SARS-CoV2 vaccination during pregnancy – Vetting the impact on maternal health and long-term consequences for offspring brain function

The COVID-19 pandemic has shown the critical importance of vaccination strategies to protect vulnerable populations, including pregnant women, from severe disease and its lingering consequences. Although growing evidence demonstrates that COVID-19 vaccines are both safe and highly beneficial during pregnancy, vaccine hesitancy among pregnant women persists, partly fueled by the persistent, decade-old "urban myth" linking vaccination during pregnancy to neuropsychiatric disorders in children. Here we used a mouse model of passive immunization with severe acute respiratory syndrome coronavirus 2 spike neutralizing monoclonal antibodies (SaCoV-AB) to determine the effects of gestational COVID-19 vaccination on key pregnancy outcomes, maternal and offspring health, and behavior. We show that at a higher SaCoV-AB dosage, maternal immune response is reflected in elevated TNF-α levels in maternal serum, but not in the placenta or the fetal brain, with no effect on pregnancy outcomes. We report no consequences for postpartum maternal care behavior and neonatal communication signatures. Behavioral assessment of adult female and male offspring after maternal SaCoV-AB treatment revealed no differences in phenotypes relevant to neurodevelopmental disorders. Our findings indicate that in a preclinical model, passive immunization with SaCoV-AB during pregnancy is well-tolerated, with no discernable impact on maternal or offspring health and behavior.