Transplacental transmission of SARS-CoV-2 infection

Multisystem inflammatory syndrome in neonates associated with pneumothorax: Case report

The coronavirus disease 2019 (COVID-19) pandemic that was spread worldwide since 2019 and showed a highly contagious character affecting the lifestyle of people worldwide causing symptoms that are not limited to the respiratory system only but had multi-systemic effects that may progress to severe complications that roughly affect people's health. A newly recognized SARS-CoV-2-associated syndrome called pediatric multisystem inflammatory syndrome has been described worldwide. Initially, it was reported as hyper-inflammatory shock and "Kawasaki-like" symptoms with fever and conjunctivitis, a similar syndrome is also reported in neonates and called Multisystem Inflammatory Syndrome of neonates (MIS-N). In this paper, we presented a case of a newborn baby girl born by caesarian section affected by multisystem inflammatory syndrome of neonates presenting with respiratory distress on her third day of life, then she developed bilateral pneumothorax and pneumomediastinum respectively that required intubation, which highlights that the recognition of pneumothorax and pneumomediastinum as potential presentations of immunoglobulin G (IgG) positive MIS-N in newborns remains crucial.

Transplacental Transmission of SARS-CoV-2: A Narrative Review

Background and Objectives: The study aims to explore the potential for transplacental transmission of SARS-CoV-2, focusing on its pathophysiology, placental defense mechanisms, and the clinical implications for maternal and neonatal health. Materials and Methods: A comprehensive review of the current literature was conducted, analyzing studies on SARS-CoV-2 infection in pregnancy, the expression of key viral receptors (ACE2 and TMPRSS2) in placental cells, and the immune responses involved in placental defense. The review also examined the clinical outcomes related to maternal and neonatal health, including adverse pregnancy outcomes and neonatal infection. Results: The expression of ACE2 and TMPRSS2 in the placenta supports the biological plausibility of SARS-CoV-2 transplacental transmission. Histopathological findings from the infected placentas reveal inflammation, vascular changes, and the evidence of viral particles in placental tissues. Clinical reports indicate an increased risk of preterm birth, intrauterine growth restriction, and neonatal infection in pregnancies affected by COVID-19. However, the frequency and mechanisms of vertical transmission remain variable across studies, highlighting the need for standardized research protocols. Conclusions: SARS-CoV-2 can potentially infect placental cells, leading to adverse pregnancy outcomes and neonatal infection. While evidence of transplacental transmission has been documented, the risk and mechanisms are not fully understood. Ongoing research is essential to clarify these aspects and inform obstetric care practices to improve maternal and neonatal outcomes during the COVID-19 pandemic.

SARS-CoV-2 replicates in the placenta after maternal infection during pregnancy

Objectives

Pregnant women are at increased risk for severe SARS-CoV-2 infection and adverse neonatal outcome, primarily preterm birth and stillbirth. Our study aimed to investigate to which extent SARS-CoV-2 affects placental tissue and if viral replication within the placenta is evident, thus if there is a correlation between placental damage and adverse pregnancy outcome such as stillbirth.

Methods

We prospectively collected placentas from 61 SARS-CoV-2 infected pregnant women and 10 controls. Histopathological, immunohistochemical, and in situ hybridization studies were performed on all placentas with antibodies for SARS-CoV-2 proteins, ACE2, various immune cells, and inflammatory markers or probes for SARS-CoV-2 genes and an antisense strand.

Results

The measured scores of SARS-CoV-2 glycoprotein, nucleocapsid, and antisense strand indicating replication correlated with both the severity of maternal symptoms and presence of stillbirth. Specifically, 15/61 placentas exhibited replication, while the three cases with stillbirth had high or maximal replication scores. ACE2-H-score was significantly higher in COVID-19 patients, while the expression of various immune cells did not differ statistically. In multivariate analysis, presence of maternal comorbidities correlated with presence of severe COVID-19 infection.

Conclusion

We report evidence of active in vivo SARS-CoV-2 replication in the placenta after maternal infection in pregnancy in a case-control setting in a large population. Intensity of placental viral replication as well as viral levels were higher in women with severe or critical COVID-19 disease, supporting the rationale that severity of maternal SARS-CoV-2 infection could correlate with the severity of placentitis. Replication was maximal in cases of stillbirth, which suggests direct placental involvement in the pathophysiology of this dramatic outcome. Continuing to advocate for preventive measures against COVID-19 during pregnancy, including (re)vaccination, as well as appropriately counseling women with diagnosed infection, are of utter importance.

SARS-CoV-2 infection during pregnancy: clinical characteristics and vertical transmission in a referral hospital in Peru

Motivation for the study. There is a gap in knowledge about vertical transmission of SARS- CoV-2 and its implications for maternal and neonatal health, despite evidence of multisystem involvement in pregnant women with COVID-19. Main findings. The study results suggest low incidence of vertical transmission during pregnancy, with only one PCR-positive case in the placenta and one asymptomatic neonate. Implications. Our results can inform strategies for prevention and management of COVID-19 in pregnant women, as well as guide the development of health policies aimed at protecting maternal and neonatal health during the pandemic. The aim of this study was to analyze the vertical transmission of SARS-CoV-2 in pregnant women with COVID-19 in the Gynecology and Obstetrics Department of the Edgardo Rebagliati Martins National Hospital (HNERM). Twelve pregnant women who met the inclusion criteria were included. Real-time PCR (RT-PCR) tests for SARS-CoV-2 were performed when each woman was admitted to the hospital, placenta samples were collected for pathological evaluation as well. The results showed that vertical transmission of the virus was rare, with an overall low positivity rate in newborns. Although the study has limitations, such as the small number of cases and the lack of electron microscope analysis, it is the first attempt to evaluate vertical transmission in Peru. It is concluded that more research is needed to better understand the relationship between COVID-19 infection and complications during pregnancy.

Human microglial cells as a therapeutic target in a neurodevelopmental disease model

Although microglia are macrophages of the central nervous system, their involvement is not limited to immune functions. The roles of microglia during development in humans remain poorly understood due to limited access to fetal tissue. To understand how microglia can impact human neurodevelopment, the methyl-CpG binding protein 2 (MECP2) gene was knocked out in human microglia-like cells (MGLs). Disruption of the MECP2 in MGLs led to transcriptional and functional perturbations, including impaired phagocytosis. The co-culture of healthy MGLs with MECP2-knockout (KO) neurons rescued synaptogenesis defects, suggesting a microglial role in synapse formation. A targeted drug screening identified ADH-503, a CD11b agonist, restored phagocytosis and synapse formation in spheroid-MGL co-cultures, significantly improved disease progression, and increased survival in MeCP2-null mice. These results unveil a MECP2-specific regulation of human microglial phagocytosis and identify a novel therapeutic treatment for MECP2-related conditions.

Peripartum outcomes and immune responses after SARS-CoV-2 infection in the third trimester of pregnancy

BACKGROUND

SARS-CoV-2 infection in pregnant women during the third trimester resulted in overall adverse pregnancy outcomes compared to non-infected controls and a unique humoral and cellular response at delivery. In this study we aimed to assess the impact of SARS-CoV-2 infection on maternal/neonatal peripartum outcomes andimmunological profiles.

METHOD

In this study, we recruited 304 SARS-CoV-2 infected pregnant women and 910 SARS-CoV-2 non-infected pregnant women who were admitted for delivery. Peripartum and neonates' outcomes response to SARS-CoV-2 infection were analyzed. Furthermore, we characterized the antibody and cytokines profile in SARS-CoV-2 infected maternal blood (MB) and cord blood (CB). We also assessed routine laboratory tests and liver function tests in MB before labor. Unpaired T test, Mann-Whitney test and Spearman test were used to analyze the data.

RESULTS

SARS-CoV-2 infected pregnant women were significantly associated with increased risk of adverse pregnancy outcomes, including preterm labor (13.8% vs. 9.5%, p = 0.033) and meconium-stained amniotic fluid (8.9% vs. 5.5%, p = 0.039). The risk of low birth weight (< 2500 g) (10.5% vs. 6.5%, p = 0.021) and Apgar score < 8 at 1-minute (9.2% vs. 5.8%, p = 0.049) significantly increased in newborns from COVID-19 positive mothers than their counterparts. Our results showed that antibodies were increased in adverse-outcome SARS-CoV-2 infected mothers and their neonates, and abnormal proportion of immune cells were detected in SARS-CoV-2 infected mothers. While the immune response showed no difference between adverse-outcome infected pregnant women and normal-outcome infected pregnant women. Thus, SARS-CoV-2 infection during the third trimester of pregnancy induced a unique humoral and cellular response at delivery.

