The past four decades have witnessed an enormous increase in modern contraception in most low- and middle-income countries. We examine the extent to which this change can be attributed to changes in fertility preferences versus fuller implementation of fertility preferences, a distinction at the heart of intense debates about the returns to investments in family planning services. We analyze national survey data from five major survey programs: World Fertility Surveys, Demographic Health Surveys, Reproductive Health Surveys, Pan-Arab Project for Child Development or Family Health, and Multiple Indicator Cluster Surveys. We perform regression decomposition of change between successive surveys in 59 countries (330 decompositions in total). Change in preferences accounts for little of the change: less than 10 percent in a basic decomposition and about 15 percent under a more elaborate specification. This is a powerful empirical refutation of the view that contraceptive change has been driven principally by reductions in demand for children. We show that this outcome is not surprising given that the distribution of women according to fertility preferences is surprisingly stable over time.

中文翻译：

---

低收入和中等收入国家的生育偏好和避孕变化

在过去的四十年里，现代避孕措施在大多数低收入和中等收入国家有了巨大的增长。我们研究了这种变化在多大程度上可归因于生育偏好的变化与生育偏好的更全面实施，这是关于计划生育服务投资回报的激烈辩论的核心区别。我们分析了来自五个主要调查项目的国家调查数据：世界生育率调查、人口健康调查、生殖健康调查、泛阿拉伯儿童发展或家庭健康项目以及多指标类集调查。我们对 59 个国家的连续调查之间的变化进行回归分解（总共 330 次分解）。偏好的变化对变化的影响很小：在基本分解中不到 10%，在更详细的规范中大约为 15%。这是对以下观点的有力实证反驳，即避孕措施的改变主要是由对儿童的需求减少推动的。我们表明，鉴于根据生育偏好的女性分布随着时间的推移出奇地稳定，因此这一结果并不令人惊讶。