Placental Pathology in COVID-19

Area of Science:

• Obstetrics and Gynecology
• Pathology
• Infectious Diseases

Background:

• Pregnancy involves significant physiological changes that can alter susceptibility to infections.
• Coronavirus disease 2019 (COVID-19) in pregnant individuals can lead to various maternal and fetal complications.
• Placental pathology plays a crucial role in understanding pregnancy outcomes.

Purpose of the Study:

• To characterize the histopathologic features of placentas from pregnancies complicated by COVID-19.
• To identify specific placental changes associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

Main Methods:

• Retrospective analysis of placentas from 16 pregnant women with COVID-19.
• Histopathologic examination of placental tissues.
• Comparison with historical control placentas and those from women with a history of melanoma.

Main Results:

• Third-trimester placentas from COVID-19 patients showed a higher incidence of maternal vascular malperfusion (MVM) features, including abnormal maternal vessels and intervillous thrombi, compared to controls.
• No significant increase in acute or chronic placental inflammation was observed.
• The placenta from a second-trimester intrauterine fetal demise case exhibited villous edema and retroplacental hematoma.

Conclusions:

• COVID-19 placentas demonstrate an increased prevalence of decidual arteriopathy and other MVM features, indicating impaired intervillous space oxygenation.
• These placental findings may be linked to adverse perinatal outcomes and suggest a potential systemic inflammatory or hypercoagulable state.
• The association of MVM with hypertensive disorders was noted, although only one COVID-19 patient was hypertensive.