Fertility Transitions in Low‐ and Middle‐Income Countries: The Role of Preferences

Abstract Since the mid‐twentieth century, the Global South has experienced unprecedently rapid and pervasive changes in reproductive behavior with fertility declining from high pre‐transitional levels to below 3 births per woman in most low‐ and middle‐income countries (LMICs). Over time a rough consensus has been reached on major theories about the causes of these declines. However, a controversy remains about the widely held view that changing reproductive preferences (i.e., declining desired family size and rising demand for birth limitation) are the dominant drivers of fertility transitions. Several studies question this conclusion and suggest instead that the rising implementation of existing demand is the main cause of the reproductive revolution in LMICs. The objective of this study is to reconcile the competing “demand” and “implementation” perspectives. This paper assesses the strengths and weaknesses of published decompositions which take trends in the observed total fertility and contraceptive prevalence and break them down into their respective demand and implementation components. The main conclusion from this exercise is that fertility transitions are driven by changes in both preferences and their implementation. Claims of a completely dominant role for either demand or implementation are based on flawed methods and hence must be rejected.