Contracting COVID-19 while pregnant can have deadly consequences for the mother, a new study published today in American Journal of Obstetrics and Gynecology shows.
The study, which followed 240 pregnant women in Washington state between March and June 2020, found that COVID-19 mortality among them was significantly higher than in similarly aged individuals with COVID-19 who were not pregnant.
Specifically the study found:
- Pregnant women with COVID-19 had a 3.5 times higher rate of associated hospitalization than the similarly aged people who had COVID-19 and were not pregnant.
- The mortality rate was 13 times higher among pregnant mothers than among similarly aged individuals infected with COVID-19 who were not pregnant. This said, most of the pregnant patients with COVID-19 had asymptomatic or mild infections and healthy pregnancies.
- The three women who died of COVID-19 were from minority ethnic groups and had other health conditions such as obesity and hypertension.
Of the 240 pregnant women with SARS-CoV-2 infections, 24 were hospitalized and three succumbed to the virus. Dr. Kristina Adams Waldorf, an obstetrician-gynecologist with the University of Washington School of Medicine and the paper's senior authory, said these data suggest a severe underreporting of mortality related to COVID-19 among mothers in the United States.
"The mortality rate was shockingly high," Adams Waldorf said. "We were very surprised by this."
The three maternal deaths in the study cohort represent 6.7% of all maternal deaths associated with COVID-19 counted in the entire United States through mid-October, although annual births at the collaborating sites make up only 1.4% of annual births nationally, she said.
"We are gravely concerned that COVID-19-associated maternal deaths have been massively undercounted nationally and that the impact on pregnant patients, particularly with underlying conditions is greater than currently underappreciated," she added. The date was compiled by a Washington state collaborative that included 35 large hospitals and clinic systems. They perform 61% of the 86,000 annual childbirth deliveries. The Washington State COVID-19 in Pregnancy Collaborative was led by Adams Waldorf and Erica Lokken, a UW epidemiologist.
The study made several comparisons between the clinical course of COVID-19 and Influenza A virus H1N1 2009.
Unlike the influenza A virus H1N1 2009 pandemic, when pregnant women were quickly identified in the United States as a high-risk and vulnerable group, pregnancy was not identified as a high-risk condition for COVID-19 disease or mortality for the first, critical eight months of the pandemic, the report noted.
Overall, the study findings indicate that pregnant patients are at risk for severe or critical disease or mortality compared with non-pregnant adults, as well as for preterm birth, the report concludes.
"The idea that pregnant patients were protected from COVID-19 is a myth," Adams Waldorf said.
Use of this data in the report is important, she noted, because it can guide public health workers and physicians in their mitigation of COVID-19 among vulnerable populations. Pregnant healthcare workers are receiving the COVID-19 vaccine. But as of Jan. 27, 2021, most pregnant individuals are not included in the groups prioritized to receive vaccinations now.
"Our data indicates that pregnant people did not avoid the pandemic as we hoped that they would and communities of color bore the greatest burden," Adams Waldorf said. She urges pregnant women to discuss the risks and benefits of COVID-19 vaccination with their prenatal care provider.
"These results suggest that the exclusion of pregnant patients from COVID-19 vaccine trials was a mistake," said Adams Waldorf. "Here is an important group that is typically highly vulnerable to influenza infections and, yet they were excluded from COVID-19 vaccine trials. Pregnant patients should have been given the option to enroll in vaccine trials so that we would better understand vaccine risks and benefits to them."
Adams Waldorf added that although the community may be experiencing COVID-19 fatigue this is no time to let our collective guard down, especially with the new variants present within our communities.
"We still need to be really careful about how large our bubble is within our families, to be very careful about handwashing and mask use, and to do everything that we can until enough of the population is vaccinated that we have herd immunity in the U.S., " she said.
This work was supported primarily by funding from the University of Washington Population Health Initiative, Department of Obstetrics & Gynecology and philanthropic gift funds.
This work was also supported by the National Institute of Allergy and Infectious Diseases (AI133976, AI145890, AI143265, HD098713, HD001264, AI120793) and by the National Institute of General Medical Sciences (T32 GM008244). Study data were managed using a REDCap electronic data capture tool hosted by the Institute of Translational Health Sciences at the University of Washington, which was supported by the National Center for Advancing Translational Sciences (UL1TR002319).
The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or other funders. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
