ArticleBMC pregnancy and childbirth2021
Associations of COVID-19 lockdown with gestational length and preterm birth in China.
Article in BMC pregnancy and childbirth, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers, 1 of them a synthesis that pooled it.
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Who cites it
12 citing papers in PubMed, 1 synthesis or guideline pooled it, 14 citations in OpenAlex.
- Impacts of COVID-19 pandemic on preterm birth: a systematic review and meta-analysis.Public health · 2022Pooled it
- COVID-19 lockdowns and gestational diabetes risk: trimester-specific exposure and stratified outcomes.BMC pregnancy and childbirth · 2026Article
- Changes in the quantity and quality of births after the COVID-19 pandemic: an interrupted time series analysis of two million births in Southwest China.BMC pregnancy and childbirth · 2026Article
- Association between COVID-19 outbreak and preterm birth rates in a low-infection cohort from a tertiary Shanghai maternity center: a retrospective study.Frontiers in pediatrics · 2026Article
- Seasonal Patterns of Preterm Birth During the COVID-19 Pandemic: A Retrospective Cohort Study in Romania.Medicina (Kaunas, Lithuania) · 2025Article
- COVID-19 lockdowns affected birthing outcomes in a regional New South Wales Health District.The Australian & New Zealand journal of obstetrics & gynaecology · 2024Article
- Associations of COVID-19 lockdown with birth weight in China.Frontiers in pediatrics · 2024Article
- The Temporal Relationship Between the Coronavirus Disease 2019 (COVID-19) Pandemic and Preterm Birth.Obstetrics and gynecology · 2023Observational
- Comparison of adverse pregnancy and birth outcomes using archival medical records before and during the first wave of the COVID-19 pandemic in Kinshasa, Democratic Republic of Congo: a facility-based, retrospective cohort study.BMC pregnancy and childbirth · 2023Article
- Impact of the 1st Wave of the COVID-19 Pandemic and Lockdown on In Utero Transfer Activity in the Paris Area, France.Journal of clinical medicine · 2022Article
- 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.Geburtshilfe und Frauenheilkunde · 2022Article
- High-risk pregnant women's experiences of the receiving prenatal care in COVID-19 pandemic: a qualitative study.BMC pregnancy and childbirth · 2022Article
Corrections and comments
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Authors and funding
25 authors at 13 institutions in 2 countries.
Funding
Abstract
backgroundThe effects of COVID-19 lockdown measures on maternal and fetal health remain unclear. We examined the associations of COVID-19 lockdown with gestational length and preterm birth (PTB) in a Chinese population.
methodsWe obtained medical records of 595,396 singleton live infants born between 2015 and 2020 in 5 cities in Guangdong Province, South China. The exposed group (N = 101,900) included women who experienced the COVID-19 Level I lockdown (1/23-2/24/2020) during pregnancy, while the unexposed group (N = 493,496) included women who were pregnant during the same calendar months in 2015-2019. Cumulative exposure was calculated based on days exposed to different levels of emergency responses with different weighting. Generalized linear regression models were applied to estimate the associations of lockdown exposure with gestational length and risk of PTB (< 37 weeks).
resultsThe exposed group had a shorter mean gestational length than the unexposed group (38.66 vs 38.74 weeks: adjusted β = - 0.06 week [95%CI, - 0.07, - 0.05 week]). The exposed group also had a higher risk of PTB (5.7% vs 5.3%; adjusted OR = 1.08 [95%CI, 1.05, 1.11]). These associations seemed to be stronger when exposure occurred before or during the 23rd gestational week (GW) than during or after the 24th GW. Similarly, higher cumulative lockdown exposure was associated with a shorter gestational length and a higher risk of PTB.
conclusionsThe COVID-19 lockdown measures were associated with a slightly shorter gestational length and a moderately higher risk of PTB. Early and middle pregnancy periods may be a more susceptible exposure window.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.