Clinical Characteristics of Mother-Infant Dyad and Placental Pathology in COVID-19 Cases in Predominantly African American Population

An Update on COVID-19-Associated Placental Pathologies

COVID-19 pregnancies are associated with increased rates of premature delivery and stillbirths. It is still a matter of debate whether there is a COVID-19-associated pattern of placenta pathology. We updated our previously published results on a systematic literature review and meta-analysis of COVID-19 pregnancies. In total, 38 reports on 3677 placentas were evaluated regarding histopathological changes. Maternal vascular malperfusion (32%), fetal vascular malperfusion (19%), acute and chronic inflammation (20% and 22%) were frequent pathologies. In non-COVID-19 pregnancies, placentas show similar histologic patterns and mainly similar frequencies of manifestation. It has to be taken into account that there might be an observation bias, because some findings are diagnosed as a "pathology" that might have been classified as minor or unspecific findings in non-COVID-19 placentas. COVID-19 placentitis occurs in 1-2% of cases at the most. In conclusion, this updated meta-analysis indicates that COVID-19 infection during pregnancy does not result in an increased rate of a specific placenta pathology and COVID-19 placentitis is rare.

Clinical Features of SARS-CoV-2 Infection During Pregnancy and Associated Placental Pathologies

SUMMARY

We reviewed the clinicopathologic findings of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-exposed placentas at our institution. We identified patients diagnosed with SARS-CoV-2 during pregnancy (March-October 2020). Clinical data included gestational age at diagnosis and delivery and maternal symptoms. Hematoxylin and eosin slides were reviewed for maternal vascular malperfusion, fetal vascular malperfusion, chronic villitis, amniotic fluid infection, intervillous thrombi, fibrin deposition, and infarction. Immunohistochemistry (IHC) for coronavirus spike protein and RNA in situ hybridization (ISH) for SARS-CoV-2 was performed on a subset of blocks. A review of placentas from age-matched patients received March-October 2019 was conducted as a comparison cohort. A total of 151 patients were identified. Placentas in the 2 groups were similar in weight for gestational age and had similar rates of maternal vascular malperfusion, fetal vascular malperfusion, amniotic fluid infection, intervillous thrombi, fibrin deposition, and infarction. Chronic villitis was the only significantly different pathologic finding between cases and controls (29% of cases showed chronic villitis vs. 8% of controls, P <0.001). Overall, 146/151 (96.7%) cases were negative for IHC and 129/133 (97%) cases were negative for RNA ISH. There were 4 cases that stained positively for IHC/ISH, 2 of which showed massive perivillous fibrin deposition, inflammation, and decidual arteriopathy. Coronavirus disease 2019 (COVID-19)-positive patients were more likely to self-identify as Hispanic and more likely to have public health insurance. Our data suggests SARS-CoV-2 exposed placentas that stain positively for SARS-CoV-2 show abnormal fibrin deposition, inflammatory changes, and decidual arteriopathy. The group of patients with clinical COVID-19 are more likely to show chronic villitis. IHC and ISH evidence of viral infection is rare.

A Review of the Prevalence of Thromboembolic Complications among Pregnant Women Infected with COVID-19

