According to a study published in JAMA, pregnant women infected with COVID-19 who were either asymptomatic or symptomatic passed SARS-CoV-2 antibodies to their newborns during pregnancy via the placenta.
Researchers say their findings show the potential of maternal antibodies to provide neonatal protection against COVID-19.
Among 1471 mother/newborn dyads for which matched sera were available, SARS-CoV-2 IgG and/or IgM antibodies were detected in 83 of 1471 women (6%) at the time of delivery, and IgG was detected in cord blood from 72 of 83 newborns (87%).
Women with moderate or critical illness had higher IgG and IgM concentrations, and infants born to these women had higher IgG concentrations, but these differences were not statistically significant. Transfer ratios were not different among infants born to mothers with asymptomatic or symptomatic illness.