Histomorphological evaluation of placenta in SARS-CoV-2 patients: A cross-sectional study

SARS-CoV-2 has emerged as a major pandemic of the century and little is known about the impact of maternal infection on placental histopathology. Histopathologic examination of placental tissue can contribute to significant information regarding the pathophysiology of the disease and how it affects the fetal outcome.

This was a cross-sectional study conducted at the Department of Pathology, Government Doon Medical College and Hospital, Dehradun, on the placenta of 50 coronavirus disease 2019 (COVID-19)-positive pregnant females confirmed by reverse transcriptase-polymerase chain reaction (RT-PCR) from August 2020 to October 2020. Fifty term historical placentas were taken as control. Placenta sections were fixed in formalin, processed into paraffin blocks, stained with hematoxylin and eosin (H and E) stain, and visualized for any abnormality.

The most prominent histological finding in the placenta of pregnant women affected by COVID-19 was chorangiosis, which is a feature of fetal vascular malperfusion seen in 28 (56%) cases. Other features included maternal vascular malperfusions (MVM) such as villous crowding and agglutination in 12 (24%) cases. Tenney-Parker change was seen in 13 (26%) patients. Intervillous fibrinoid deposition and intervillous hemorrhage were seen in 37 (74%) patients and 7 (14%) patients showed significant calcification. Other findings observed were less common.

Infection with SARS-CoV-2 may be associated with a significant impact on fetal and maternal circulation causing features of fetal and maternal malperfusion such as chorangiosis, villous crowding, and agglutination. Indicating that the infection could cause a potential rise in the risk of adverse perinatal outcomes such as intrauterine fetal growth retardation, preterm birth, or stillbirth.