ArticleAmerican journal of obstetrics and gynecology2022
Preterm birth after the introduction of COVID-19 mitigation measures in Norway, Sweden, and Denmark: a registry-based difference-in-differences study.
Article in American journal of obstetrics and gynecology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers, 2 of them syntheses that pooled it.
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Who cites it
21 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- The association of COVID-19 lockdowns with adverse birth and pregnancy outcomes in 28 high-income countries: a systematic review and meta-analysis.Nature human behaviour · 2025Pooled it
- Impacts of COVID-19 pandemic on preterm birth: a systematic review and meta-analysis.Public health · 2022Pooled it
- Preparedness for maternal and offspring health surveillance in pandemics: Lessons learned from studies on COVID-19 using Scandinavian registry data.Acta obstetricia et gynecologica Scandinavica · 2026Article
- COVID-19 and Global Perinatal Health: Lessons Learned on Maternal-Neonatal Outcomes, Infant Feeding Practices, and Health Care Economics across Income Settings.American journal of perinatology · 2026Article
- Bridging Knowledge Gaps in Understanding SARS-CoV-2 Infection During Pregnancy.Paediatric and perinatal epidemiology · 2025Article
- Trends in Preterm Births in Italy and Maternal Risk Factors in 2018-2022-A Registry-Based Study.Children (Basel, Switzerland) · 2025Article
- Impact of pandemic service changes on ethnic inequalities in maternal and perinatal outcomes in England: a population-based study.BMJ open · 2025Article
- Characteristics and Rates of Preterm Births During the COVID-19 Pandemic in Germany.JAMA network open · 2024Article
- Socioeconomic disparities in changes to preterm birth and stillbirth rates during the first year of the COVID-19 pandemic: a study of 21 European countries.European journal of public health · 2024Article
- Changes in stillbirths and child and youth mortality in 2020 and 2021 during the COVID-19 pandemic.International journal of epidemiology · 2024Article
- Impact of COVID-19 on Perinatal Outcomes and Birth Locations in a Large US Metropolitan Area.Healthcare (Basel, Switzerland) · 2024Article
- The Incidence of Necrotizing Enterocolitis and Late-Onset Sepsis during the COVID-19 Pandemic in Sweden: A Population-Based Cohort Study.Neonatology · 2024Article
- The Temporal Relationship Between the Coronavirus Disease 2019 (COVID-19) Pandemic and Preterm Birth.Obstetrics and gynecology · 2023Observational
- Indirect effects of the COVID-19 pandemic on risk of gestational diabetes and factors contributing to increased risk in a multiethnic population: a retrospective cohort study.BMC pregnancy and childbirth · 2023Article
- Preterm birth rates among twins during the Danish COVID-19 lockdown and when restrictions were relaxed.Acta paediatrica (Oslo, Norway : 1992) · 2023Article
- The impact of non-pharmaceutical interventions on premature births during the COVID-19 pandemic: a nationwide observational study in Korea.Frontiers in pediatrics · 2023Article
- Impact of COVID-19 on pregnancy-related healthcare utilisation: a prospective nationwide registry study.BMJ open · 2022Article
- Changes in preterm birth and birthweight during the SARS-CoV-2 pandemic: a nationwide study in South Korea.Scientific reports · 2022Article
- Preterm birth rates were slightly lower in Denmark during the first year of the COVID-19 pandemic compared with the previous 4 years.Acta paediatrica (Oslo, Norway : 1992) · 2022Article
- Increase in preterm stillbirths in association with reduction in iatrogenic preterm births during COVID-19 lockdown in Australia: a multicenter cohort study.American journal of obstetrics and gynecology · 2022Article
Corrections and comments
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Authors and funding
12 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundAlthough some studies have reported a decrease in preterm birth following the start of the COVID-19 pandemic, the findings are inconsistent.
objectiveThis study aimed to compare the incidences of preterm birth before and after the introduction of COVID-19 mitigation measures in Scandinavian countries using robust population-based registry data. STUDY
designThis was a registry-based difference-in-differences study using births from January 2014 through December 2020 in Norway, Sweden, and Denmark. The changes in the preterm birth (<37 weeks) rates before and after the introduction of COVID-19 mitigation measures (set to March 12, 2020) were compared with the changes in preterm birth before and after March 12 from 2014 to 2019. The differences per 1000 births were calculated for 2-, 4-, 8-, 12-, and 16-week intervals before and after March 12. The secondary analyses included medically indicated preterm birth, spontaneous preterm birth, and very preterm (<32 weeks) birth.
resultsA total of 1,519,521 births were included in this study. During the study period, 5.6% of the births were preterm in Norway and Sweden, and 5.7% were preterm in Denmark. There was a seasonal variation in the incidence of preterm birth, with the highest incidence during winter. In all the 3 countries, there was a slight overall decline in preterm births from 2014 to 2020. There was no consistent evidence of a change in the preterm birth rates following the introduction of COVID-19 mitigation measures, with difference-in-differences estimates ranging from 3.7 per 1000 births (95% confidence interval, -3.8 to 11.1) for the first 2 weeks after March 12, 2020, to -1.8 per 1000 births (95% confidence interval, -4.6 to 1.1) in the 16 weeks after March 12, 2020. Similarly, there was no evidence of an impact on medically indicated preterm birth, spontaneous preterm birth, or very preterm birth.
conclusionUsing high-quality national data on births in 3 Scandinavian countries, each of which implemented different approaches to address the pandemic, there was no evidence of a decline in preterm births following the introduction of COVID-19 mitigation measures.
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