Limited Effects of SARS-CoV-2 Pandemic-related Lockdowns and Reduced Population Mobility on Preterm Birth Rates: A Secondary Analysis of Bavarian Obstetric Quality Parameters from 2010 to 2020

Changes in the rate of preterm infants during the COVID-19 pandemic Lockdown Period-data from a large tertiary German University Center

PURPOSE

After living with the COVID-19 pandemic for more than 2 years, the impact of lockdown measures on preterm birth rates is inconsistent according to data from different countries. In this study, rates of preterm-born infants during the time of COVID-19-related lockdowns were analyzed in a tertiary perinatal center at Munich University, Germany.

METHODS

We analyzed the number of preterm births, infants, and stillbirths before 37 weeks of gestation during the German COVID-19 lockdown period compared to the same time periods in the years 2018 and 2019 combined. Additionally, we expanded the analysis to Pre- and Post-Lockdown Periods in 2020 compared to the respective control periods in the years 2018 and 2019.

RESULTS

Our database shows a reduction in the rate of preterm infants during the COVID-19 lockdown period (18.6%) compared to the combined control periods in 2018 and 2019 (23.2%, p = 0.027). This was mainly based on a reduced rate of preterm multiples during the lockdown period (12.8% vs. 28.9%, p = 0.003) followed by a reversed effect showing a threefold rise in multiple births after the lockdown. In singletons, the rate of preterm births was not reduced during the lockdown. The rate of stillbirths was not affected by the lockdown measures as compared to the control period (0.9% vs. 0.7%, p = 0.750).

CONCLUSION

During the COVID-19 pandemic lockdown period, we found a reduced rate of preterm-born infants compared to a combined control period in the years 2018 and 2019 in our large tertiary University Center in Germany. Due to the predominant reduction in preterm multiples, we postulate that less physical activity might have led to the protective effect by lockdown measures.

Increasing Preterm Delivery and Small for Gestational Age Trends in South Carolina during the COVID-19 Pandemic

Preterm delivery (PTD) complications are a major cause of childhood morbidity and mortality. We aimed to assess trends in PTD and small for gestational age (SGA) and whether trends varied between race-ethnic groups in South Carolina (SC). We utilized 2015-2021 SC vital records linked to hospitalization and emergency department records. PTD was defined as clinically estimated gestation less than (<) 37 weeks (wks.) with subgroup analyses of PTD < 34 wks. and < 28 wks. SGA was defined as infants weighing below the 10th percentile for gestational age. This retrospective study included 338,532 (243,010 before the COVID-19 pandemic and 95,522 during the pandemic) live singleton births of gestational age ≥ 20 wks. born to 260,276 mothers in SC. Generalized estimating equations and a change-point during the first quarter of 2020 helped to assess trends. In unadjusted analyses, pre-pandemic PTD showed an increasing trend that continued during the pandemic (relative risk (RR) = 1.04, 95% CI: 1.02-1.06). PTD < 34 wks. rose during the pandemic (RR = 1.07, 95% CI: 1.02-1.12) with a significant change in the slope. Trends in SGA varied by race and ethnicity, increasing only in Hispanics (RR = 1.02, 95% CI: 1.00-1.04) before the pandemic. Our study reveals an increasing prevalence of PTD and a rise in PTD < 34 wks. during the pandemic, as well as an increasing prevalence of SGA in Hispanics during the study period.

Multiple Gestation as a Risk Factor for SARS-CoV-2-Associated Adverse Maternal Outcome: Data From the COVID-19 Related Obstetric and Neonatal Outcome Study (CRONOS)

Introduction

Studies have shown that pregnant women with COVID-19 have a higher risk of intensive care unit admission and invasive mechanical ventilation support than non-pregnant women. Pregnancy-associated physiological changes in respiratory function may contribute to the elevated risk. Alteration in lung volumes and capacities are attributed to the mechanical impediment caused by the growing fetus. Multiple pregnancies may therefore compromise functional lung capacity earlier than singleton pregnancies and contribute to severe respiratory symptoms of COVID-19.

