BACKGROUND: During the COVID-19 pandemic, birth rates in most higher-income countries first briefly declined and then shortly recovered, showing no common trends afterwards until early 2022, when they unexpectedly dropped. STUDY FOCUS: We analyse monthly changes in total fertility rates in higher-income countries during the COVID-19 pandemic, with a special focus on 2022, when birth rates declined in most countries. We consider three broader sets of explanatory factors: economic uncertainty, policy interventions restricting mobility and social activities outside the home, and the role of vaccination programmes. STUDY DESIGN, DATA: This study uses population-wide data on monthly total fertility rates adjusted for seasonality and calendar effects provided in the Human Fertility Database (HFD, 2023). Births taking place between November 2020 and October 2022 correspond to conceptions occurring between February 2020 and January 2022, i.e., after the onset of the pandemic but prior to the Russian invasion of Ukraine. The data cover 26 countries, including 21 countries in Europe, the United States, Canada, Israel, Japan and the Republic of Korea. METHODS: First, we provide a descriptive analysis of the monthly changes in the total fertility rate (TFR). Second, we estimate the effects of the explanatory factors on the observed fertility swings using linear fixed effects (within) regression models. MAIN RESULTS: We find that birth trends during the COVID-19 pandemic were associated with economic uncertainty, as measured by increased inflation, the stringency of pandemic policy interventions, and the progression of the COVID-19 vaccination campaign, whereas unemployment did not show any link to fertility during the pandemic. LIMITATIONS, REASONS FOR CAUTION: Our research is restricted to higher-income countries with relatively strong social support policies provided by the government as well as wide access to modern contraception. Our data do not allow analysing fertility trends by key characteristics, such as age, birth order and social status. WIDER IMPLICATIONS OF THE FINDINGS: This is the first multi-country study of the drivers of birth trends in a later phase of the COVID-19 pandemic. In the past, periods following epidemics and health crises were typically associated with a recovery in fertility. In contrast, our results show that the gradual phasing out of pandemic containment measures, allowing increased mobility and a return to more normal work and social life, contributed to declining birth rates in most countries. In addition, our analysis indicates that some women avoided pregnancy during the initial vaccination roll-out.

The authors have declared no competing interest.

This study did not receive any funding.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study used (or will use) ONLY openly available human data that were originally located at the Human Fertility Database (https://www.humanfertility.org), OECD website (https://oecd.org), Our World in Data (https://ourworldindata.org) and the Oxford Covid-19 Government Response Tracker (OxCGRT) at GitHub (https://github.com/OxCGRT/covid-policy-dataset)

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All data produced are available online at different online databases: Human Fertility Database (https://www.humanfertility.org), OECD website (https://oecd.org), Our World in Data (https://ourworldindata.org) and the Oxford Covid-19 Government Response Tracker (OxCGRT) at GitHub (https://github.com/OxCGRT/covid-policy-dataset)