The CDC’s New Report on COVID-19 and Pregnancy Links Coronavirus Infections to Preterm Births
Here's what expecting moms need to know.
The Morbidity and Mortality Weekly Report, which features data from the COVID-19-Associated Hospitalization Surveillance Network (COVID-NET), looked at 7,895 women ages 15 to 49 hospitalized with COVID-19 across 13 states from March 1 to August 22. From that large pool of data, researchers singled out 598 women—or about one-fourth of the patients—who were pregnant during their COVID-19-related hospital stays. Out of those women, 54.5% showed no symptoms of the illness. The remaining women (45.5%) were symptomatic, and some cases of severe illness occurred—16% were admitted to intensive care units, 8% required mechanical ventilation, and 1% of the patients died from COVID-19.
According to researchers, one important study finding involved COVID-19's impact on preterm births, or births that occur before 37 weeks of pregnancy have been completed. Among 458 women discharged for completed pregnancies—10 of whom suffered a pregnancy loss—445 pregnancies resulted in a live birth, and 12.6% were preterm. Symptomatic women were more likely to deliver preterm (23.1%) compared to 8% of asymptomatic women. The study authors said that the preterm delivery rate (when looking only at live births) was higher for women who were hospitalized for COVID-19 than the same rate observed in the general US population in 2018.
The authors also noted in their findings that COVID-19 seems to disproportionally affect Black and Hispanic pregnant women in the US: 42.5% of the pregnant COVID-positive women were Hispanic, while 26.5% were Black. "Long standing inequities in the social determinants of health, such as occupation and housing circumstances that make physical distancing challenging, have put some racial and ethnic minority groups at increased risk for COVID-19-associated illness and death," the authors of the report wrote, before calling for more research on the topic.
Because 5% of the general population is typically pregnant at any given time, per the study, the overall higher proportion of pregnant women with COVID-19—along with the disease's impact on those women—suggests that COVID-19 may have a disproportionate affect on pregnant women compared to nonpregnant women. But this new research also comes with its fair share of limitations. For one, researchers speculate that the higher number of pregnant women hospitalized with COVID-19 may suggest an overall lower threshold for admitting pregnant women to hospitals for any reason. Pregnant women may also be more likely to receive COVID-19 testing compared to nonpregnant women, researchers say. Additionally, the authors weren't aware of the "reason for hospital admission" for nearly half the women evaluated, which took away the authors' ability to discern between labor and delivery admissions and COVID-19-related admissions.
Nevertheless, this new study tends to line up with previous research on the topic: A review of research on COVID-19, published in March in the Archives of Academic Emergency Medicine, found that “COVID-19 can cause fetal distress, miscarriage, respiratory distress and preterm delivery in pregnant women.”
Additionally, a report published in July in JAMA focused on whether or not COVID-19 infections put women at a higher risk for delivering a baby preterm. The report’s authors looked at deliveries from two different time periods at the same hospital in London. They analyzed births that occurred from October 1, 2019, to January 31, 2020, and those that occurred from February 1, 2020, to June 14, 2020. While the researchers did find that “the incidence of stillbirth was significantly higher during the pandemic period,” they didn’t report a significant difference in number of Cesarean sections, the number of neonatal unit admissions, or the number of births prior to 37 weeks of gestation or after 34 weeks gestation.
While more research still needs to be done, experts seem to agree that pregnant women have an increased risk of severe illness from a COVID-19 infection. For this reason, the CDC recommends limiting your contact with others if you’re pregnant, adding that those you live with might want to consider taking this precaution as well. It's also recommended that pregnant women wear a mask, avoid people who aren’t wearing a mask, stay six feet from anyone outside their household, and skip activities that make social distancing difficult. On top of that, the CDC also recommends testing newborns birthed to mothers with COVID-19 for the coronavirus, and isolating both mothers and newborns with COVID-19 in hospital settings, in order to keep those they come into contact with safe.
The information in this story is accurate as of press time. However, as the situation surrounding COVID-19 continues to evolve, it's possible that some data have changed since publication. While Health is trying to keep our stories as up-to-date as possible, we also encourage readers to stay informed on news and recommendations for their own communities by using the CDC, WHO, and their local public health department as resources.
To get our top stories delivered to your inbox, sign up for the Healthy Living newsletter