CONCLUSION

SARS-CoV-2 infection closer to delivery could incline to adverse pregnancy outcomes. Therefore, the utmost care is required for SARS-CoV-2 infected pregnant women and their newborns.

TRIAL REGISTRATION

The study protocol was approved by the Institutional Review Board of the First Hospital of Jilin University with the approval code number 23K170-001, and informed consent was obtained from all enrolled patients prior to sample collection.

Neuromotor Behavior of Infants at 3 and 6 Months Prenatally Exposed to SARS-CoV-2: a Brief Report

Prenatal SARS-CoV-2 infection may be a risk factor for neurological impairment. This study describes the neuromotor behavior of infants prenatally exposed to SARS-CoV-2 using gold standard tools for early detection of neurological impairment. Sixteen infants were included in this exploratory longitudinal study. Infants were assessed at 3 months using the Prechtl General Movement Assessment, and at 6 months using the Hammersmith Infant Neurological Examination. Infants might have presented neuromotor limitations at 3 months; however, they progressed to a low-risk outcome of neurological impairment at 6 months.

Antenatal and neonatal exposure to SARS-CoV-2 and children's development: a systematic review and meta-analysis

OBJECTIVES

To conduct a systematic review of the impact of antenatal and neonatal exposure to SARS-CoV-2 on developmental outcomes in preterm and term-born infants.

METHODS

We searched Embase, Emcare, MEDLINE, PsycINFO, Web of Science and grey literature on May 27, 2022 and updated on May 8, 2023. Studies defining exposure with a positive SARS-CoV-2 protein or genetic material, used a contemporaneous non-exposed cohort, and reported developmental outcomes up to 2 years of age were included.

RESULTS

Four out of 828 screened studies were included. Meta-analysis included 815 infants screened for developmental delay (n = 306 exposed; n = 509 non-exposed) between 3- and 11-months of age. Among term-born infants, we did not find an increased risk of delay in communication (odd's ratio: 0.73 (95% CI: 0.24-2.24)), gross motor (1.50 (0.62, 3.62)), fine motor (2.90 (0.58, 14.43)), problem-solving (1.19 (0.54, 2.66)) or personal-social development (1.93 (0.78, 4.75)) in exposed infants. The number of preterm-born infants in the exposed (n = 37) and comparison cohorts (n = 41) were too few to report meaningful comparisons.

CONCLUSION

Evidence regarding the potential impact of antenatal or neonatal exposure to SARS-CoV-2 infection on developmental outcomes in early infancy is limited and inconsistent. Larger cohorts with outcomes beyond the first year of life are needed.

IMPACT

The current evidence examining associations between SARS-CoV-2 exposure during the neonatal period and developmental outcomes in infancy is limited by there being few studies with extremely small sample sizes. Based on sparse data there was no consistent association between antenatal or neonatal exposure to SARS-CoV-2 infection and an adverse impact on developmental outcomes below 12 months of age for babies born preterm or at term. This study highlights that larger cohorts with outcomes assessed beyond the first year are needed to determine the potential longer-term impact of SARS-CoV-2 infection exposure on child development.

Effect of Early pregnancy associated protein-1 on Spike protein and ACE2 interactions: Implications in SARS Cov-2 vertical transmission

INTRODUCTION

Several factors influence transmission of 2019-nCoV from mother to fetus during pregnancy, thus the dynamics of vertical transmission is unclear. The role of cellular protective factors, namely a 90 KDa glycoprotein, Early pregnancy-associated protein (Epap-1), expressed by placental endothelial cells in women during early pregnancy would provide an insight into role of placental factors in virus transmission. Since viral spike protein binding to the ACE2 receptors of the host cells promotes virus invasion in placental tissue, an analysis of effects of Epap-1 on the Spike-ACE2 protein binding was studied.

METHODS

Epap-1 was isolated from MTP placental tissue. Molecular interaction of Epap-1 and variants of the spike was analyzed in silco. The interaction of Epap-1 with Spike and RBD were analyzed using ELISA and immunofluorescence studies.

RESULTS

The results in silico showed an interaction of Epap-1 with S-protein at RBD region involving K417, Y449, Y453, Y456, Y473, Q474, F486, Q498, N501 residues of spike with Y61, F287, I302, N303, N305, S334, N465, G467, N468 residues of Epap-1 leading to interference of S-protein and ACE2 interaction [1]. Further, the interaction is conserved among the variants. The studies in vitro confirm that Epap-1 affects S protein-ACE2 and RBD- ACE2 binding, thus suggesting that during early pregnancy, SARS CoV-2 infection may be protected by Epap-1 protein present in placental tissue. The results were further confirmed by pseudovirus expressing Spike and RBD in an infection assay.

DISCUSSION

Epap-1 interferes with Spike and RBD interaction with ACE2, suggesting a possible mechanism of the antiviral environment during pregnancy.

Endocytosis at the maternal-fetal interface: balancing nutrient transport and pathogen defense

Endocytosis represents a category of regulated active transport mechanisms. These encompass clathrin-dependent and -independent mechanisms, as well as fluid phase micropinocytosis and macropinocytosis, each demonstrating varying degrees of specificity and capacity. Collectively, these mechanisms facilitate the internalization of cargo into cellular vesicles. Pregnancy is one such physiological state during which endocytosis may play critical roles. A successful pregnancy necessitates ongoing communication between maternal and fetal cells at the maternal-fetal interface to ensure immunologic tolerance for the semi-allogenic fetus whilst providing adequate protection against infection from pathogens, such as viruses and bacteria. It also requires transport of nutrients across the maternal-fetal interface, but restriction of potentially harmful chemicals and drugs to allow fetal development. In this context, trogocytosis, a specific form of endocytosis, plays a crucial role in immunological tolerance and infection prevention. Endocytosis is also thought to play a significant role in nutrient and toxin handling at the maternal-fetal interface, though its mechanisms remain less understood. A comprehensive understanding of endocytosis and its mechanisms not only enhances our knowledge of maternal-fetal interactions but is also essential for identifying the pathogenesis of pregnancy pathologies and providing new avenues for therapeutic intervention.

Placental SARS-CoV-2 Infection and Its Implications for Increased Risk of Adverse Pregnancy Outcomes

OBJECTIVE

 Pregnant women are at increased risk of coronavirus disease 2019 (COVID-19). This could be explained through the prism of physiologic and immunologic changes in pregnancy. In addition, certain immunological reactions originate in the placenta in response to viral infections.This study aimed to investigate whether severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) can infect the human placenta and discuss its implications in the pathogenesis of adverse pregnancy outcomes.

STUDY DESIGN

 We conducted a retrospective cohort study in which we collected placental specimens from pregnant women who had a laboratory-confirmed SARS-CoV-2 infection. We performed RNA in situ hybridization assay on formalin-fixed paraffin-embedded tissues to establish the in vivo evidence for placental infectivity by this corona virus. In addition, we infected trophoblast isolated from uninfected term human placenta with SARS-CoV-2 variants to further provide in vitro evidence for such an infectivity.

RESULTS

 There was a total of 21 cases enrolled, which included 5 cases of spontaneous preterm birth (SPTB) and 2 intrauterine fetal demises (IUFDs). Positive staining of positive-sense strand of SARS-CoV-2 virions was detected in 15 placentas including 4 SPTB and both IUFDs. In vitro infection assay demonstrated that SARS-CoV-2 virions were highly capable of infecting both cytotrophoblast and syncytiotrophoblast.

CONCLUSION

 This study implies that placental SARS-CoV-2 infection may be associated with an increased risk of adverse obstetrical outcomes.

KEY POINTS

· SARS-CoV-2 can effectively infect human placenta.. · Such infectivity is confirmed by in vitro experiments.. · Placental SARS-CoV-2 corelates with adverse obstetrical outcomes..

Impact of SARS-CoV-2 infection during pregnancy on the placenta and fetus

Pregnant people and their fetuses are vulnerable to adverse health outcomes from coronavirus 2019 disease (COVID-19) due to infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 has been associated with higher rates of maternal mortality, preterm birth, and stillbirth. While SARS-CoV-2 infection of the placenta and vertical transmission is rare, this may be due to the typically longer time interval between maternal infection and testing of the placenta and neonate. Placental injury is evident in cases of SARS-CoV-2-associated stillbirth with massive perivillous fibrin deposition, chronic histiocytic intervillositis, and trophoblast necrosis. Maternal COVID-19 can also polarize fetal immunity, which may have long-term effects on neurodevelopment. Although the COVID-19 pandemic continues to evolve, the impact of emerging SARS-CoV-2 variants on placental and perinatal injury/mortality remains concerning for maternal and perinatal health. Here, we highlight the impact of COVID-19 on the placenta and fetus and remaining knowledge gaps.

