Fetal Immune Response from Maternal Infection.

• Position: SARS-CoV-2

SARS-CoV-2 infection during pregnancy may cause inflammatory immune responses in the fetus, even if the virus does not infect the placenta. Researchers describe unique maternal, fetal, and placental immune responses among pregnant women with COVID-19 in a study led by the National Institute of Child Health and Human Development. The findings detail changes in antibodies, immune cell types, and inflammatory markers in maternal blood, umbilical cord blood, and placental tissues.

Pregnant women are at a higher risk for severe illness from COVID-19 compared to those who are not pregnant. COVID-19 during pregnancy also increases the risk for preterm birth, stillbirth, and preeclampsia.

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 sampling 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.

The study team described the following observations:

* Pregnant women with SARS-CoV-2 had a reduction in an...