Histopathological Changes in Placenta of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-Cov-2) Infection and Maternal and Perinatal Outcome in COVID-19

Background Whether vertical transmission or placental pathology occurs after maternal infection during pregnancy remains unknown. There is a clear need for studies on the impact of COVID-19 on pregnancy outcome. A systemic inflammatory or hypercoagulable state may be the contributing factor for placental pathology. Methods The pregnant women with COVID-19 who delivered between May 2020 and May 2021 were followed and data were collected about pregnancy course and placentas were examined for macro- and microscopical changes and were compared to controls with non-infected women. Results Placenta of COVID-19-infected females had increased prevalence of decidual arteriopathy and placental injury reflecting hypoxia and uteroplacental insufficiency within the intervillous space. Features of maternal vascular malperfusion such as increased syncytial knots were present in 100% cases. Fibrinoid necrosis was seen in 100% cases and increased focal perivillous fibrin depositions were presented in 37.7% cases. About one fourth infected placentas had evidence of villitis. Even after matching for comorbidities like preeclampsia, these changes were present. Conclusion The most common pathological findings of the placenta of COVID-19 infections are signs of maternal and fetal malperfusion. Future studies should target infections in different stage of gestation, including first and second trimesters.