Vertical Transmission of SARS-CoV-2 during Pregnancy: A Prospective Italian Cohort Study

OBJECTIVE

The extent of vertical transmission (VT) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from mothers their fetuses or neonates is still uncertain. We aimed to determine the incidence of VT.

STUDY DESIGN

In this prospective cohort study. All mother diagnosed with SARS-CoV-2 infection at the time of delivery or up to 1 week prior and their neonates, managed in a tertiary referral hospital for pregnancy complicated by coronavirus disease 2019 (COVID-19) in Rome, from April 2 to December 22, 2020, were included. Maternal infection was defined as nasopharyngeal swab test results positive for SARS-CoV-2 reverse transcription-polymerase chain reaction (RT-PCR). Biological samples were collected before, at, and after delivery to test positivity for SARS-CoV-2 RT-PCR and anti-SARS-CoV-2-specific antibodies.

RESULTS

The cohort included 95 women and 96 neonates with documented SARS-CoV-2 test results. Four neonates (4.2%) tested positive. The incidence of VT, according to the guidance criteria for diagnosing perinatal SARS-CoV-2 infection, was 5.2%. Neonatal symptoms were due to prematurity or fetal distress: symptomatic infants had lower median (min-max) gestational age, 38.1 (29.3-40.6) versus 39.3 (33.9-41.9) weeks (p = 0.036), and 1-minute and 5-minute Apgar scores, 9 (3-9) versus 9 (7-10) (p = 0.036) and 10 (6-10) versus 10 (8-10) (p = 0.012), respectively, than asymptomatic infants and needed more frequent assistance in the delivery room (22.2 vs 2.5%; p = 0.008). Only six (7.1%) neonates had anti-SARS-CoV-2-specific antibodies, despite the ongoing maternal infection.

CONCLUSION

The incidence of VT is low as is the detection of specific anti-SARS-CoV-2 antibodies in cord blood when infection is contracted late in pregnancy. This would suggest poor protection of infants against horizontal transmission of the virus.

KEY POINTS

· VT of SARS-CoV-2 from pregnant mothers to fetuses or neonates can be possible.. · In this prospective cohort study, the incidence of VT is found to be 5.2%.. · VT is low but exists..

Vertical transmission of SARS-CoV-2 delta-variant in a preterm infant

BACKGROUND

As SARS-CoV-2 continues to be relevant and cause illnesses, the effect of emerging virus variants on perinatal health remains to be elucidated. It was demonstrated that vertical transmission of SARS-CoV-2 is a relatively rare event in the original SARS-CoV-2 strain. However, very few reports describe vertical transmission related to the delta-variant.

CASE PRESENTATION

We report a case of a preterm male neonate born to a mother with positive SARS-CoV-2 and mild respiratory complications. The neonate was born by cesarean section due to fetal distress. The rupture of the amniotic membrane was at delivery. The neonate had expected prematurity-related complications. His nasopharyngeal swabs for RT-PCR were positive from birth till three weeks of age. RT-ddPCR of the Placenta showed a high load of the SARS-CoV-2 virus with subgenomic viral RNA. RNAscope technique demonstrated both the positive strand of the S gene and the orf1ab negative strand. Detection of subgenomic RNA and the orf1ab negative strand indicats active viral replication in the placenta.

CONCLUSIONS

Our report demonstrates active viral replication of the SARS-CoV-2 delta-variant in the placenta associated with vertical transmission in a preterm infant.

High Transferability of Neutralizing Antibodies against SARS-CoV-2 to Umbilical Cord Blood in Pregnant Women Vaccinated with BNT162b2 XBB.1.5: A Retrospective Cohort Study

BACKGROUND

Coronavirus disease 2019 (COVID-19) can lead to severe respiratory illness, rapid disease progression, and higher rates of intensive care unit admission in pregnant women. Infection during pregnancy is associated with an increased risk of preterm delivery, cesarean section, fetal dysfunction, preeclampsia, and perinatal death. Vertical transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from pregnant women to their fetuses has also been observed. Although severe infections in neonates and infants are rare, newborns can experience serious consequences from COVID-19 due to their suboptimal humoral immune system protection. The amino acids in the structural proteins of SARS-CoV-2 are constantly mutating. Since around January 2023, COVID-19, caused by omicron-type SARS-CoV-2 variants, has been prevalent globally. These variants can evade the immune response triggered by traditional mRNA-based COVID-19 vaccines, such as BNT162b2. Therefore, vaccination with BNT162b2 XBB.1.5, which provides protection against omicron-type SARS-CoV-2 variants, is recommended.

METHODS

This retrospective cohort study included 148 pregnant women who received the BNT162b2 XBB.1.5 vaccine at 30 partner medical institutions from September 2023 to January 2024. We examined the titers of anti-spike glycoprotein SARS-CoV-2 immunoglobin G (IgG) and IgA in the blood and umbilical cord blood obtained from the participants using ELISA.

FINDINGS

Anti-spike glycoprotein SARS-CoV-2 IgG and IgA titers were highest in the blood and cord blood at late gestational age (28-34 weeks). No serious side effects or adverse events were observed in either the pregnant women or their newborns.

INTERPRETATION

Pregnant women who received the BNT162b2 XBB.1.5 vaccine during gestational weeks 28 to 34 had the highest titers of anti-omicron SARS-CoV-2 variant antibodies in their blood. Moreover, these antibodies were transferred to their umbilical cord blood. To validate our findings, large cohort clinical studies involving numerous pregnant women are warranted.

FUNDING

This study was funded by Grants-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (JSPS) and Grants-in-Aid for Medical Research from the Japan Agency for Medical Research and Development (AMED).

Maternal COVID-19 exposure and placental characteristics

INTRODUCTION

The impact of COVID-19 on the placenta is poorly described, particularly among minority women.

MATERIALS AND METHODS

This is a retrospective case-control study. Micro- and macroscopic placental pathologic findings were compared for 15 COVID-19 positive and 36 negative mothers. Cases and controls were frequency matched on gestational age, race, maternal comorbidities, and delivery type. Data from the electronic medical record were supplemented with independent review of microscopic slides.

RESULTS

Placentas from cases and controls were similar except the median distance from the site of the cord insertion to the nearest disk margin was statistically significantly shorter among placentas from COVID-19 positive cases (3.5 versus 6.0 cm, p = 0.006). Case status was not associated with an increased risk of placental pathologies.

CONCLUSION

There are few pathologic differences between placentas of COVID-19 positive and negative mothers. Additional studies are needed to investigate the role of timing of infection.

Host factors of SARS-CoV-2 in infection, pathogenesis, and long-term effects

SARS-CoV-2 is the causative virus of the devastating COVID-19 pandemic that results in an unparalleled global health and economic crisis. Despite unprecedented scientific efforts and therapeutic interventions, the fight against COVID-19 continues as the rapid emergence of different SARS-CoV-2 variants of concern and the increasing challenge of long COVID-19, raising a vast demand to understand the pathomechanisms of COVID-19 and its long-term sequelae and develop therapeutic strategies beyond the virus per se. Notably, in addition to the virus itself, the replication cycle of SARS-CoV-2 and clinical severity of COVID-19 is also governed by host factors. In this review, we therefore comprehensively overview the replication cycle and pathogenesis of SARS-CoV-2 from the perspective of host factors and host-virus interactions. We sequentially outline the pathological implications of molecular interactions between host factors and SARS-CoV-2 in multi-organ and multi-system long COVID-19, and summarize current therapeutic strategies and agents targeting host factors for treating these diseases. This knowledge would be key for the identification of new pathophysiological aspects and mechanisms, and the development of actionable therapeutic targets and strategies for tackling COVID-19 and its sequelae.

Outcomes of SARS-CoV-2 infection in early pregnancy-A systematic review and meta-analysis

INTRODUCTION

Available data on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and pregnancy outcomes mostly refer to women contracting the infection during advanced pregnancy or close to delivery. There is limited information on the association between SARS-CoV-2 infection in early pregnancy and outcomes thereof.

