were negatively related to fertility. However life expectancy at birth (up to approximately 50 years) was positively related to fertility and only thereafter were life expectancy at birth and fertility negatively related. Although a negative relationship was found between family planning programs and fertility this result must be interpreted cautiously because of the absence in most countries included in the sample of family planning programs in 1968. In general fertility was relatively insensitive to socioeconomic conditions during the early stages of economic development. Rising life expectancy at birth and falling female labor force participation tended to increase fertility thus partially offsetting the negative effect on fertility of increases in adult literacy rates and school enrollment rates and decreases in the importance of agricultural employment. Fertility only becomes sensitive to socieconomic conditions in the later stages of economic development. In reaching these results the author used an approximation of gross reproduction rate a fertility measure that is independent of population-age distribution and estimated relationships in the context of a simultaneous equations model thereby eliminating some of the simultaneous equations bias that is inherent in ordinary least squares estimates.