Background: Thrombotic conditions triggered by SARS-CoV-2 virus can result in high mortality, especially in pregnant women as they are already in a hypercoagulability state. This thereby leads to excessive inflammation that will increase the risk of thromboembolic (TE) complications. Objective: The aim of this study is to review the prevalence of thromboembolic complications such as deep venous thrombosis, pulmonary embolism, and intervillous thrombosis, and their preventive strategies among pregnant women infected with COVID-19. Method: The articles were retrieved from online databases PubMed and ScienceDirect published from February 2020 to April 2022. Findings: A total of 5249 participants including 5128 pregnant women and 121 placentas from 19 studies were identified for having TE complications after being infected with COVID-19. The types of TE complications that developed within pregnant women were disseminated intravascular coagulation (DIC) (n = 44, 0.86%), unmentioned thromboembolic complications (TE) (n = 14, 0.27%), intervillous thrombosis (IVT) (n = 9, 0.18%), pulmonary embolism (PE) (n = 6, 0.12%), COVID-19 associated coagulopathy (CAC) (n = 5, 0.10%), and deep venous thrombosis (DVT) (n = 2, 0.04%). Whereas the prevalence of TE complications reported from studies focusing on placenta were IVT (n = 27, 22.3%), subchorionic thrombus (SCT) (n = 9, 7.44%), and placental thrombosis (n = 5, 4.13%). Thromboprophylaxis agent used among pregnant women include low molecular weight heparin (LMWH) at prophylactic dose (n = 9). Conclusions: The prevalence of thromboembolic complications among pregnant women infected by COVID-19 is low with DIC being the most common form and placental thrombosis being the least common form of TE complications that occurred within pregnant women infected with COVID-19. Anticoagulation, in particular LMWH (variable dose), is frequently used to prevent TE complications.

The COVID-19 Pandemic and Pregnancy: Impact on Mothers and Newborns

The severe acute respiratory syndrome coronavirus 2 pandemic has markedly, and likely permanently, changed health care. This includes changing the obstetric and perinatal care of mothers and infants, and by extension, the care of their families. Infection during pregnancy is associated with an increased risk for severe coronavirus disease 2019 illness and related complications that can significantly impact maternal health and the health of the neonate. Viral transmission from mother to fetus is possible, but rare during pregnancy, and current health care policies focusing on maternal masking, and hand washing allows infected mothers to safely care for neonates (including nursing or feeding with expressed breast milk). The newly developed vaccines have been shown to be safe and effective for pregnant and breast-feeding mothers, with measurable antibody levels in cord blood and breast milk potentially providing a level of passive immunity to neonates. While studies looking at short-term outcomes for neonates have been reassuring, it is critical that we continue to work to understand and improve the care of pregnant woman and newborns with coronavirus disease 2019 to optimize long term outcomes. Although the knowledge base continues to evolve, the available evidence influencing the care of pregnant women and their infants is summarized in this focused review.

Pathological involvement of placenta in COVID-19: a systematic review

The mammalian placenta, which is responsible for bonding between the mother and the fetus, is one of the first organs to develop. Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection has caused a great threat to public health and affected almost all the organs including the placenta. Owing to limited available data on vertical transmission and pathological changes in the placenta of SARS-CoV-2 positive patients, we aim to review and summarize histopathological and ultrastructural changes in the placental tissue following SARS-CoV-2 infection. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 guidelines were used for review writing. Multiple studies have reported significant pathological changes in the placental tissue of SARS-CoV-2 positive mothers. On the other hand, some studies have demonstrated either no or very little involvement of the placental tissue. The most common pathological changes reported are fetal and maternal vascular malformation, villitis of unknown etiology, thrombus formation in the intervillous space and sub-chorionic space, and chorangiosis. Reports on vertical transmission are less in number. The observations of this review present a strong base for the pathological involvement of the placenta in SARS-CoV-2 infected mothers. However, a smaller number of original studies have been done until now, and most of them have small sample sizes and lack matched control groups, which are the big limitations for drawing an effective conclusion at this stage. Antenatal care can be improved by a better understanding of the correlation between maternal SARS-CoV-2 infection and placental pathology in COVID-19.

Anesthesia Considerations for Pregnant People With COVID-19 Infection

The purpose of this review is to describe updates following initial recommendations on best anesthesia practices for obstetric patients with coronavirus disease 2019. The first surge in the United States prompted anesthesiologists to adapt workflows and reconsider obstetric anesthesia care, with emphasis on avoidance of general anesthesia, the benefit of early neuraxial labor analgesia, and prevention of emergent cesarean delivery whenever possible. While workflows have changed to allow sustained safety for obstetric patients and health care workers, it is notable that obstetric anesthesia protocols for labor and delivery have not significantly evolved since the first coronavirus disease 2019 wave.

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

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.