MATERIAL AND METHODS

We aimed to systematically review the maternal, fetal and neonatal outcomes following SARS-CoV-2 infection in early pregnancy, defined as <20 weeks of gestation (PROSPERO Registration 2020 CRD42020177673). Searches were carried out in PubMed, Medline, EMBASE, and Scopus databases from January 2020 until April 2023 and the WHO database of publications on coronavirus disease 2019 (COVID-19) from December 2019 to April 2023. Cohort and case-control studies on COVID-19 occurring in early pregnancy that reported data on maternal, fetal, and neonatal outcomes were included. Case reports and studies reporting only exposure to SARS-CoV-2 or not stratifying outcomes based on gestational age were excluded. Data were extracted in duplicate. Meta-analyses were conducted when appropriate, using R meta (R version 4.0.5).

RESULTS

A total of 18 studies, 12 retrospective and six prospective, were included in this review, reporting on 10 147 SARS-CoV-2-positive women infected in early pregnancy, 9533 neonates, and 180 882 SARS-CoV-2 negative women. The studies had low to moderate risk of bias according to the Newcastle-Ottawa quality assessment Scale. The studies showed significant clinical and methodological heterogeneity. A meta-analysis could be performed only on the outcome miscarriage rate, with a pooled random effect odds ratio of 1.44 (95% confidence interval 0.96-2.18), showing no statistical difference in miscarriage in SARS-CoV-2-infected women. Individual studies reported increased incidences of stillbirth, low birthweight and preterm birth among neonates born to mothers affected by COVID-19 in early pregnancy; however, these results were not consistent among all studies.

CONCLUSIONS

In this comprehensive systematic review of available evidence, we identified no statistically significant adverse association between SARS-CoV-2 infection in early pregnancy (before 20 weeks of gestation) and fetal, neonatal, or maternal outcomes. However, a 44% increase in miscarriage rate is concerning and further studies of larger sample size are needed to confirm or refute our findings.

Genital Dysbiosis and Different Systemic Immune Responses Based on the Trimester of Pregnancy in SARS-CoV-2 Infection

Respiratory infections are common in pregnancy with conflicting evidence supporting their association with neonatal congenital anomalies, especially during the first trimester. We profiled cytokine and chemokine systemic responses in 242 pregnant women and their newborns after SARS-CoV-2 infection, acquired in different trimesters. Also, we tested transplacental IgG passage and maternal vaginal-rectal microbiomes. IgG transplacental passage was evident, especially with infection acquired in the first trimester. G-CSF concentration-involved in immune cell recruitment-decreased in infected women compared to uninfected ones: a beneficial event for the reduction of inflammation but detrimental to ability to fight infections at birth. The later the infection was acquired, the higher the systemic concentration of IL-8, IP-10, and MCP-1, associated with COVID-19 disease severity. All infected women showed dysbiosis of vaginal and rectal microbiomes, compared to uninfected ones. Two newborns tested positive for SARS-CoV-2 within the first 48 h of life. Notably, their mothers had acute infection at delivery. Although respiratory infections in pregnancy are reported to affect babies' health, with SARS-CoV-2 acquired early during gestation this risk seems low because of the maternal immune response. The observed vaginal and rectal dysbiosis could be relevant for neonatal microbiome establishment, although in our series immediate neonatal outcomes were reassuring.

Congenital infectious encephalopathies from the intrapartum period to postnatal life

Congenital infections are a common but often underrecognized cause of fetal brain abnormalities, as well as fetal-neonatal morbidity and mortality, that should be considered by all healthcare professionals providing neurological care to fetuses and newborns. Maternal infection with various pathogens (cytomegalovirus, Toxoplasmosis, Rubella virus, Parvovirus B19, lymphocytic choriomeningitis virus, syphilis, Zika virus, varicella zoster virus) during pregnancy can be transmitted to the developing fetus, which can cause multisystem dysfunction and destructive or malformative central nervous system lesions. These can be recognized on fetal and neonatal imaging, including ultrasound and MRI. Imaging and clinical features often overlap, but some distinguishing features can help identify specific pathogens and guide subsequent testing strategies. Some pathogens can be specifically treated, and others can be managed with targeted interventions or symptomatic therapy based on expected complications. Neurological and neurodevelopmental complications related to congenital infections vary widely and are likely driven by a combination of pathophysiologic factors, alone or in combination. These include direct invasion of the fetal central nervous system by pathogens, inflammation of the maternal-placental-fetal triad in response to infection, and long-term effects of immunogenic and epigenetic changes in the fetus in response to maternal-fetal infection. Congenital infections and their neurodevelopmental impacts should be seen as an issue of public health policy, given that infection and the associated complications disproportionately affect woman and children from low- and middle-income countries and those with lower socio-economic status in high-income countries. Congenital infections may be preventable and treatable, which can improve long-term neurodevelopmental outcomes in children.

Maternal and Newborn Outcomes of SARS-CoV-2/COVID-19 and Pregnancy: Parallels and Contrasts with Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome

Purpose of Review

Our review aims to compare and contrast Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome and SARS-CoV-2/COVID-19's impact on maternal and neonatal outcomes. We have made significant progress in Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome prevention and treatment over the last few decades. Drawing on empirical evidence with past public health crises can offer valuable insights into dealing with current and future pandemics. Therefore, it is imperative to conduct a comparative analysis of the resemblances and disparities existing between Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome and SARS-CoV-2/COVID-19.This research endeavor represents a pioneering and all-encompassing examination, aiming to discern and comprehend the parallels and contrasts in the respective impacts of SARS-CoV-2 and Human Immunodeficiency Virus on pregnancy.

Recent Findings

Based on the current evidence, there is no indication that pregnancy increases women's susceptibility to acquiring Human Immunodeficiency Virus or SARS-CoV-2. Nevertheless, the state of being pregnant was correlated with the worsening of diseases and their progression. Both Human Immunodeficiency Virus and SARS-CoV-2 pose increased risks of maternal mortality and several obstetric complications, including premature birth and pre-eclampsia. While the vertical transmission of Human Immunodeficiency Virus is well-established, a comprehensive understanding of the vertical transmission of SARS-CoV-2 remains elusive, emphasizing the need for further investigations. Initial data suggest low SARS-CoV-2 vertical transmission rates in the setting of proper preventative interventions and universal screening. A cesarean delivery could reduce the risk of mother-to-child transmission in Human Immunodeficiency Virus-infected women with high viral loads or poor adherence to antiretroviral therapy (ART). However, it did not offer additional protection for Human Immunodeficiency Virus-infected women who adhered to Adherence to Antiretroviral Therapy or those with COVID-19. Human Immunodeficiency Virus and SARS-CoV-2 were linked to neonatal complications such as stillbirth, low birth weight, and neonatal intensive care unit (ICU) admissions. The universal testing of both pregnant patients and neonates is an effective strategy to prevent the spread and complications of both Human Immunodeficiency Virus and SARS-CoV-2. Human Immunodeficiency Virus control largely relies on preventing vertical transmission and medications during pregnancy and postpartum, whereas safety behaviors and vaccines have proven effective in preventing SARS-CoV-2 vertical transmissions.

Summary

This review aims to compare and contrast the impact of Human Immunodeficiency Virus and SARS-CoV-2 on pregnancy outcomes, vertical transmissions, delivery modalities, neonatal outcomes, and clinical management. SARS-CoV-2 and Human Immunodeficiency Virus were associated with significant obstetric-related complications, making close clinical monitoring and preparation essential. Integration of SARS-CoV-2/COVID-19 management with reproductive health services is crucial to ensuring maternal and neonatal outcomes. Our review is not only the first to establish a groundwork for the current state of knowledge and its clinical implications on this topic, but it also sheds new insights for future research directions.Comparing Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome and SARS-CoV-2 in terms of their impact on maternal and neonatal outcomes provides valuable insights despite their differences. Leveraging Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome research can help understand SARS-CoV-2 effects on pregnancy. Both infections pose risks to pregnant individuals and their fetuses, leading to increased maternal mortality and complications. Identifying common patterns and risk factors can improve clinical management for pregnant individuals with SARS-CoV-2. While a direct observational study for this comparison may not be feasible, comparing with Human Immunodeficiency Virus offers an ethical and practical approach. However, specific studies on SARS-CoV-2 are still necessary to gather detailed data on maternal and fetal outcomes.

Evidence of Placental Villous Inflammation and Apoptosis in Third-Trimester Symptomatic SARS-CoV-2 Maternal Infection

PURPOSE

In view of conflicting reports on the ability of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) to infect placental tissue, this study aimed to further evaluate the impact of inflammation and placental damage from symptomatic third-trimester maternal COVID-19 infection.

