Ultrasound Obstet Gynecol. 2022 Mar 30. doi: 10.1002/uog.24906. Online ahead of print.
ABSTRACT
OBJECTIVES: To report the causative relationship of maternal COVID-19 with intrauterine fetal death, describe the specific placental pathology, findings of fetal autopsy and clinical characteristics, and identify potential risk factors.
METHODS: This is a prospective case series. A cohort of 165 placentas of non-vaccinated pregnant women affected by COVID-19 in Greece were histologically examined and six cases of intrauterine fetal death associated with SARS-COV-2 placentitis were retrieved. Complete fetal autopsy was performed in three cases. Gross, histopathological, immunohistochemical, molecular, and electron microscopy examinations were carried out in the stillbirth placentas and fetal organs. The histological findings of SARS-COV-2 placentitis were compared with the 159 cases, in which maternal COVID-19 resulted in livebirth. Regression analysis was used to identify predisposing factors for SARS-COV-2 placentitis.
RESULTS: All six stillbirth placentas showed severe and extensive histological changes of SARS-COV-2 placentitis, i.e. a combination of marked intervillositis with a mixed inflammatory infiltrate and massive perivillous fibrinoid deposition with trophoblast damage, associated with intensely positive immunostaining for SARS-COV-2 spike protein, the presence of virions on electron microscopy and a positive RT-PCR test in placental tissues. The histological lesions obliterated over 75% of the maternal intervillous space, accounting for intrauterine fetal death. Similar histological lesions affecting less than 25% of the placenta were recorded in 7 liveborn neonates, while the remaining 152 placentas of COVID-19-affected pregnancies with livebirths did not show similar findings. Complete fetal autopsy showed evidence of an asphyctic mode of death without evidence of viral transmission to the fetus. The mothers had mild clinical symptoms or were asymptomatic and the interval between maternal COVID-19 diagnosis and fetal death ranged from 3 to 15 days. Statistically significant predisposing factors for SARS-COV-2-placentitis included thrombophilia and IUGR. Multiple sclerosis was seen in one case.
CONCLUSIONS: SARS-COV-2 placentits occurred uncommonly in COVID-19-affected pregnancies of non-vaccinated mothers and, when extensive, caused fetal demise, with no evidence of transplacental fetal infection. Thrombophilia and prenatally detected IUGR emerged as independent predisposing factors for the potentially lethal SARS-COV-2 placentitis. This article is protected by copyright. All rights reserved.
PMID:35353936 | DOI:10.1002/uog.24906
