Antibodies in neonatal cord blood

In Obstetrics and Gynecology, researchers report on a case of transplacental transfer of neutralizing SARS-CoV-2 antibodies after vaccination during pregnancy. A woman received both doses of the Pfizer-BioNTech vaccine during her third trimester. She delivered vaginally at roughly 39 weeks’ gestation, without maternal or neonatal complications. Maternal and cord blood samples both tested positive for immunoglobulin G (titer, 1:25,600). Maternal SARS-CoV-2 PCR tests during pregnancy and a prior antibody test all had yielded negative results, indicating that the antibodies were from the vaccine and not natural infection. The authors note that other vaccines, such as those for pertussis and flu, offer neonatal protection when they are administered during pregnancy. They conclude, “Our case supports that this may also be true for the SARS-CoV-2 vaccine.”

Obstetrics & Gynecology case report on antibodies in cord blood