Placental histopathology after SARS-CoV-2 infection in pregnancy: a systematic review and meta-analysis

OBJECTIVE

This study aimed to report the spectrum of placental pathology findings in pregnancies complicated by SARS-CoV-2 infection.

DATA SOURCES

MEDLINE, Embase, Google Scholar, and the Web of Science databases were searched up to August 11, 2021.

STUDY ELIGIBILITY CRITERIA

Histopathologic anomalies included maternal vascular malperfusion, fetal vascular malperfusion, acute inflammatory pathology, chronic inflammatory pathology, increased perivillous fibrin, and intervillous thrombosis. Moreover, subanalyses of symptomatic women only and high-risk pregnancies were performed.

METHODS

Histopathologic analysis of the placenta included gross examination, histopathology on hematoxylin and eosin, immunohistochemistry, fluorescence in situ hybridization, quantitative reverse transcription-polymerase chain reaction on placental tissue, and transmission electron microscope. Random-effect meta-analyses were used to analyze the data.

RESULTS

A total of 56 studies (1008 pregnancies) were included. Maternal vascular malperfusion was reported in 30.7% of placentas (95% confidence interval, 20.3-42.1), whereas fetal vascular malperfusion was observed in 27.08 % of cases (95% confidence interval, 19.2-35.6). Acute and chronic inflammatory pathologies were reported in 22.68% (95% confidence interval, 16.9-29.0) and 25.65% (95% confidence interval, 18.4-33.6) of cases, respectively. Increased perivillous fibrin was observed in 32.7% (95% confidence interval, 24.1-42.0) of placentas undergoing histopathologic analysis, whereas intervillous thrombosis was observed in 14.6% of cases (95% confidence interval, 9.7-20.2). Other placental findings, including a basal plate with attached myometrial fibers, microscopic accretism, villous edema, increased circulating nucleated red blood cells, or membranes with hemorrhage, were reported in 37.5% of cases (95% confidence interval, 28.0-47.5), whereas only 17.5% of cases (95% confidence interval, 10.9-25.2) did not present any abnormal histologic findings. The subanalyses according to maternal symptoms owing to SARS-CoV-2 infection or the presence of a high-risk pregnancy showed a similar distribution of the different histopathologic anomalies to that reported in the main analysis. Moreover, the risk of placental histopathologic anomalies was higher when considering only case-control studies comparing women with SARS-CoV-2 infection with healthy controls.

CONCLUSION

In pregnant women with SARS-CoV-2 infection, a significant proportion of placentas showed histopathologic findings, suggesting placental hypoperfusion and inflammation. Future multicenter prospective blinded studies are needed to correlate these placental lesions with pregnancy outcomes.

Asymptomatic SARS-CoV-2 infection: A systematic review and meta-analysis

Quantification of asymptomatic infections is fundamental for effective public health responses to the COVID-19 pandemic. Discrepancies regarding the extent of asymptomaticity have arisen from inconsistent terminology as well as conflation of index and secondary cases which biases toward lower asymptomaticity. We searched PubMed, Embase, Web of Science, and World Health Organization Global Research Database on COVID-19 between January 1, 2020 and April 2, 2021 to identify studies that reported silent infections at the time of testing, whether presymptomatic or asymptomatic. Index cases were removed to minimize representational bias that would result in overestimation of symptomaticity. By analyzing over 350 studies, we estimate that the percentage of infections that never developed clinical symptoms, and thus were truly asymptomatic, was 35.1% (95% CI: 30.7 to 39.9%). At the time of testing, 42.8% (95% prediction interval: 5.2 to 91.1%) of cases exhibited no symptoms, a group comprising both asymptomatic and presymptomatic infections. Asymptomaticity was significantly lower among the elderly, at 19.7% (95% CI: 12.7 to 29.4%) compared with children at 46.7% (95% CI: 32.0 to 62.0%). We also found that cases with comorbidities had significantly lower asymptomaticity compared to cases with no underlying medical conditions. Without proactive policies to detect asymptomatic infections, such as rapid contact tracing, prolonged efforts for pandemic control may be needed even in the presence of vaccination.

