Research led by a team from the George Washington University Milken Institute School of Public Health found that pregnant women infected with the virus that causes COVID-19 face a seven-time increase in risk of death, as well as a significantly elevated risk of pneumonia infection or admission to an intensive care unit.
The study, published Monday in BMJ Global Health, also suggests that COVID-19 during pregnancy 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 the study’s lead author Emily R. Smith, an assistant professor of global health at Milken Institute SPH. “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 hesitate or refuse to get the vaccine or booster shot because they underestimate the risk of COVID-19 to young women or because they feel unsure about the safety of the vaccine during pregnancy. Some doctors may even hesitate to give the vaccine to a pregnant woman, Smith said.
Smith and her 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:
- Seven times higher risk of dying during pregnancy or childbirth.
- More than three times greater risk of being admitted to the intensive care unit. People with COVID-19 who need ICU care are also more likely to die.
- About 15 times higher risk of needing ventilator treatment. COVID-19 can affect the ability to breathe, and in severe cases patients need mechanical ventilation in order to survive.
- About 23 times higher risk of developing pneumonia, a potentially life-threatening complication of COVID-19.
- More than five times higher risk of thromboembolic disease, or blood clots, that can cause pain, swelling, or other life-threatening complications.
Babies born to women infected with COVID-19 were almost twice as likely to be admitted to a neonatal intensive care unit after birth. They were also at higher risk of being born prematurely. Preterm babies are at high risk of having lifelong health problems including delays in early childhood cognitive development, Smith said.
Despite the very serious health risks, Smith said more than 80 countries still do not recommend that all pregnant and lactating women get the COVID vaccine. She added that while evidence has not always been easy to assemble, this meta-analysis should provide public health officials and the public with clear, consistent and compelling findings.
“This study shows the risk of getting COVID-19 for both mother and baby,” Smith said. “All countries, including the United States, should make access to COVID vaccines an urgent priority in order to save lives and prevent health problems.”
The study, “Adverse maternal, fetal and newborn outcomes among 1942 pregnant women with SARS-CoV-2 infection, as compared to 11194 negative pregnancies: A individual participant data meta-analysis,” was published in the Jan. 16, 2023, issue of BMJ Public Health.
Watch a video of lead researcher Emily Smith discussing the research here.
The research was supported by grant funding from the Bill & Melinda Gates Foundation.