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Meta-Analysis
. 2021 Apr 19;193(16):E540-E548.
doi: 10.1503/cmaj.202604. Epub 2021 Mar 19.

The impact of COVID-19 on pregnancy outcomes: a systematic review and meta-analysis

Shu Qin Wei  1 , Marianne Bilodeau-Bertrand  1 , Shiliang Liu  1 , Nathalie Auger  2
Affiliations
Meta-Analysis

The impact of COVID-19 on pregnancy outcomes: a systematic review and meta-analysis

Shu Qin Wei et al. CMAJ. .

Abstract

Background: The impact of coronavirus disease 2019 (COVID-19) on maternal and newborn health is unclear. We aimed to evaluate the association between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during pregnancy and adverse pregnancy outcomes.

Methods: We conducted a systematic review and meta-analysis of observational studies with comparison data on SARS-CoV-2 infection and severity of COVID-19 during pregnancy. We searched for eligible studies in MEDLINE, Embase, ClinicalTrials.gov, medRxiv and Cochrane databases up to Jan. 29, 2021, using Medical Subject Headings terms and keywords for "severe acute respiratory syndrome coronavirus 2 OR SARS-CoV-2 OR coronavirus disease 2019 OR COVID-19" AND "pregnancy." We evaluated the methodologic quality of all included studies using the Newcastle-Ottawa Scale. Our primary outcomes were preeclampsia and preterm birth. Secondary outcomes included stillbirth, gestational diabetes and other pregnancy outcomes. We calculated summary odds ratios (ORs) or weighted mean differences with 95% confidence intervals (CI) using random-effects meta-analysis.

Results: We included 42 studies involving 438 548 people who were pregnant. Compared with no SARS-CoV-2 infection in pregnancy, COVID-19 was associated with preeclampsia (OR 1.33, 95% CI 1.03 to 1.73), preterm birth (OR 1.82, 95% CI 1.38 to 2.39) and stillbirth (OR 2.11, 95% CI 1.14 to 3.90). Compared with mild COVID-19, severe COVID-19 was strongly associated with preeclampsia (OR 4.16, 95% CI 1.55 to 11.15), preterm birth (OR 4.29, 95% CI 2.41 to 7.63), gestational diabetes (OR 1.99, 95% CI 1.09 to 3.64) and low birth weight (OR 1.89, 95% CI 1.14 to 3.12).

Interpretation: COVID-19 may be associated with increased risks of preeclampsia, preterm birth and other adverse pregnancy outcomes.

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Conflict of interest statement

Competing interests: None declared.

Figures

Figure 1:
Figure 1:
Flow chart for the selection of studies.
Figure 2:
Figure 2:
Forest plots of summary crude odds ratios (ORs) and 95% confidence intervals (CIs) for the association between coronavirus disease 2019 (COVID-19) and preeclampsia. (A) Association between COVID-19 and preeclampsia (patients with COVID-19 versus patients without COVID-19). (B) Association between severe COVID-19 and preeclampsia (patients with severe versus mild COVID-19).
Figure 3:
Figure 3:
Forest plots of summary crude odds ratios (ORs) and 95% confidence intervals (CIs) for the association between coronavirus disease 2019 (COVID-19) and preterm birth. (A) Association between COVID-19 and preterm birth (patients with COVID-19 versus no COVID-19). (B) Association between symptomatic COVID-19 and preterm birth (patients with symptomatic versus asymptomatic COVID-19). (C) Association between severe COVID-19 and preterm birth (patients with severe versus mild COVID-19).
Figure 4:
Figure 4:
Forest plots of summary crude odds ratios (ORs) and 95% confidence intervals (CIs) for the association between coronavirus disease 2019 (COVID-19) and stillbirth.
See this image and copyright information in PMC

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