Placental histopathology after SARS-CoV-2 infection in pregnancy: a systematic review and meta-analysis

OBJECTIVE

This study aimed to report the spectrum of placental pathology findings in pregnancies complicated by SARS-CoV-2 infection.

DATA SOURCES

MEDLINE, Embase, Google Scholar, and the Web of Science databases were searched up to August 11, 2021.

STUDY ELIGIBILITY CRITERIA

Histopathologic anomalies included maternal vascular malperfusion, fetal vascular malperfusion, acute inflammatory pathology, chronic inflammatory pathology, increased perivillous fibrin, and intervillous thrombosis. Moreover, subanalyses of symptomatic women only and high-risk pregnancies were performed.

METHODS

Histopathologic analysis of the placenta included gross examination, histopathology on hematoxylin and eosin, immunohistochemistry, fluorescence in situ hybridization, quantitative reverse transcription-polymerase chain reaction on placental tissue, and transmission electron microscope. Random-effect meta-analyses were used to analyze the data.

RESULTS

A total of 56 studies (1008 pregnancies) were included. Maternal vascular malperfusion was reported in 30.7% of placentas (95% confidence interval, 20.3-42.1), whereas fetal vascular malperfusion was observed in 27.08 % of cases (95% confidence interval, 19.2-35.6). Acute and chronic inflammatory pathologies were reported in 22.68% (95% confidence interval, 16.9-29.0) and 25.65% (95% confidence interval, 18.4-33.6) of cases, respectively. Increased perivillous fibrin was observed in 32.7% (95% confidence interval, 24.1-42.0) of placentas undergoing histopathologic analysis, whereas intervillous thrombosis was observed in 14.6% of cases (95% confidence interval, 9.7-20.2). Other placental findings, including a basal plate with attached myometrial fibers, microscopic accretism, villous edema, increased circulating nucleated red blood cells, or membranes with hemorrhage, were reported in 37.5% of cases (95% confidence interval, 28.0-47.5), whereas only 17.5% of cases (95% confidence interval, 10.9-25.2) did not present any abnormal histologic findings. The subanalyses according to maternal symptoms owing to SARS-CoV-2 infection or the presence of a high-risk pregnancy showed a similar distribution of the different histopathologic anomalies to that reported in the main analysis. Moreover, the risk of placental histopathologic anomalies was higher when considering only case-control studies comparing women with SARS-CoV-2 infection with healthy controls.

CONCLUSION

In pregnant women with SARS-CoV-2 infection, a significant proportion of placentas showed histopathologic findings, suggesting placental hypoperfusion and inflammation. Future multicenter prospective blinded studies are needed to correlate these placental lesions with pregnancy outcomes.

Management of maternal COVID-19: considerations for anesthesiologists

PURPOSE OF REVIEW

To describe updates to pragmatic recommendations that were published during the first coronavirus disease 2019 (COVID-19) surge, including the current thinking about whether pregnancy worsens the severity of COVID-19.

RECENT FINDINGS

Although a majority of pregnant women infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain asymptomatic or paucisymptomatic, pregnancy puts women at higher risk of severe COVID-19 and adverse birth outcomes. Pregnant and recently pregnant women are more likely to be admitted to intensive care units and receive mechanical ventilation than nonpregnant patients with COVID-19, although preexisting maternal comorbidities are significant risk factors.Early provision of neuraxial labor analgesia with a functional indwelling epidural catheter has been universally promoted, with the goal to reduce avoidable general anesthesia for cesarean delivery and mitigate risks for healthcare workers during airway manipulation. This recommendation, along with updated workflow models of anesthesia coverage, may contribute to a reduction in general anesthesia rates.

SUMMARY

Initial recommendations to provide early neuraxial labor analgesia and avoid general anesthesia for cesarean delivery have not changed over time. Although workflows have significantly changed to allow continued patient and healthcare workers' safety, clinical anesthesia protocols for labor and delivery are essentially the same.