MATERIALS AND METHODS

This case-control study included 32 placenta samples each from symptomatic COVID-19 pregnancy and normal non-COVID-19 pregnancy. The villous placental area's inflammatory expression [angiotensin converting enzyme-2 (ACE-2), transmembrane protease serine-2 (TMPRSS2), interferon-γ (IFN-γ), interleukin-6 (IL-6), and SARS-CoV-2 spike protein] and apoptotic rate were examined using immunohistochemistry and Terminal deoxynucleotidyl transferase dUTP Nick-End Labeling (TUNEL) assay. Comparison and correlation analysis were used based on COVID-19 infection, placental SARS-CoV-2 spike protein evidence, and maternal severity status.

RESULTS

Higher expressions of TMPRSS2, IFN-γ, and trophoblast apoptotic rate were observed in the COVID-19 group (p<0.001), whereas ACE-2 and IL-6 expressions were not significantly different from the control group (p>0.05). Additionally, SARS-CoV-2 spike protein was detected in 8 (25%) placental samples of COVID-19 pregnancy. COVID-19 subgroup analysis revealed increased IFN-γ, trophoblast, and stromal apoptosis (p<0.01). Moreover, the results of the current study revealed no correlation between maternal COVID-19 severity and placental inflammation as well as the apoptotic process.

CONCLUSION

The presence of SARS-CoV-2 spike protein as well as altered inflammatory and apoptotic processes may indicate the presence of placental disturbance in third-trimester maternal COVID-19 infection. The lack of correlation between placental disruption and maternal severity status suggests the need for more research to understand the infection process and any potential long-term impacts on all offsprings born to COVID-19-infected pregnant women.

Possibility of intrauterine transmission from mother to fetus/newborn: Systematic review and meta-analysis of diagnostic methods to detect SARS-CoV-2 infection

Several studies have reported vertical transmission of SARS-CoV-2; however, information regarding intrauterine transmission based on diagnostic methods to detect SARS-CoV-2 infection is scarce. A systematic review and meta-analysis was conducted to identify and explore the studies that attempt to ascertain the possibility of intrauterine transmission of SARS-CoV-2 infection according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) statement. The results demonstrate that SARS-CoV-2 can be transmitted intrauterine, as detected by clinical manifestations (1.00, 95 % CI: 1.00 - 1.00, 0.51, 95 % CI: 0.22 - 0.80), imaging (0.50, 95 % CI: 0.24 - 0.76, 0.03, 95 % CI: 0.00 - 0.17), molecular (1. 00, 95 % CI: 1.00 - 1.00, 0.92, 95 % CI: 0.77 - 1.00), immunological (0.32, 95 % CI: 0.10 - 0.57, 0.34, 95 % CI: 0.11 - 0.61), and histological approaches (0.79, 95 % CI: 0.52 - 0.98) in maternal and fetal/neonatal specimens, respectively. The possibility of intrauterine transmission of SARS-CoV-2 from mother to fetus/newborn was 41 % (95 % CI 0.37 - 0.45). We might confirm/verify the intrauterine transmission of SARS-CoCV-2 from mother to fetus/newborn.

Mendelian randomization supports genetic liability to hospitalization for COVID-19 as a risk factor of pre-eclampsia

Background

Pre-eclampsia and eclampsia are among the major threats to pregnant women and fetuses, but they can be mitigated by prevention and early screening. Existing observational research presents conflicting evidence regarding the causal effects of coronavirus disease 2019 (COVID-19) on pre-eclampsia risk. Through Mendelian randomization (MR), this study aims to investigate the causal effect of three COVID-19 severity phenotypes on the risk of pre-eclampsia and eclampsia to provide more rigorous evidence.

Methods

Two-sample MR was utilized to examine causal effects. Summary-level data from genome-wide association studies (GWAS) of individuals of European ancestry were acquired from the GWAS catalog and FinnGen databases. Single-nucleotide polymorphisms associated with COVID-19 traits at p < 5 × -8 were obtained and pruned for linkage disequilibrium to generate instrumental variables for COVID-19. Inverse variance weighted estimates were used as the primary MR results, with weighted median and MR-Egger as auxiliary analyses. The robustness of the MR findings was also evaluated through sensitivity analyses. Bonferroni correction was applied to primary results, with a p < 0.0083 considered significant evidence and a p within 0.083-0.05 considered suggestive evidence.

Results

Critical ill COVID-19 [defined as hospitalization for COVID-19 with either a death outcome or respiratory support, OR (95% CI): 1.17 (1.03-1.33), p = 0.020] and hospitalized COVID-19 [defined as hospitalization for COVID-19, OR (95% CI): 1.10 (1.01-1.19), p = 0.026] demonstrated suggestive causal effects on pre-eclampsia, while general severe acute respiratory syndrome coronavirus 2 infection did not exhibit a significant causal effect on pre-eclampsia. None of the three COVID-19 severity phenotypes exhibited a significant causal effect on eclampsia.

Conclusions

Our investigation demonstrates a suggestive causal effect of genetic susceptibility to critical ill COVID-19 and hospitalized COVID-19 on pre-eclampsia. The COVID-19 severity exhibited a suggestive positive dose-response relationship with the risk of pre-eclampsia. Augmented attention should be paid to pregnant women hospitalized for COVID-19, especially those needing respiratory support.

Gestational diabetes mellitus in the era of COVID-19: Challenges and opportunities

BACKGROUND AND AIMS

The impact of the coronavirus disease 2019 (COVID-19) pandemic on pregnant women, especially those with gestational diabetes mellitus (GDM), has yet to be fully understood. This review aims to examine the interaction between GDM and COVID-19 and to elucidate the pathophysiological mechanisms underlying the comorbidity of these two conditions.

METHODS

We performed a systematic literature search using the databases of PubMed, Embase, and Web of Science with appropriate keywords and MeSH terms. Our analysis included studies published up to January 26, 2023.

RESULTS

Despite distinct clinical manifestations, GDM and COVID-19 share common pathophysiological characteristics, which involve complex interactions across multiple organs and systems. On the one hand, infection with severe acute respiratory syndrome coronavirus 2 may target the pancreas and placenta, resulting in β-cell dysfunction and insulin resistance in pregnant women. On the other hand, the hormonal and inflammatory changes that occur during pregnancy could also increase the risk of severe COVID-19 in mothers with GDM. Personalized management and close monitoring are crucial for treating pregnant women with both GDM and COVID-19.

CONCLUSIONS

A comprehensive understanding of the interactive mechanisms of GDM and COVID-19 would facilitate the initiation of more targeted preventive and therapeutic strategies. There is an urgent need to develop novel biomarkers and functional indicators for early identification and intervention of these conditions.

SARS-CoV-2-Placental effects and association with stillbirth

SARS-CoV-2 has had a significant impact on pregnancy outcomes due to the effects of the virus and the altered healthcare environment. Stillbirth has been relatively hidden during the COVID-19 pandemic, but a clear link between SARS-CoV-2 and poor fetal outcome emerged in the Alpha and Delta waves. A small minority of women/birthing people who contracted COVID-19 developed SARS-CoV-2 placentitis. In many reported cases this was linked to intrauterine fetal death, although there are cases of delivery just before imminent fetal demise and we shall discuss how some cases are sub-clinical. What is surprising, is that SARS-CoV-2 placentitis is often not associated with severe maternal COVID-19 infection and this makes it difficult to predict. The worst outcomes seem to be with diffuse placental disease which occurs within 21 days of COVID-19 diagnosis. Poor outcomes are often pre-dated by reduced fetal movements but are not associated with ultrasound changes. In some cases, there has also been maternal thrombocytopenia, or coagulation abnormalities, which may provide a clue as to which pregnancies are at risk of fetal demise if a further variant of concern is to emerge. In future, multidisciplinary collaboration and cross-boundary working must be prioritised, to identify quickly such a phenomenon and provide clinicians with clear guidance for reducing fetal death and associated poor outcomes. While we wait to see if COVID-19 brings a future variant of concern, we must focus on appropriate future management of women who have had SARS-CoV-2 placentitis. As a placental condition with an infectious aetiology, SARS-CoV-placentitis is unlikely to recur in a subsequent pregnancy and thus a measured approach to subsequent pregnancy management is needed.

The psychosocial experiences of pregnant women in the early stages of the COVID-19 pandemic: A retrospective qualitative study

BACKGROUND

Pregnant women are among the most vulnerable and suffer the most during pandemics, according to earlier studies. Pregnant women had to seek healthcare for both themselves and their unborn child(ren) in the wake of the COVID-19 pandemic, which was unprecedented. Pregnant women's psychosocial experiences during pandemics are crucial since they both directly and indirectly affect the course of pregnancy and childbirth. The study therefore sought to explore the psychosocial experiences of pregnant women during the COVID-19 pandemic.

