Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Vaccination in Pregnancy

Vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been approved for emergency use, but, despite elevated risk of severe disease, pregnant women were excluded from the clinical trials that led to their authorization.1 Placental findings can indicate potential clinical risk and could be an early signal for rare injury seen only after widespread use in the pregnant population.2–6 Maternal SARS-CoV-2 infection has been associated with decidual arteriopathy, fetal vascular malperfusion, and chronic histiocytic intervillositis.7–9 mRNA vaccines induce an immune response through activation of TLR3, which has been linked to decidual arteriopathy, growth restriction, preterm delivery, and fetal loss in mouse models.10–14 Our objective was to evaluate the frequency of these key placental lesions in patients who received SARS-CoV-2 vaccination in pregnancy.