Background: In recent years, fertility rates have declined substantially in most Latin American countries. Uruguay has been at the forefront of this regional process, as the country’s total fertility rate plummeted from 2 children per woman in 2015 to 1.37 in 2021 (and continued to drop to 1.28 in 2022, according to preliminary data). Objective: We decompose fertility decline by age and birth order in Uruguay, and identify the probable mechanisms (e.g., postponement, stopping) behind this decline. Methods: Combining census data and vital statistics, we estimate period fertility rates by age and conditional period fertility rates by birth order and age. We also decompose the relative contribution of decline in each age and birth order to total decline in TFR. Results: Our findings suggest that the postponement of births, especially among adolescent and very young women, was the main driver of the big fertility decline. Additionally, the fall in higher-order births, mostly among middle-aged women, played a significant role in the overall decline. The findings also reveal an increase of nearly two years in age at first birth between 2016 and 2021. Conclusions: This unprecedented decline in fertility appears to be leveling off. Moreover, we expect that some of the births by adolescents and young women that were avoided during the big fertility decline will take place at some point in the future, probably generating a slight rebound in the total fertility rate. Contribution: Our paper is the first to identify the demographic mechanisms leading to lowest-low fertility in Uruguay. It also contributes to discussions on the impact of the current adolescent fertility decline in short- and medium-term fertility trends.

中文翻译：

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大幅下降：乌拉圭最低-低生育率（2016-2021 年）（作者：Wanda Cabella、Ignacio Pardo、Gabriela Pedetti、Mariana Fernández Soto）

背景：近年来，大多数拉丁美洲国家的生育率大幅下降。乌拉圭一直走在这一区域进程的前列，该国的总生育率从2015年每名妇女生育2个孩子骤降至2021年的1.37（根据初步数据，到2022年继续下降至1.28）。目的：我们按年龄和出生顺序对乌拉圭的生育率下降进行分解，并确定这种下降背后的可能机制（例如，推迟、停止）。方法：结合人口普查数据和人口动态统计，我们估计按年龄划分的经期生育率和按出生顺序和年龄划分的有条件经期生育率。我们还分解了每个年龄和出生顺序的下降对总生育率下降的相对贡献。结果：我们的研究结果表明，推迟生育，尤其是青少年和非常年轻的女性，是生育率大幅下降的主要驱动因素。此外，高位生育率的下降（主要是中年女性）在总体下降中发挥了重要作用。研究结果还显示，2016 年至 2021 年间，第一胎出生的年龄增加了近两岁。 结论：这种前所未有的生育率下降似乎正在趋于平稳。此外，我们预计，在生育率大幅下降期间避免的一些青少年和年轻女性的生育将在未来某个时候发生，这可能会导致总生育率略有反弹。贡献：我们的论文是第一篇确定导致乌拉圭生育率最低的人口机制的论文。它还有助于讨论当前青少年生育率下降对短期和中期生育趋势的影响。