SARS-CoV-2 may cause fetal inflammation even in the absence of placental infection

Tuesday, January 18, 2022

Small NIH study contributes to understanding of COVID-19 during pregnancy

SARS-CoV-2 infection during pregnancy may cause inflammatory immune responses in the fetus, even if the virus does not infect the placenta, according to a small National Institutes of Health study. Researchers describe unique maternal, fetal, and placental immune responses among pregnant women with COVID-19 in a study led by NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). The findings detail changes in antibodies, immune cell types and inflammatory markers in maternal blood, umbilical cord blood and placental tissues. The study is published in the journal Nature Communications.

People who are pregnant are at a higher risk for severe illness from COVID-19, compared to people who are not pregnant. COVID-19 during pregnancy also increases the risk for preterm birth, stillbirth and preeclampsia. Therefore, understanding COVID-19 infection during pregnancy is important to help healthcare providers optimize the health and safety of their patients during the pandemic.

The study evaluated 23 pregnant women. Twelve were positive for SARS-CoV-2, and of these, eight were asymptomatic, one had mild symptoms and three had severe COVID-19. After delivery, the researchers compared immune responses between mothers and their newborns by comparing maternal blood and umbilical cord blood. Inflammatory immune responses triggered by the virus were observed in women, their neonates and placental tissues regardless of whether the mothers had symptoms.