METHODS

In this retrospective qualitative study, 15 nursing mothers who were attending a postnatal clinic at the Kwame Nkrumah University of Science and Technology (KNUST) hospital in Ghana were recruited. Individual interviews were conducted with mothers who were pregnant between March and December 2020. The audio-recorded interviews were transcribed verbatim and inductively analysed into themes.

RESULTS

Nursing mothers were aged 25-30 years and had infants ranging from 5 months to 15 months. Thirteen (13) were married and two were single. Two (2) major themes and five (5) subthemes emerged from the study. The unpleasant feelings connected to the potential for contracting COVID-19 and experiencing stress were described by the theme, "Fear and Stress". Participants' social experiences (support from significant others), alterations in daily routine and the economic impact because of the pandemic were presented as the "Socioeconomic impact".

CONCLUSION

Pregnant women go through several challenges during pregnancy such as perceived stress and anxiety. These are likely to heighten during a pandemic, as presented in the study. They therefore need emotional and psychosocial support in such uncertain times to improve outcomes of pregnancy.

Vertical transmission of SARS-CoV-2 - data from the German COVID-19 related obstetric and neonatal outcome study (CRONOS)

OBJECTIVES

We aimed to determine the frequency of SARS-CoV-2 positivity in newborns born to mothers with peripartum SARS-CoV-2 infection in a German cohort, to identify potential risk factors associated with neonatal SARS-CoV-2 infection, and to present short-term outcomes of newborns with vertical transmission of SARS-CoV-2.

METHODS

Data on women with SARS-CoV-2 infection occurring anytime during their pregnancy was gathered prospectively within the CRONOS registry. From April 2020 to February 2023 a total of 8,540 women had been registered. The timing and the probability of mother-to-child transmission in neonates born to women with perinatal SARS-CoV-2 infection were classified using the WHO classification system. The severity of maternal infection, maternal vaccination status, type of dominant virus, and perinatal outcome parameters were analyzed as potential risk factors for neonatal SARS-CoV-2 infection.

RESULTS

6.3 % resp. 42.9 % of tested newborns and stillbirths were SARS-CoV-2 positive. 2.1 % of newborns with confirmed and possible SARS-CoV-2 infection were identified. Severe maternal COVID-19 (odds ratio 4.4, 95 % confidence interval 1.8-11.1) and maternal infection with the Delta virus (OR 3.2, 1.4-7.7) were associated with neonatal SARS-CoV-2 infection. Newborns with a confirmed or possible infection were significantly more often admitted to the NICU (65.2 % neonatal infection vs. 27.5 % non, p<0.001).

CONCLUSIONS

The rate of neonatal SARS-CoV-2 positivity was higher in our cohort than previously reported, neonatal SARS-CoV-2 infections were rare. Our data emphasizes confirmative testing should be performed in newborns of SARS-CoV-2 infected mothers to identify neonatal SARS-CoV-2 infection as an underlying pathology leading to NICU admission.

Vertical Transmission of SARS-CoV-2-Specific Antibodies and Cytokine Profiles in Pregnancy

Despite intensive characterization of immune responses after COVID-19 infection and vaccination, research examining protective correlates of vertical transmission in pregnancy are limited. Herein, we profiled humoral and cellular characteristics in pregnant women infected or vaccinated at different trimesters and in their corresponding newborns. We noted a significant correlation between spike S1-specific IgG antibody and its RBD-ACE2 blocking activity (receptor-binding domain-human angiotensin-converting enzyme 2) in maternal and cord plasma (P < .001, R > 0.90). Blocking activity of spike S1-specific IgG was significantly higher in pregnant women infected during the third trimester than the first and second trimesters. Elevated levels of 28 cytokines/chemokines, mainly proinflammatory, were noted in maternal plasma with infection at delivery, while cord plasma with maternal infection 2 weeks before delivery exhibited the emergence of anti-inflammatory cytokines. Our data support vertical transmission of protective SARS-CoV-2-specific antibodies. This vertical antibody transmission and the presence of anti-inflammatory cytokines in cord blood may offset adverse outcomes of inflammation in exposed newborns.

Analysis of the transplacental transmission of SARS CoV-2 virus and antibody transfer according to the gestational age at maternal infection

To quantify transplacental transmission of SARS-CoV-2 virus and antibody transfer in pregnant women and their newborns according to the gestational age at maternal infection. A prospective observational multicenter study including pregnant women with a positive RT-PCR or a positive serology for SARS-CoV-2 and compatible symptoms, from April to December 2020, in 11 French maternities. The study was designed to obtain a systematic collection of mother-infant dyad's samples at birth. SARS-CoV-2 viral load was measured by RT-PCR. IgG and IgM antibodies against the SARS-CoV-2 spike protein were measured by enzyme-linked immunosorbent assay. Antibody concentrations and transplacental transfer ratios were analyzed according to the gestational age at maternal infection. The primary outcome was the rate of SARS CoV-2 materno-fetal transmission at birth. The secondary outcome was the quantification of materno-fetal antibody transfer. Maternal and neonatal outcomes at birth were additionally assessed. Among 165 dyads enrolled, one congenital infection was confirmed {n = 1 (0.63%) IC95% [0.02%; 3.48%]}. The average placental IgG antibody transfer ratio was 1.27 (IC 95% [0.69-2.89]). The transfer ratio increased with increasing time between the onset of maternal infection and delivery (P Value = 0.0001). Maternal and neonatal outcomes were reassuring. We confirmed the very low rate of SARS-CoV-2 transplacental transmission (< 1%). Maternal antibody transfer to the fetus was more efficient when the infection occurred during the first and second trimester of pregnancy.

Long-Term Outcome of Neonates and Infants whose Mothers Tested Positive for SARS-CoV-2 during Pregnancy - a Pilot of the Post-CRONOS Project

OBJECTIVE

Long-term effects on infants of mothers with SARS-CoV-2 infection during pregnancy are increasingly discussed in the literature. Besides potential neurodevelopment impairments after intrauterine SARS-CoV-2 exposure, there might be differences in the postnatal pediatric care of those children, like the timing of preventive medical examinations (PME) or vaccinations. In this first national long-term follow-up study of women included in the CRONOS registry, we describe maternal impressions of their child´s development and the prevalence of regulatory disorders, and we analyze the timing of PMEs and vaccinations.

METHODS

773 women who were enrolled between April 3, 2020, and August 24, 2021, in the CRONOS registry were eligible to be contacted by the study coordinators and asked to fill out a web-based questionnaire.

RESULTS

110/773 (14%) women completed the questionnaire. Their children were between the ages of 12 and 31 months (median 20 months). All mothers were satisfied with their child´s development, milestones were achieved in a timely fashion. The reported prevalence for excessive crying, sleeping, and feeding disorders was 11%, 18-32%, and 7%, respectively. PMEs were mostly not delayed, but only 54% of infants received their first vaccination within their first 60 days of life.

DISCUSSION

  In summary, our exploratory findings suggest that developmental milestones in infancy are reached in time after maternal SARS-CoV-2 infection during pregnancy. However, there are effects on the implementation of PMEs and vaccinations. EINFüHRUNG: In der Literatur werden zunehmend potenzielle Langzeitfolgen für Säuglinge nach intrauteriner SARS-CoV-2-Exposition diskutiert. Neben möglichen Beeinträchtigungen der neurologischen Entwicklung können Unterschiede in der pädiatrischen postnatalen Betreuung bei diesen Kindern z. B. bei der Durchführung von Vorsorgeuntersuchungen (sog. U´s) oder Impfungen bestehen. In dieser ersten nationalen Langzeit-Follow-up-Studie aus dem CRONOS-Register beschreiben wir mütterliche Eindrücke zur Entwicklung ihres Kindes, sowie die Prävalenz von Regulationsstörungen. Wir analysieren den Zeitpunkt von U´s und Impfungen.

METHODEN

773 Frauen, die zwischen dem 03.04.2020 und dem 24.08.2021 in CRONOS aufgenommen wurden, wurden von den Studienkoordinatoren kontaktiert und gebeten, einen webbasierten Fragebogen auszufüllen.

ERGEBNISSE

110/773 (14%) Frauen füllten den Fragebogen aus, ihre Kinder waren zwischen 12 und 31 Monate alt (Median 20 Monate). Alle Mütter waren mit der Entwicklung ihres Kindes zufrieden, Meilensteine der Entwicklung wurden zeitgerecht erreicht. Die berichtete Prävalenz für exzessives Schreien, Schlaf- und Fütterstörungen betrug 11%, 18-32% bzw. 7%. U´s wurden meist zeitgerecht durchgeführt, aber nur 54% der Säuglinge erhielten ihre erste Impfung innerhalb der ersten 60 Lebenstage.

