<p>Background: Although the risk for transplacental transmission of SARS-CoV-2 is rare, placental infections with adverse functional consequences have been reported. This study aims to analyse histological placental findings in pregnancies complicated by SARS-CoV-2 infection and investigate its correlation with clinical symptoms and perinatal outcomes. We want to determine which pregnancies are at-risk to prevent adverse pregnancy outcomes related to COVID-19 in the future. Methods: A prospective, longitudinal, multicentre, cohort study. All pregnant women presenting between April 2020 and March 2021 with a nasopharyngeal RT-PCR-confirmed SARS-CoV-2 infection were included. Around delivery, maternal, foetal and placental PCR samples were collected. Placental pathology was correlated with clinical maternal characteristics of COVID-19. Results: Thirty-six patients were included, 33 singleton pregnancies (n = 33, 92%) and three twin pregnancies (n = 3, 8%). Twenty-four (62%) placentas showed at least one abnormality. Four placentas (4/39, 10%) showed placental staining positive for the presence of SARS-CoV-2 accompanied by a unique combination of diffuse, severe inflammatory placental changes with massive perivillous fibrin depositions, necrosis of syncytiotrophoblast, diffuse chronic intervillositis, and a specific, unprecedented CD20+ B-cell infiltration. This SARS-CoV-2 placental signature seems to correlate with foetal distress (75% vs. 15.6%, p = 0.007) but not with the severity of maternal COVID-19 disease. Conclusion: We describe a unique placental signature in pregnant patients with COVID-19, which has not been reported in a historical cohort. We show that the foetal environment can be seriously compromised by disruption of placental function due to local, devastating SARS-CoV-2 infection. Maternal clinical symptoms did not predict the severity of the SARS-CoV-2-related placental signature, resulting in a lack of adequate identification of maternal criteria for pregnancies at risk. Close foetal monitoring and pregnancy termination in case of foetal distress can prevent adverse pregnancy outcomes due to COVID-19 related placental disease.</p>

doi.org/10.3390/v13081670, hdl.handle.net/1765/136616
Erasmus MC: University Medical Center Rotterdam

M.F. (Marjolein) Husen, Lotte E. van der Meeren, R.M. (Rob) Verdijk, P.L.A. (Pieter) Fraaij, A.A. (Annemiek) Baltissen - van der Eijk, M.P.G. (Marion) Koopmans, … S. (Sam) Schoenmakers. (2021). Unique severe covid-19 placental signature independent of severity of clinical maternal symptoms. Viruses, 13(8). doi:10.3390/v13081670