ArticleThe Lancet. Digital health2022
The effect of maternal SARS-CoV-2 infection timing on birth outcomes: a retrospective multicentre cohort study.
Article in The Lancet. Digital health, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 76 papers, 2 of them syntheses that pooled it.
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Who cites it
76 citing papers in PubMed, 2 syntheses or guidelines pooled it, 112 citations in OpenAlex.
- The impact of COVID-19 infections on pregnancy outcomes in women.BMC pregnancy and childbirth · 2024Pooled it
- Outcomes of SARS-CoV-2 infection in early pregnancy-A systematic review and meta-analysis.Acta obstetricia et gynecologica Scandinavica · 2024Pooled it
- Background incidence rates and observed-to-expected ratios of adverse events of special interest after covid-19 mRNA vaccination during pregnancy in France: a nationwide population-based study.The Lancet regional health. Europe · 2026Article
- SARS-CoV-2 infection during the first trimester leads to profound immune dysregulation at the maternal-fetal interface despite limited virus detection in placental tissues.Nature communications · 2026Article
- Effectiveness of 2023-2024 Coronavirus Disease 2019 (COVID-19) Vaccines in Pregnant Women.Obstetrics and gynecology · 2026Article
- Stillbirths in Colombia before and during the COVID-19 pandemic: analysis by geographic location and health insurance.BMC public health · 2026Article
- Trimester of maternal SARS-CoV-2 infection differentially predicts newborn size in the COVID-19 Mother Baby Outcomes (COMBO) cohort.Pediatric research · 2026Article
- Association of Area Deprivation Index with perinatal and COVID-19 outcomes during the early pandemic: a secondary analysis of a prospective cohort study.The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians · 2025Article
- Severe acute respiratory syndrome coronavirus 2 and preterm birth, clinical implications-A register-based cohort study from Sweden.Pregnancy (Hoboken, N.J.) · 2025Article
- Impact of COVID-19 Control Measures on Birth Outcomes in Ho Chi Minh City, Vietnam.Journal of preventive medicine and public health = Yebang Uihakhoe chi · 2025Article
- Machine Learning Models to Predict Risk of Maternal Morbidity and Mortality From Electronic Medical Record Data: Scoping Review.Journal of medical Internet research · 2025Article
- Adverse pregnancy and infant outcomes by COVID-19 infection status before and during pregnancy.Pregnancy (Hoboken, N.J.) · 2025Article
- Alterations in Semen Quality and Immune-Related Factors in Men with Infertility who Recovered from COVID-19.MedComm · 2025Article
- The pregnancy outcomes of women with SARS-CoV-2 infection in the first trimester ---a longitudinal cohort study.BMC pregnancy and childbirth · 2025Article
- Impact of maternal COVID-19 infection on offspring immunity and maternal-fetal outcomes at different pregnancy stages: a cohort study.BMC pregnancy and childbirth · 2025Observational
- Infection with SARS-CoV-2 during the first trimester did not adversely impact perinatal and obstetric outcomes subsequent to in vitro fertilization with frozen embryo transfer: a retrospective cohort study.Journal of assisted reproduction and genetics · 2025Article
- Observational
- Prevalence and determinants of adverse pregnancy outcomes among teenage mothers in the Limbe Health District of Cameroon.The Pan African medical journal · 2025Article
- Association ofViruses · 2024Article
- COVID-19 diagnosis, vaccination during pregnancy, and adverse pregnancy outcomes of 865,654 women in England and Wales: a population-based cohort study.The Lancet regional health. Europe · 2024Article
16 more citing papers are in PubMed but not listed here.
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Authors and funding
7 authors at 1 institution in 1 country.
Funding
Abstract
backgroundThe impact of maternal SARS-CoV-2 infection remains unclear. In this study, we evaluated the risk of maternal SARS-CoV-2 infection on birth outcomes and how this is modulated by the pregnancy trimester in which the infection occurs. We also developed models to predict gestational age at delivery for people following a SARS-CoV-2 infection during pregnancy.
methodsWe did a retrospective cohort study of the impact of maternal SARS-CoV-2 infection on birth outcomes. We used clinical data from Providence St Joseph Health electronic health records for pregnant people who delivered in the USA at the Providence, Swedish, or Kadlec sites in Alaska, California, Montana, Oregon, or Washington. The SARS-CoV-2 positive cohort included people who had a positive SARS-CoV-2 PCR-based test during pregnancy, subdivided by trimester of infection. No one in this cohort had been vaccinated for COVID-19 at time of infection. The SARS-CoV-2 negative cohort were people with at least one negative SARS-CoV-2 PCR-based test and no positive tests during pregnancy. Cohorts were matched on common covariates impacting birth outcomes, and univariate and multivariate analysis were done to investigate risk factors and predict outcomes. The primary outcome was gestational age at delivery with annotation of preterm birth classification. We trained multiple supervised learning models on 24 features of the SARS-CoV-2 positive cohort to evaluate performance and feature importance for each model and discuss the impact of SARS-CoV-2 infection on gestational age at delivery.
findingsBetween March 5, 2020, and July 4, 2021, 73 666 pregnant people delivered, 18 335 of whom had at least one SARS-CoV-2 test during pregnancy before Feb 14, 2021. We observed 882 people infected with SARS-CoV-2 during their pregnancy (first trimester n=85; second trimester n=226; and third trimester n=571) and 19 769 people who have never tested positive for SARS-CoV-2 and received at least one negative SARS-CoV-2 test during their pregnancy. SARS-CoV-2 infection indicated an increased risk of preterm delivery (p<0·05) and stillbirth (p<0·05), accounted for primarily by first and second trimester SARS-CoV-2 infections. Gestational age at SARS-CoV-2 infection was correlated with gestational age at delivery (p<0·01) and had the greatest impact on predicting gestational age at delivery. The people in this study had mild or moderate SARS-CoV-2 infections and acute COVID-19 severity was not correlated with gestational age at delivery (p=0·31).
interpretationThese results suggest that pregnant people would benefit from increased monitoring and enhanced prenatal care after first or second trimester SARS-CoV-2 infection, regardless of acute COVID-19 severity.
fundingUS National Institutes of Health.
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