Materials and Methods

A total of 5514 women with a symptomatic SARS-CoV-2 infection during pregnancy registered in the COVID-19 Related Obstetric and Neonatal Outcome Study were included. The COVID-19-related adverse maternal outcomes were compared in 165 multiple versus 5349 singleton pregnancies. Combined adverse maternal outcome was defined as presence of COVID-19-related hospitalization and/or pneumonia and/or oxygen administration and/or transfer to ICU and/or death. Multivariate logistic regression was used to estimate the odds ratios and 95% confidence intervals were calculated.

Results

The frequency of dyspnea, likelihood of developing dyspnea in a defined pregnancy week and duration of the symptomatic phase of the COVID-19 infection did not differ between the two groups. On average, COVID-19-related combined adverse outcome occurred earlier during pregnancy in women expecting more than one child than in singleton pregnancies. The overall incidence of singular and combined COVID-19-associated adverse maternal outcomes was not significantly different between groups. However, regression analysis revealed that multiple gestation, preconceptional BMI > 30 kg/m 2 and gestational age correlated significantly with an increased risk of combined adverse maternal outcome. Conversely, maternal age and medically assisted reproduction were not significant risk factors for combined adverse maternal outcome.

Conclusion

Our data show that multiple gestation alone is a risk factor for COVID-19-associated combined adverse maternal outcome. Moreover, severe courses of COVID-19 in women expecting more than one child are observed earlier in pregnancy than in singleton pregnancies.

Lack of evidence for effects of lockdowns on stillbirth rates during the SARS-CoV-2 pandemic in Bavaria: analysis of the Bavarian perinatal survey from 2010 to 2020

BACKGROUND

Internationally, potential effects of national SARS-CoV-2-related lockdowns on stillbirth rates have been reported, but data for Germany, including risk factors for fetal pregnancy outcome, are lacking. The aim of this study is to compare the stillbirth rates during the two first lockdown periods in 2020 with previous years from 2010 to 2019 in a large Bavarian cohort.

METHODS

This study is a secondary analysis of the Bavarian perinatal data from 2010 to 2020, including 349,245 births. Univariate and multivariable regression analyses were performed to investigate the effect of two Bavarian lockdowns on the stillbirth rate in 2020 compared to the corresponding periods from 2010 to 2019.

RESULTS

During the first lockdown, the stillbirth rate was significantly higher compared to the reference period (4.04 vs. 3.03 stillbirths per 1000 births; P = 0.03). After adjustment for seasonal and long-term trends, this effect can no longer be observed (P = 0.2). During the second lockdown, the stillbirth rate did not differ in univariate (3.46 vs. 2.93 stillbirths per 1000 births; P = 0.22) as well as in multivariable analyses (P = 0.68), compared to the years 2010 to 2019.

CONCLUSION

After adjustment for known long-term effects, in this study we did not find evidence that the two Bavarian lockdowns had an effect on the rate of stillbirths.

Fewer Preterm Births in the First COVID-19 Pandemic Year? An Evaluation of the Berlin Perinatal Data for the Years 2017 to 2020

Introduction The study analyzes and interprets possible effects of the COVID-19 pandemic on the preterm birth rate. Research questions included: were there fewer preterm births in Berlin in 2020, the first year of the pandemic, compared to the three years before the pandemic? Were there differences in preterm birth rates grouped according to weeks of gestation? Method The perinatal data of all singleton pregnancies were evaluated with regard to birth rates in Berlin, and the numbers of preterm neonates born in the three pre-pandemic years from 2017 to 2019 were compared to the rate for 2020, the first year of the pandemic. Results The overall number of singleton pregnancies born in maternity hospitals and labor wards in Berlin decreased in the first year of the pandemic. The percentage of preterm neonates born before 37 + 0 weeks of gestation (GW) was significantly lower in 2020 compared to the three previous years, with significantly more preterm neonates born before 28 + 0 GW and significantly fewer preterm neonates born between 28 + 0 to 35 + 0 GW. In 2020, significantly fewer neonates born before 37 + 0 weeks of gestation were delivered by primary caesarean section. The incidence of induced births was approximately the same. Conclusions In the first year of the pandemic, a range of social, iatrogenic, and biological factors may have had an impact on preterm birth rates. A Germany-wide evaluation of perinatal data across different German federal states for the period 2020 to 2022 would offer the opportunity to identify the causes of this lower rate of preterm births and determine whether conclusions can be drawn from this which would affect future strategies to reduce preterm birth rates.