DISKUSSION

Zusammenfassend deuten unsere explorativen Ergebnisse darauf hin, dass Entwicklungsmeilensteine im Säuglingsalter nach mütterlicher SARS-CoV-2-Infektion in der Schwangerschaft rechtzeitig erreicht werden. Es zeigen sich jedoch Auswirkungen auf die Durchführung von Vorsorgen und Impfungen.

Maternal COVID-19 infection and intrauterine fetal death: Impact on the placenta and fetus

BACKGROUND

Placental damage due to viral infections increases risk of adverse perinatal outcomes. Histopathologic examination of placenta can provide information regarding association between infection and outcome. There is paucity of data describing placental pathology with respect to intrauterine fetal death (IUFD) in pregnant mothers affected with COVID-19.

METHODS

4 fetuses and 10 placentas, including one twin placenta from 9 women with history of IUFD and SARS-CoV-2 infection underwent evaluation. These findings were contrasted with 3 fetuses and 21 gestational age matched placentas from non-infected women with history of IUFD.

RESULTS

Extensive gross placental lesions, mixture of histologic features (maternal/ fetal vascular malperfusion) and isolated cases of massive perivillous fibrin depositon and chronic intervillositis were observed in COVID-IUFD group. There were no distinguishing histologic findings when compared to control. Three fetuses showed signs of intraventricular/intraparenchymal hemorrhage in autopsy.

CONCLUSION

These findings demonstrate that IUFD does not correspond with maternal symptoms and lacks distinctive lesion. However, there was significant placental damage which developed rapidly. These results show that SARS-CoV-2 infection results in rapid placental deterioration and fetal death. This information can be used to educate infected mothers and remind medical professionals, value of monitoring placental function especially following diagnosis of infection.

Maternal SARS-CoV-2 infection in pregnancy disrupts gene expression in Hofbauer cells with limited impact on cytotrophoblasts

BACKGROUND

Hofbauer cells (HBCs) and cytotrophoblasts (CTBs) are major cell populations in placenta. The indirect impact of maternal SARS-CoV-2 disease on these cells that are not directly infected has not been extensively studied. Herein, we profiled gene expression in HBCs and CTBs isolated from placentae of recovered pregnant subjects infected with SARS-CoV-2 during all trimesters of pregnancy, placentae from subjects with active infection, SARS-CoV-2 vaccinated subjects, and those who were unexposed to the virus.

METHODS

Placentae were collected within 4 h post-delivery and membrane-free tissues were enzymatically digested for the isolation of HBCs and CTBs. RNA extracted from HBCs and CTBs were sequenced using 150bp paired-end reads. Differentially expressed genes (DEGs) were identified by DESeq2 package in R and enriched in GO Biological Processes, KEGG Pathway, Reactome Gene Sets, Hallmark Gene Sets, and Canonical Pathways. Protein-protein interactions among the DEGs were modelled using STRING and BioGrid.

RESULTS

Pregnant subjects (n = 30) were recruited and categorized into six groups: infected with SARS-CoV-2 in i) the first (1T, n = 4), ii) second (2T, n = 5), iii) third (3T, n = 5) trimester, iv) tested positive at delivery (Delivery, n = 5), v) never infected (Control, n = 6), and vi) fully mRNA-vaccinated by delivery (Vaccinated, n = 5). Compared to the Control group, gene expression analysis showed that HBCs from infected subjects had significantly altered gene expression profiles, with the 2T group having the highest number of DEGs (1,696), followed by 3T and 1T groups (1,656 and 958 DEGs, respectively). These DEGs were enriched for pathways involved in immune regulation for host defense, including production of cytokines, chemokines, antimicrobial proteins, ribosomal assembly, neutrophil degranulation inflammation, morphogenesis, and cell migration/adhesion. Protein-protein interaction analysis mapped these DEGs with oxidative phosphorylation, translation, extracellular matrix organization, and type I interferon signaling. Only 95, 23, and 8 DEGs were identified in CTBs of 1T, 2T, and 3T groups, respectively. Similarly, 11 and 3 DEGs were identified in CTBs and HBCs of vaccinated subjects, respectively. Reassuringly, mRNA vaccination did not induce an inflammatory response in placental cells.

CONCLUSIONS

Our studies demonstrate a significant impact of indirect SARS-CoV-2 infection on gene expression of inner mesenchymal HBCs, with limited effect on lining CTB cells isolated from pregnant subjects infected and recovered from SARS-CoV-2. The pathways associated with these DEGs identify potential targets for therapeutic intervention.

[SARS-CoV-2 Infection in Pregnancy and Incidence of Congenital Malformations - is there a Correlation? Analysis of 8032 Pregnancies from the CRONOS Registry]

BACKGROUND

Based on single case reports, the COVID-19 Related Obstetric and Neonatal Outcome Study (CRONOS) registry, sponsored by the German Society for Perinatal Medicine (DGPM), investigated the likelihood that SARS-CoV-2 infections of the mother in (early) pregnancy cause embryopathies and/or fetopathies.

MATERIAL/METHODS

The CRONOS registry enrolled a total of 8032 women with confirmed SARS-CoV-2 infection during pregnancy at more than 130 participating hospitals from April 2020 to February 2023. Both maternal and fetal data were documented and the anonymized multicenter data were analyzed.

RESULTS

Of 7142 fully documented pregnancies (including postnatal data), 140 showed congenital malformations. 8.57% of the mothers had had a SARS-CoV-2-infection in the 1st trimester and 36.43% in the 2nd trimester. In 66 cases with congenital malformations (47.14%), the malformation was only detected after the diagnosis of a maternal SARS-CoV-2 infection. The overall prevalence of congenital malformations in this cohort was 1.96%, compared to a prevalence of 2.39% reported in the EUROCAT (European network of population-based registries for the epidemiological surveillance of congenital anomalies) pre-pandemic registry between 2017-2019.

DISCUSSION

Our multicenter data argue against a link between maternal SARS-CoV-2 infection in early pregnancy and congenital malformation.

Covid-19 during Pregnancy - Histopathological Lesions of the Placenta

INTRODUCTION

Pregnant women and their offspring represented a vulnerable patient collective during the Covid-19 pandemic. Beyond the direct effect of SARS-CoV-2 via vertical transmission, an indirect impact on the fetus can occur through placental lesions deteriorating placental villous function. We performed a histopathological analysis of placentas of parturients with SARS-CoV-2 compared to healthy controls.

METHODS AND MATERIALS

Between February 2022 and July 2022 we conducted a prospective case-control study analyzing placental specimens of parturients with SARS-CoV-2 infection compared to specimens of placentas of healthy controls. Patient history, Covid-19-specific symptoms, and obstetric outcomes were recorded. Statistical analysis was performed.

RESULTS

During the observation period 71 patients were included with a gestational age 37 1/7-41 5/7 weeks. Thirty-six patients presented with SARS-CoV-2 infection. The control group consisted of 35 patients and showed no placental abnormalities. Among SARS-CoV-2-positive parturients, 66.7% of placentas of the case group showed histopathological abnormalities classified as vascular or inflammatory abnormalities. 22.2% of placentas showed acute ischemic infarction areas. 8.3% of placentas showed subchorionic layered thrombi. There was one case of severe acute subchorionitis. SARS-CoV-2 increased the risk of placental lesions significantly (OR 3.000, CI 1.890-4.762, p=0.0001). Placental lesions had no significant impact on perinatal acidosis (OR 0.455, CI 0.044-4.667, p=0.498) or number of cesarean sections (OR 2.314, CI 0.717-7.473, p=0.156).

CONCLUSION

SARS-CoV-2 infection during labor and delivery increased the risk of adverse outcomes. Histopathological analysis indicated that the placenta as a maternal-fetal interface was affected by SARS-CoV-2, leading to systemic vasculopathy and inflammation.

Impact of respiratory viral infections during pregnancy on the neurological outcomes of the newborn: current knowledge

Brain development is a complex process that begins during pregnancy, and the events occurring during this sensitive period can affect the offspring's neurodevelopmental outcomes. Respiratory viral infections are frequently reported in pregnant women, and, in the last few decades, they have been related to numerous neuropsychiatric sequelae. Respiratory viruses can disrupt brain development by directly invading the fetal circulation through vertical transmission or inducing neuroinflammation through the maternal immune activation and production of inflammatory cytokines. Influenza virus gestational infection has been consistently associated with psychotic disorders, such as schizophrenia and autism spectrum disorder, while the recent pandemic raised some concerns regarding the effects of severe acute respiratory syndrome coronavirus 2 on neurodevelopmental outcomes of children born to affected mothers. In addition, emerging evidence supports the possible role of respiratory syncytial virus infection as a risk factor for adverse neuropsychiatric consequences. Understanding the mechanisms underlying developmental dysfunction allows for improving preventive strategies, early diagnosis, and prompt interventions.

