Department of Population, Family and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, NY, USA.
Paediatr Perinat Epidemiol. 2022 Jul;36(4):485-489. doi: 10.1111/ppe.12811. Epub 2021 Sep 13.
Preliminary studies suggest that the SARS-CoV-2 pandemic and associated social, economic and clinical disruptions have affected pregnancy decision-making and outcomes. Whilst a few US-based studies have examined regional changes in birth outcomes during the pandemic's first months, much remains unknown of how the pandemic impacted perinatal health indicators at the national-level throughout 2020, including during the 'second wave' of infections that occurred later in the year.
To describe changes in monthly rates of perinatal health indicators during the 2020 pandemic for the entire US.
For the years 2015 to 2020, we obtained national monthly rates (per 100 births) for four perinatal indicators: preterm (<37 weeks' gestation), early preterm (<34 weeks' gestation), late preterm (34-36 weeks' gestation) and caesarean delivery. We used an interrupted time-series approach to compare the outcomes observed after the pandemic began (March 2020) to those expected had the pandemic not occurred for March through December of 2020.
Observed rates of preterm birth fell below expectation across several months of the 2020 pandemic. These declines were largest in magnitude in early and late 2020, with a 5%-6% relative difference between observed and expected occurring in March and November. For example, in March 2020, the observed preterm birth rate of 9.8 per 100 live births fell below the 95% prediction interval (PI) of the rate predicted from history, which was 10.5 preterm births per 100 live births (95% PI 10.2, 10.7). We detected no changes from expectation in the rate of caesarean deliveries.
Our findings provide nationwide evidence of unexpected reductions in preterm delivery during the 2020 SARS-CoV-2 pandemic in the US. Observed declines below expectation were differed by both timing of delivery and birth month, suggesting that several mechanisms, which require further study, may explain these patterns.
初步研究表明，SARS-CoV-2 大流行以及相关的社会、经济和临床干扰影响了妊娠决策和结果。虽然有一些基于美国的研究检查了大流行头几个月期间出生结果的区域变化，但对于大流行如何在 2020 年全年影响围产期健康指标，包括当年晚些时候发生的感染“第二波”期间，仍有许多未知之处。
描述整个美国 2020 年大流行期间围产期健康指标的月度变化。
对于 2015 年至 2020 年，我们获得了四项围产期指标（每 100 例活产）的全国月度率（每 100 例活产）：早产（<37 周妊娠）、早期早产（<34 周妊娠）、晚期早产（34-36 周妊娠）和剖宫产。我们使用中断时间序列方法将大流行开始后（2020 年 3 月）观察到的结果与如果大流行未发生则预期的结果进行比较，这些结果预计在 2020 年 3 月至 12 月期间出现。
在 2020 年大流行的几个月中，观察到的早产率低于预期。这些下降在 2020 年早期和晚期最大，观察到的与预期的差异在 3 月和 11 月之间为 5%-6%。例如，在 2020 年 3 月，观察到的每 100 例活产中 9.8 例早产率低于从历史上预测的每 100 例活产中 10.5 例早产的 95%预测区间（PI）（95% PI 10.2，10.7）。我们没有发现剖宫产率有任何预期变化。
我们的发现提供了全美范围内的证据，证明美国 2020 年 SARS-CoV-2 大流行期间早产率意外下降。观察到的下降低于预期，这与分娩时间和分娩月份都有关，这表明有几种机制（需要进一步研究）可能解释了这些模式。
