Theories of Fertility

Economic theories of fertility assume that parents have the number of children they do because they desire approximately that number , given the cost of birth control. This demand for children at a household level, is affected by many socio-economic factors such as the level of human capital of family members, family income and assists and the experience on the child mortality.

Demographic Transition Theory

Demographic transition theory describes how populations change from balanced regimes of high fertility/high mortality to regimes of low fertility/low mortality (Davis 1945; Notestein 19290. Aside from it's modeling of three phases of demographic change, which has strong heuristic appeal, prepositional statements articulating casual mechanisms have come somewhat haphazardly in the theory's development. Notestein.s (1945) original formulation assumed that mortality decline is quickly achieved during modernization, but fertility reduction lags behind owing to traditional ponytails social norms and structures, resulting in a transitional stage characterized by rapid population growth. As irrational ponytails norms and social structures erode under the onslaught of industrialism, urbanization, individualism, fertility equilibrates with mortality to form a balanced, low-growth demographic regime. This early emphasis on social psychological change was quickly overshadowed by a more policy relevant rational choice focus (szreter 1993) that requires individual - or household-level analysis. For example, Davis's (1963) theory of change and response asserts that mortality reduction is the quintessential harbinger of the demographic transition: When faced will improved child survival, households must choose between having more children or upward social mobility. according to Davis, mobility usually wins. likewise, Becker's (1960, 1988) new household economics, Caldwell's (1982). wealth-flows, and easterly (Easterlin and Crimmins 1985) supply-and-demand approach all attitude macro social demographic change to the microeconomics of utility maximization. Given the broad influence of Davis's (1963) dictum that macro level explanations of fertility behavior must link to micro-processes (i.e., methodological individualism), the literature has been dominated by search for micro level and proximate determinants of fertility behavior . This rational choice revisionism has adumbrated demographic transition theory's early emphasis on the macro social determination of fertility. The theory has been weighed down with supplementary arguments drawn from different disciplines , leaving only a hollow core proposing that ...socioeconomic development will lead to natality decline ... sometime after a major decline in mortality. (Beaver 1975:9). As a result , demographic transition theory's explanation for fertility decline , which is indistinguishable from that of modernization theory because of its emphasis on , generalized modernization (i.e. industrialization, urbanization , affluence and education ) (Chesnais 1992:356; Simmons 1988:92), has progressed very little over the years . In response , challenges to the historical and contemporary relevance and accuracy of this demographic modernization theory have mounted(Crenshaw 1989). For instance , results from the Princeton European Fertility Project suggest that socioeconomic forces played no role in fertility behavior prior to Europe's demographic transitions , that changes in mortality were not pivotal in those transitions , and that the pace and timing of the fertility decline were driven primarily by tastes and access to contraceptive technology (Knodel and van de Walle 1986). Others question demographic transition theory's applicability to contemporary Third World countries . Results from the World Fertility Survey question socioeconomic theories of fertility behavior , apparently falsifying the notion that wage workers or women in modern sectors experience lower fertility than they're more tradition counterparts ( Cleland and wilson 1987). These authors and others conclude that education, secularization, cultural diffusion provide ch3ecks on fertility (Lesthaeghe and Wilson 1986), while other relegate social structure to a channeling- role that mediates the spread of ideas, attitudes, and information regarding fertility norms and practices (Bongaarts and Watkins 1996). Theoretical and methodological ambiguities and anomalies have taken their toll on demographic transition theory, leading some researchers to conclude that demographic transition theory is near death. (Hirschman 1994:2 13. although many midrange theoretical propositions and empirical generalizations have been offered to answer various critiques of transition theory, they provide neither a more parsimonious nor a more compelling general model of demographic regimes.

Economic Versus Ideation Theories of Fertility

Although the final conclusion of the Princeton fertility study has been recently challenged in at least one country and attributed to incomplete data faulty modeling (Galloway et al., 1994), it still stands out in the form of a negative sweeping generalization: a significant fraction of the total decline of fertility in Northern and western Europe during the eiod 1870-1930 was not due to measurable social and economic transformations, as the conventional demographic transition theory would have it. The observation that fertility levels as well as the pace of decline tend to cluster along regional, ethnic and language boundaries prompted the inference that changes were driven by a diffusion mechanism whereby regional, cultural and language barriers could sometimes offer resistance to a wave of change or, vice versa, precipitate further changes. Whilst the idea that diffusion may drive the process of fertility decline is quite reasonable and attractive, it was never well formulated, that is, the mechanisms through which diffusion was supposed to operate were never spelled out with precision. Further, testing of this weakened version of the hypothesis was rarely done directly and instead proceeded via a residual test, e.g., what could not be explained by measurable ("structural") factors most be attributable to diffusion. In the aftermath of Princeton fertility study the field experienced the fierce and rigid opposition between two explanatory frameworks. One reduced fertility behavior to the out some of rational decision making by individuals seeking to maximize some type of utility. Although in its most rigorous form, this framework was introduced in demography as a direct import from economics, a much loose form had already been applied by demographers ( the demographic transition theory is a good example). and was also present in formulations apparently very distanced from the utility maximization framework (Caldwell's intergenerational flows is an illustration of this). the other framework, a much more loosely respondent to influences from cultural factors and adherence to practices and beliefs characteristic of ethnic, language or other groups to which actors belong. Waves of ideational change originating in a particular social context could sometimes ( and under conditions that usually remain opaque) invade-other social context and, if adopted, could go a long way toward explaining the demise of a high fertility regime. An example of this is the idea that 'westernization' is at the root of fertility changes in some developing areas. Nowhere is the contrast between these two frameworks these two frameworks more starkly formulated than in Cleland and Wilson's rendition ( Cleland and Wilson, 1987). IN this review the authors describe the differences between the frameworks and mount an attack on the economic explanation showing that all the available evidence regarding fertility decline in developing areas point to the existence of influences associated with ideational factors that far outweigh those associated with individual socioeconomic positions. Whether this is the case or not is not as fundamental as the resolution of two key theoretical issues. First, is it reasonable to retify these two frameworks as if there truly competing entities in zero-sum game? Second, can we conceive of diffusion or ideational processes where a new behavior is adopted without incorporating constraints imposed by individual's socioeconomic positions? In my own perception the answer to both is negative. I will deal with each of them in reverse order.