Marital fertility decline in developing countries: theories and the evidence.
Using World Fertility Survey (WFS) data, this chapter reviews the decline in marital fertility in developing countries. Classic demographic transition theory holds that modernization reduces fertility because children are no longer perceived as sources of labor and old age security but as economic burdens. Another major theory holds that fertility is high because the strength of the extended family is essential to its members. Other explanations of the fertilty transition include the shift from fatalistic to active thinking and the diffusion of innovations theory. WFS data show a dramatic rise in most countries in contraceptive practice and a consequent fall in marital fertility. Some contries--notably sub-Saharan Africa, North Yemen, north Sudan, Bangladesh, Nepal, and Pakistan--show negligible contraceptive use. An examination of age pattern of marital fertility for declining fertility at older ages in these countries reveals proportionately greater numbers of sons than would normally be expected in Nepal and Pakistan and avoidance of fertility by women who have fertile offspring in Nepal. WFS data confirms there is no thr4eshold level of modernization that produces fertility decline. Urban and educated groups use contraception before other groups. Fertility may rise initially due to the erosion of customs like prolonged lactation and postpartum abstinence. Marital fertility decline, once started, is remarkable for its speed. Socioeconomic factors affect only the timing of fertility decline across groups but not the prosess. A strong correlation exists between education and fertility. which varies across countries but tends to be stronger than economic factors and suggests a carsal relationship between education and fertility. Links between female employment and fertility are more inconclusive, partly because work status can change over a lifetime, while education usually remains the same. To conclude: 1) birth control is absent in many traditional societies but, once accepted, diffuses rapidly wihtin a society regardless of economic status, 2) shifts in family economic structure are not necessary for fertility decline, and 3) fertility change does not depend exclusively on women's stated family size preferences.