Immunogenicity of COVID-19 mRNA Vaccines in Pregnant and Lactating Women

Abstract

Pregnant women with symptomatic COVID-19 have a higher risk of intensive care unit admission, mechanical ventilation, and death compared with other women in their reproductive years.¹ Increases in preterm birth and stillbirth also have been observed in pregnancies complicated by COVID-19.² Maternal-fetal virus transmission in utero is rare,² and it appears that newborns receive passive immunity through antibody transfer via the placenta and from breast milk following natural infection.^3,4 Vaccination during pregnancy has reduced maternal morbidity and mortality from influenza and neonatal morbidity from pertussis through passive immunity.^5,6