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.

中文翻译：

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低收入和中等收入国家的生育率转变：偏好的作用


自二十世纪中叶以来，南半球国家的生殖行为经历了前所未有的迅速和普遍的变化，大多数低收入和中等收入国家（LMIC）的生育率从转型前的高水平下降到每名妇女生育 3 个孩子以下。随着时间的推移，人们对这些下降原因的主要理论达成了粗略的共识。然而，人们普遍认为，生育偏好的变化（即理想家庭规模的下降和生育限制的需求上升）是生育率转变的主要驱动因素，这一观点仍然存在争议。一些研究质疑这一结论，并认为现有需求的不断增加是中低收入国家生殖革命的主要原因。本研究的目的是协调相互竞争的“需求”和“实施”观点。本文评估了已发表的分解的优点和缺点，这些分解采用了观察到的总生育率和避孕普及率的趋势，并将它们分解为各自的需求和实施部分。这项研究的主要结论是，生育率转变是由偏好及其实施的变化驱动的。声称对需求或实施具有完全主导作用的说法是基于有缺陷的方法，因此必须予以拒绝。