Placental Pathology in COVID-19

  1. Elisheva D Shanes
  2. Leena B Mithal
  3. Sebastian Otero
  4. Hooman A Azad
  5. Emily S Miller
  6. Jeffery A Goldstein

Reviewed by

Read the full article

Listed in

Log in to save this article

Abstract

Objectives

To describe histopathologic findings in the placentas of women with coronavirus disease 2019 (COVID-19) during pregnancy.

Methods

Pregnant women with COVID-19 delivering between March 18, 2020, and May 5, 2020, were identified. Placentas were examined and compared to historical controls and women with placental evaluation for a history of melanoma.

Results

Sixteen placentas from patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were examined (15 with live birth in the third trimester, 1 delivered in the second trimester after intrauterine fetal demise). Compared to controls, third trimester placentas were significantly more likely to show at least one feature of maternal vascular malperfusion (MVM), particularly abnormal or injured maternal vessels, and intervillous thrombi. Rates of acute and chronic inflammation were not increased.

The placenta from the patient with intrauterine fetal demise showed villous edema and a retroplacental hematoma.

Conclusions

Relative to controls, COVID-19 placentas show increased prevalence of decidual arteriopathy and other features of MVM, a pattern of placental injury reflecting abnormalities in oxygenation within the intervillous space associated with adverse perinatal outcomes. Only 1 COVID-19 patient was hypertensive despite the association of MVM with hypertensive disorders and preeclampsia. These changes may reflect a systemic inflammatory or hypercoagulable state influencing placental physiology.

Article activity feed

  1. ScreenIT

    SciScore for 10.1101/2020.05.08.20093229: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board StatementIRB: This study was approved by our Institutional Review Board, STU00207907 (historical and melanoma controls), STU00212232 (COVID-19 cases).
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.
    Sex as a biological variablePatients: Pregnant women with COVID-19 delivering between March 18, 2020 and May 5, 2020 were identified via the electronic health record and tracked using REDCap.18 From March 18, 2020 until April 7, 2020, only women with moderate to severe symptoms of COVID-19 underwent testing.

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    To do this, individual bullet points were tokenized and stemmed using the Porter stemmer function of the Natural Language Toolkit (nltk) package (version 3.3) on Python (version 3.6.5).
    Python
    suggested: (IPython, RRID:SCR_001658)

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    This study is subject to some limitations. The relatively low number of patients limits our assessment of low frequency or variable outcomes. We have grouped symptomatic, asymptomatic, and recovered patients - a larger study could treat these groups separately. One strength of our study is the use of 2 distinct control groups. Placentas are only submitted for clinical examination when there is an indication - usually diseases in pregnancy or complications of labor and delivery. Melanoma history is an indication for placental examination but is considered independent of pregnancy outcome, and therefore some have advocated using these patients as a control. Nonetheless, more appropriate control populations could include patients with influenza-like illness with negative SARS-CoV-2 testing and asymptomatic, COVID-19 negative patients delivering at a similar time. Finally, our study does not formally test causality or the direct relationship between SARS-CoV-2 infection and development of placental pathology. It is possible that viral infection directly leads to placental pathology or that there is a common underlying cause for both placental lesions and susceptibility to SARS-CoV-2.

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  2. Version published to 10.1093/ajcp/aqaa089
  3. Version published to 10.1101/2020.05.08.20093229v1 on medRxiv