Effects of infant mortality, family planning and socioeconomic factors on fertility reduction in developing countries.

The demographic transition theory that mortality reduction is followed by fertility reduction is challenged by reports that many developing countries are trapped in the stage of high fertility and lower mortality. We examined the extent to which reduced infant mortality lowers fertility both directly and indirectly relative to other determinants of fertility in developing countries. According to the available information, determinants of fertility were selected. Data from the United Nations on fertility and its determinants in 117 developing countries were analyzed. Remarkable fertility reduction started only when the infant mortality rate was reduced to a certain "threshold" level around 50-125 per 1000 live births. Fertility reduction is related to the level of infant mortality and other socioeconomic variables mainly indirectly through the increase in contraceptive prevalence. Thus, the demographic transition theory is still maintained. Even in the country group which was "trapped" in the stage of "low" mortality of around 125 and high fertility, fertility reduction seems to be possible by further reducing the infant mortality rate, e.g. to lower than 100, which helps increase family planning practices.