Research links COVID-19 during pregnancy to stillbirth
New government data shows that pregnant women infected with COVID-19 face increased chances of stillbirth compared to uninfected women, and this risk has increased fourfold after the emergence of the delta variant.
The Federal Centers for Disease Control and Prevention released a report Friday that examined 1.2 million births in 736 hospitals nationwide from March 2020 through September 2021.
Stillbirths were generally rare, totaling 8,154 among all deliveries. But the researchers found that for women with COVID-19, about one in 80 births resulted in a stillbirth. Among the uninfected, it was 1 in 155.
Among those with COVID-19, stillbirths were more common in people with chronic high blood pressure and other complications, including those in intensive care or on ventilators.
“These findings underscore the importance of COVID-19 prevention strategies, including vaccination before or during pregnancy,” said CDC researcher Carla DeSisto and co-authors.
There is no information on how many have received COVID-19 shots, although the authors note that the US vaccination rate among pregnant women after Delta emerged last summer was 30%.
Pregnant people with COVID-19 are more likely than others to develop severe, even fatal disease, and face an increased risk of preterm labor and other complications. Previous studies on stillbirth and COVID-19 have had mixed results, but the report reinforces concerns among obstetricians and anecdotal data.
While the absolute risk of stillbirth is low, any pregnant woman should not underestimate the risk of COVID-19, said Dr. Mark Trentin, a professor at Baylor College of Medicine in Houston. Help write the American College of Obstetricians and Gynecologists’ recommendations for COVID-19 vaccination during pregnancy.
“The really sad thing is that we had a 10-month vaccine that was very effective and we can’t convince people to take advantage of this,” Torrentin said.
Some experts have speculated that the virus may cause placenta accreta or other abnormalities that could harm the fetus.
Joseph Biggio, who specializes in high-risk pregnancies at Ochsner Health in New Orleans, said the study does not prove that COVID-19 caused stillbirth. He said it was possible that some of the women were so critical that doctors trying to keep them alive “couldn’t intervene on behalf of a fetus they knew was in trouble”.
The researchers relied on medical records, and noted that they were unable to determine whether the COVID-19 diagnoses listed at the time of delivery represented current or past infections.
In general, stillbirths are more common among blacks, those who became pregnant over the age of 35 or those who smoked tobacco during pregnancy.
The study did not include pregnancy outcomes by race, an area the authors said they plan to investigate in future research “because COVID-19 has disproportionately affected many racial and ethnic minority groups, putting them at greater risk of disease and death.”
Follow AP Medical Writer Lindsey Tanner at @LindseyTanner.
The Associated Press’s Department of Health and Science receives support from the Howard Hughes Medical Institute’s Division of Science Education. AP is solely responsible for all content.