Adverse maternal, fetal, and neonatal outcomes among pregnant women with SARS-CoV-2 infection: a meta-analysis of individual participant data
Despite a growing body of research on the risks of SARS-CoV-2 infection during pregnancy, there is continued controversy given the heterogeneity in the quality and design of published studies.
Methods
We examined ongoing studies in our sequential prospective meta-analysis. We pooled data from individual participants to estimate the absolute and relative risk (RR) of adverse outcomes among pregnant women with SARS-CoV-2 infection, compared with confirmed negative pregnancies. Risk of bias was assessed using a modified Newcastle-Ottawa scale.
Results
We examined 137 studies and included 12 studies in 12 countries with 13,136 pregnant women.
Pregnant women with SARS-CoV-2 infection, compared with uninfected pregnant women, had a significantly increased risk of maternal mortality (10 studies; n = 1490; RR 7.68, 95% CI 1.70 at 34.61); intensive care unit admission (8 studies, n=6660, RR 3.81, 95% CI 2.03 to 7.17); receiving mechanical ventilation (7 studies, n = 4887, RR 15.23, 95% CI 4.32 to 53.71); receiving some form of critical care (7 studies, n = 4735, RR 5.48, 95% CI 2.57 to 11.72); and being diagnosed with pneumonia (6 studies; n=4573; RR 23.46, 95% CI 3.03 to 181.39) and thromboembolic disease (8 studies; n=5146; RR 5.50, 95% CI 1.12 to 27.12).
Newborns born to women with SARS-CoV-2 infection were more likely to be admitted to a neonatal care unit after delivery (7 studies; n=7637; RR 1.86, 95% CI 1.12 to 3.08); having been born premature (7 studies; n=6233; RR 1.71, 95% CI 1.28 to 2.29) or moderately premature (7 studies; n=6071; RR 2.92, 95% CI 1. 88 to 4.54); and being born with low birth weight (12 studies; n=11,930; RR 1.19, 95% CI 1.02 to 1.40). The infection was not related to fetal death. In general, the studies had a low or moderate risk of bias.
Conclusions
This analysis indicates that SARS-CoV-2 infection at any time during pregnancy increases the risk of maternal death, severe maternal morbidity, and neonatal morbidity, but not stillbirth or intrauterine growth restriction. As more data becomes available, we will update these findings based on the published protocol.
Comments
Pregnant women who are infected with the virus that causes COVID-19 face a 7-fold increased risk of dying and a significantly increased risk of being admitted to an intensive care unit or suffering from pneumonia, according to research published in BMJ Global Health . The study also suggests that COVID-19 during pregnancy also increases the risk that the baby will need to be admitted to intensive care.
“This study provides the most comprehensive evidence to date suggesting that COVID-19 is a threat during pregnancy,” said Emily R. Smith, assistant professor of global health at George University’s Milken Institute School of Public Health. Washington and lead author of the study. she, said she. “Our findings underscore the importance of COVID-19 vaccination for all women of childbearing age.”
Despite growing knowledge about the risks of COVID-19 during pregnancy, many women of childbearing age in the United States and other countries remain unvaccinated. In some cases, women are hesitant or refusing to receive the vaccine or booster shot because they do not believe COVID-19 poses a risk to young women or are unsure about the safety of the vaccine during pregnancy. Even some doctors may be hesitant to give the vaccine to a pregnant woman, Smith says, even though it is recommended.
Smith and his colleagues pooled individual patient data from 12 studies conducted in 12 countries, including the United States, involving more than 13,000 pregnant women.
The researchers found that, compared to uninfected pregnant women, pregnant women with COVID-19 infection were at:
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Newborns born to women infected with COVID-19 were almost twice as likely to be admitted to a neonatal intensive care unit after birth. They also had a higher risk of being born prematurely. Premature babies are at high risk for lifelong health problems, including delays in early childhood cognitive development, Smith said.
Despite the very serious health risks, more than 80 countries still do not recommend that all pregnant and breastfeeding women get vaccinated against COVID , Smith says. While the evidence has been difficult to gather in the past, this meta-analysis provides public health officials and the public with clear, consistent and compelling findings, she adds.
“This study shows the risk of contracting COVID-19 for both mother and baby,” Smith said. “All countries, including the United States, must make access to COVID vaccines an urgent priority to save lives and prevent health problems.”
What is already known about the topic
- Despite the growing literature on SARS-CoV-2 infection during pregnancy, it is difficult to synthesize the information and evaluate the overall quality of the evidence given the heterogeneity in study design, selection of comparison groups, methods to assess infection, population-specific baseline risks. and definitions of key results.
- Previous reviews based on published data have included limited data from low-income countries.
What does this study contribute?
- We established plans for a sequential prospective meta-analysis in April 2020 with the goal of better understanding the excess risks, or lack thereof, of COVID-19 during pregnancy.
- This individual patient data meta-analysis of unpublished and published data from a dozen studies includes more than 13,000 pregnant women and shows that COVID-19 during pregnancy increases the risk of maternal mortality, intensive care unit admission , mechanical ventilation, care or being diagnosed with pneumonia or thromboembolic disease.
- Babies born to infected pregnant women were more likely to be admitted to the neonatal intensive care unit and to be born prematurely.
- Unlike other reviews, we found no link between SARS-CoV-2 infection during pregnancy and an increased risk of stillbirth after 28 weeks’ gestation, nor any link with intrauterine growth restriction.
- Additionally, we include the first large pregnancy cohort data set from sub-Saharan Africa.
How it affects clinical practice
- Global guidance has been equivocal about the potential risks of infection and the benefits and safety of vaccination, and more than 80 countries currently do not recommend that all pregnant and breastfeeding women should be vaccinated.
- Given the clear and consistent findings regarding the risk of COVID-19 infection during pregnancy, the global effort to improve access to safe preventive and therapeutic treatments is an urgent priority.
Conclusion Taken together, this analysis of 12 studies including 13,136 pregnant women from 12 countries indicates that SARS-CoV-2 infection at any time during pregnancy increases the risk of maternal mortality, severe maternal morbidity, and adverse outcomes in the newborn. born. These findings underscore the need for global efforts to prevent COVID-19 during pregnancy through targeted delivery of vaccines and non-pharmaceutical interventions. More efforts are needed to advance our understanding of the best management strategies and clinical care for pregnant women infected with SARS-CoV-2 and their newborns. As more data become available, we will update these findings based on the published protocol. |
Video of lead researcher Emily Smith discussing the research here .
The research was supported by grants from the Bill & Melinda Gates Foundation.
