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

Placenta. 2022 Jan:117:72-77. doi: 10.1016/j.placenta.2021.10.010. Epub 2021 Oct 19.

Abstract

Coronavirus disease 2019 (COVID-19) pneumonia rarely occurs in pregnant women. Case reports indicate that fibrin and lymphohistiocytic lesions in placentas may be typical. However, a meta-analysis to clarify whether there is a COVID-19-associated pattern of placental lesions has not yet been conducted. Systematic literature search with meta-analysis of publications on 10 or more cases of pregnancy with SARS-CoV-2 infection and placenta examination (30 publications from 2019 to 2021; 1452 placenta cases) was performed. The meta-analysis did not reveal any COVID-19-specific placenta changes. The incidence of both vascular and inflammatory lesions was mainly comparable to that of non-COVID-19 pregnancies. Transplacental viral transmission is very rare and there are no typical placental changes. The most important prognostic factor seems to be maternal-fetal hypoxia in the context of pneumonia.

Keywords: COVID-19; Histology; Pathology; Placenta; Pregnancy.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Adult
  • COVID-19 / complications*
  • COVID-19 / pathology
  • COVID-19 / transmission
  • Female
  • Fetal Hypoxia / virology
  • Humans
  • Hypoxia / virology
  • Infectious Disease Transmission, Vertical / statistics & numerical data
  • Placenta / pathology*
  • Pregnancy
  • Pregnancy Complications, Infectious / pathology
  • Pregnancy Complications, Infectious / virology*
  • SARS-CoV-2*