Intrauterine Fetal Demise in the Third Trimester of Pregnancy Associated With Mild Infection With the SARS-CoV-2 Delta Variant Without Protection From Vaccination

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a higher infection rate in pregnant women than age-matched adults. With increased infectivity and transmissibility, the Delta variant is predominant worldwide. Methods In this study, we describe intrauterine fetal demise in unvaccinated women with mild symptoms of SARS-CoV-2 Delta variant infection. Results Histology and elevated proinflammatory responses of the placenta suggest that fetal demise was associated with placental malperfusion due to Delta variant infection. Conclusions This study suggests that the Delta variant can cause severe morbidity and mortality to fetuses. Vaccination should continue to be advocated and will likely continue to reduce SARS-CoV-2 infection risks for pregnant women and their fetuses.