Placental Pathology in COVID-19: Case Series in a Community Hospital Setting

Objective To report the histopathologic findings in the placentas of pregnant women with coronavirus disease-19 (COVID-19). Methods Pregnant women with COVID-19 delivering between April 2020 to June 2020 were identified. A retrospective study of placentas from COVID positive women received in the Department of Pathology, Monmouth Medical Center affiliate of Robert Wood Johnson Barnabas Health were examined and compared to control cohort of placentas from COVID negative women. The mothers were tested for coronavirus through nasopharyngeal swab upon admission to labor and delivery. The placentas from mothers who tested negative for the virus were sent to Pathology for examination based on the obstetrician's clinical judgment. Results Fifty surgical specimens (49 placentas and one product of conception) from patients positive for COVID-19 were examined and compared with fifty placentas from women with negative COVID-19 test results, who delivered during the same period. Most of the neonates had Appearance, Pulse, Grimace, Activity and Respiration (APGAR) scores of 9 and 9 at 1 and 5 minutes, respectively. Increased incidence of the COVID-19 positivity was noted in individuals with Rh-positive blood group A and Jewish heritage. Compared to the control group, the COVID-19 positive placentas showed increased features of malperfusion (microcalcifications, fibrin thrombi, syncytial knotting, and villous agglutination). However, there was no significant dysregulation in other variables, such as inflammation or coagulation. There was no case of maternal or fetal death (greater than eight weeks) or evidence of worse fetal outcomes noted due to a mother's positive COVID-19 status.  Conclusions The COVID-19 positive placentas showed an increased prevalence of microcalcifications and fibrin thrombi, which may reflect an underlying hypercoagulable state induced by COVID-19 infection or could be due to excessive syncytiotrophoblast injury.