Histopathology of Third Trimester Placenta from SARS-CoV-2-Positive Women

Abstract

Background: This study aims to investigate whether maternal SARS-CoV-2 status affect placental pathology. Methods: A retrospective case-control study was conducted by reviewing charts and slides of placentas between April 1 to July 24, 2020. Clinical history of COVID-19 were searched in Pathology Database (CoPath). Controls were matched with SARS-CoV-2-negative women with singleton deliveries in the 3rd-trimester. Individual and group, pathological features were extracted from placental pathology reports. Results: Twenty-one 3rd-trimester, placentas from SARS-CoV-2-positive women were identified and compared to 20 placentas from SARS-CoV-2-negative women. There were no significant differences in individual or group gross or microscopic pathological features between the groups. Within the SARS-CoV-2+ group, there are no differences between symptomatic and asymptomatic women. Conclusion: Placentas from SARS-CoV-2-positive women do not demonstrate a specific pathological pattern. Pregnancy complicated with COVID-19 during the 3rd trimester does not have a demonstrable effect on placental structure and pathology.

Meta-analysis on COVID-19-pregnancy-related placental pathologies shows no specific pattern

“…We identified a total of 1452 cases from 30 publications [ [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] , [41] ] ( Table 1 ). It should be taken into consideration that histological changes were not graded in all publications and even minor changes could have been summarized as “pathology”.…”

Defining Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Placentitis

“…Results of early studies examining the effects of maternal SARS-CoV-2 infection on the placenta suggested an association between maternal SARS-CoV-2 infection and maternal or fetal vascular malperfusion [8][9][10][11][12][13][14][15] however later studies failed to support these conclusions [13][14][15][16][17] These early studies were largely retrospective reviews of placentas from all SARS-CoV-2 infected mothers, irrespective of active placental infection (i.e., no confirmation of SARS-CoV-2 infection in the placental parenchyma). More recently, case reports with confirmatory testing for active placental infection have highlighted recurring features of chronic histiocytic intervillositis, 4,[18][19][20][21][22][23][24][25] villous trophoblast necrosis, 4,18,[23][24][25][26] and, to varying extents, intervillous fibrin deposition.…”

SARS-CoV-2 can infect and propagate in human placenta explants

“…15 Furthermore, there are indications from several case reports that SARS-CoV-2 infection during pregnancy is associated with placental pathological changes, including placentitis, intervillositis, fibrin deposition, and decidual vascular injury. 14,[16][17][18][19] Moreover, placental infection was reported with the presence of the viral RNA in the umbilical cord, the placental villi, fetal membranes, and trophoblasts, raising concerns that SARS-CoV-2 could affect fetal development. 20,21 Severe neonatal COVID-19 is described and sporadic cases of vertical transmission were reported.…”