Aug. 11, 2021 -- Pregnant women who contract COVID-19 face significantly higher risks for complications, including preterm birth, according to a new study of births in California during the second half of 2020.
The risk of “very preterm” birth -- or less than 32 weeks of gestation -- was 60% higher for those infected with the coronavirus during pregnancy. The risk of preterm birth -- or less than 37 weeks of gestation -- was 40% higher.
“The risk is very real,” Laura Jelliffe-Pawlowski, PhD, senior author of the study and a researcher at the California Preterm Birth Initiative at the University of California at San Francisco, told the San Francisco Chronicle.
“It means you and your baby may start your relationship in the world by being in the hospital much longer than expected,” she said.
In the largest analysis of its kind so far, researchers looked at the association between COVID-19 and preterm delivery for more than 240,000 births documented in California between July 2020 and January 2021. For about 9,000 of them, or 3.7%, there was a positive COVID-19 test during pregnancy.
The preterm birth rate was 11.8% among those who contracted the coronavirus, compared with 8.7% among those who weren’t infected. A COVID-19 diagnosis was linked to a higher risk of “very preterm” birth, preterm birth, and early term birth -- all before 39 weeks of gestation.
Those who contracted the coronavirus were also more likely to have a preterm birth if they had other conditions such as hypertension, diabetes, and obesity. In such cases, the risk of “very preterm” delivery increased 160%, and the risk of preterm delivery increased 100%.
“Considering increased circulation of COVID-19 variants, preventive measures, including vaccination, should be prioritized for birthing persons,” the researchers wrote.
Overall, coronavirus diagnoses on birth certificates increased for all groups during that time, though COVID-19 disparities for communities of color were apparent during pregnancy as well. COVID-19 rates were highest for Native Americans, Native Hawaiians, Pacific Islanders, and Latinas.
“We need to be agile and be able to talk about the multiple ways we can protect women,” Jelliffe-Pawlowski told the newspaper.
“We need to talk about employment policies that allow women to stay at home longer, avoid contact with others, work in safe places,” she said.
The news comes amid the release of new CDC data on the safety of mRNA COVID-19 vaccines in pregnant people, with the federal agency saying that the vaccines are safe for those who are expecting or planning on becoming pregnant.
More specifically, the new CDC analysis found that receiving an mRNA COVID-19 vaccine early in pregnancy did not increase the risk of miscarriage. The analysis was based on data from nearly 2,500 pregnant women who got the shot before 20 weeks of pregnancy.
“CDC encourages all pregnant people or people who are thinking about becoming pregnant and those breastfeeding to get vaccinated to protect themselves from COVID-19,” said CDC Director Rochelle Walensky, MD, in a statement. “The vaccines are safe and effective, and it has never been more urgent to increase vaccinations as we face the highly transmissible Delta variant and see severe outcomes from COVID-19 among unvaccinated pregnant people.”