Diffusion-sensitized magnetic resonance imaging highlights placental microstructural damage in patients with previous SARS-CoV-2 pregnancy infection

INTRODUCTION

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been a major global health problem since December 2019. This work aimed to investigate whether pregnant women's mild and moderate SARS-CoV-2 infection was associated with microstructural and vascular changes in the placenta observable in vivo by Intravoxel Incoherent Motion (IVIM) at different gestational ages (GA).

METHODS

This was a retrospective, nested case-control of pregnant women during the SARS-CoV-2 pandemic (COVID-19 group, n = 14) compared to pre-pandemic healthy controls (n = 19). MRI IVIM protocol at 1.5T was constituted of diffusion-weighted (DW) images with TR/TE = 3100/76 ms and 10 b-values (0,10,30,50,75,100,200,400,700,1000s/mm2). Differences between IVIM parameters D (diffusion), and f (fractional perfusion) quantified in the two groups were evaluated using the ANOVA test with Bonferroni correction and linear correlation between IVIM metrics and GA, COVID-19 duration, the delay time between a positive SARS-CoV-2 test and MRI examination (delay-time exam+) was studied by Pearson-test.

RESULTS

D was significantly higher in the COVID-19 placentas compared to that of the age-matched healthy group (p < 0.04 in fetal and p < 0.007 in maternal site). No significant difference between f values was found in the two groups suggesting no-specific microstructural damage with no perfusion alteration (potentially quantified by f) in mild/moderate SARS-Cov-2 placentas. A significant negative correlation was found between D and GA in the COVID-19 placentas whereas no significant correlation was found in the control placentas reflecting a possible accelerated senescence process due to COVID-19.

DISCUSSION

We report impaired microstructural placental development during pregnancy and the absence of perfusion-IVIM parameter changes that may indicate no perfusion changing through microvessels and microvilli in the placentas of pregnancies with mild/moderate SARS-Cov-2 after reaching negativity.

Likely Vertical Transmission of Neonatal SARS CoV-2 Infection

Maternal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can affect placental function, but the possibility of intrauterine transmission has been debated. Several authors have published inclusion criteria for vertical transmission, but few reports exist that are able to meet the suggested requirements. Despite the fact that the majority of fetuses born to infected mothers do well, others become critically ill. We present a case of likely intrauterine transmission of a neonate born to a mother who was recently symptomatic with a positive SARS CoV-2 polymerase chain reaction (PCR). The parturient complained of decreased fetal movement and presented at 31 2/7 weeks' gestation with a biophysical profile score of 2/10 and required an emergency cesarean delivery. The neonate went on to develop severe leukopenia with signs of sepsis with a positive SARS CoV-2 PCR on day 4 of life and an otherwise pan-negative workup. Meeting criteria for transplacental transmission requires timely collection of several diagnostic studies that are not standard of care. Further research is needed to support the notion that intrauterine/transplacental infection is possible. Collection swabs should be obtained soon after delivery to help diagnose neonatal infection because early diagnosis is crucial to help identify opportunities for intervention.

Massive perivillous fibrin deposition: Diagnosis, obstetrical features, and treatment

MPVFD (Massive perivillous fibrin deposition) is placental lesion characterized by extensive massive deposits of fibrin in the intervillous space, extending over at least 25 % of the placental volume. Currently, this pathology can only be detected through histopathological examination of the placenta after a pregnancy has ended. The underlying mechanisms are poorly studied, there is no biomarker available for the diagnosis of MPVFD and treatment protocols are experimental and still lacking. The objective of this study is to systematically review the literature on the associated clinicopathologic features, treatment, and prognosis of MPVFD. We ended up with 17 studies, of these 12 studies were considered relevant for this article and included in the final analysis. All studies reporting MPVFD are retrospective. MPVFD is associated with recurrent miscarriage, intra uterine fetal death (IUFD), intra uterine growth restriction (IUGR) and preterm delivery. The prevalence in pregnancies with a delivery after 22 weeks of gestation was at 1.1 % and even higher to 2.7 % in recurrent early miscarriages. The reported risk of fetal death in MPVFD ranges mainly from 15 to 80 %. Preterm delivery is spontaneous in 50 to 70 % of cases and induced by of a severe intrauterine growth restriction (IUGR) in 30 to 50 % of cases depending on the study. Its causes and treatment are still poorly understood, although several avenues have been explored. This review summarizes current understanding of the prevalence, diagnostic features, clinical consequences, immune pathology, and potential prophylaxis against recurrence in this chronic inflammatory placental syndrome.

Mechanisms of SARS-CoV-2 Placental Transmission

The widespread occurrence of SARS-CoV-2 infections and the diverse range of symptoms have placed significant strain on healthcare systems worldwide. Pregnancy has also been affected by COVID-19, with an increased risk of complications and unfavorable outcomes for expectant mothers. Multiple studies indicate that SARS-CoV-2 can infiltrate the placenta, breach its protective barrier, and infect the fetus. Although the precise mechanisms of intrauterine transmission remain unclear, factors such as perinatal infection, macrophages, sexual intercourse, and the virus' interaction with host angiotensin-converting enzyme 2 (ACE2) and neuropilin-1 (NRP-1) proteins appear to play a role in this process. The integrity of the placental barrier fluctuates throughout pregnancy and appears to influence the likelihood of fetal transmission. The expression of placental cell receptors, like ACE2, changes during pregnancy and in response to placental damage. However, due to the consistent presence of others, such as NRP-1, SARS-CoV-2 may potentially enter the fetus at different stages of pregnancy. NRP-1 is also found in macrophages, implicating maternal macrophages and Hofbauer cells as potential routes for viral transmission. Our current understanding of SARS-CoV-2's vertical transmission pathways remains limited. Some researchers question the ACE2-associated transmission model due to the relatively low expression of ACE2 in the placenta. Existing studies investigating perinatal transmission and the impact of sexual intercourse have either involved small sample sizes or lacked statistical significance. This review aims to explore the current state of knowledge regarding the potential mechanisms of COVID-19 vertical transmission, identifying areas where further research is needed to fill the gaps in our understanding.

Effects of SARS-CoV-2 gestational exposure and risk factors on neurodevelopment until 12 months: A prospective cohort study in Brazil

BACKGROUND

The effects of SARS-CoV-2 gestational exposure on child development remain inconclusive.

AIMS

To analyze the effects of SARS-CoV-2 gestational exposure on neurodevelopment until 12 months.

STUDY DESIGN

Prospective cohort study conducted in five municipalities in Southeast Brazil from August 2021 to September 2022.

SUBJECTS

Infants were recruited from a serological survey performed during neonatal screening and followed up to 12 months old. We included 224 infants exposed to SARS-CoV-2 during pregnancy and 225 non-exposed, according to the serology results of the newborn as well as their mothers and the maternal antenatal RT-PCR results.

OUTCOME MEASURES

Developmental assessments were performed at 6 and 12 months using the Survey of Wellbeing of Young Children-Brazilian Version (SWYC-BR). Children with suspected developmental delay (SDD) at 6 and 12 months were considered at high risk for developmental delay (HRDD). Additionally, risk factors associated with SDD were examined.

RESULTS

There were 111 children identified with SDD and 52 with HRDD. SARS-CoV-2 gestational exposure was not associated with SDD. Exposure in the first gestational trimester increased SDD risk by 2.15 times compared to the third. Cesarean delivery predicted SDD (OR 1.56; 95%CI 1.01-2.42) and HRDD (OR 1.91; 95%CI 1.04-3.48). Additionally, suspected maternal depression predicted SDD (OR 1.76; 95%CI 1.01-3.10).

CONCLUSION

SARS-CoV-2 gestational exposure did not increase the developmental delay risk. However, our findings suggest that the earlier the gestational exposure, the greater the developmental delay risk at 12 months. Cesarean delivery and suspected maternal depression increased the developmental delay risk, independent of virus exposure.

Neonatal and Infant Lung Disorders: Glossary, Practical Approach, and Diagnoses

A multitude of lung disorders ranging from congenital and genetic anomalies to iatrogenic complications can affect the neonate or the infant within the first year of life. Neonatal and infant chest imaging, predominantly by plain radiography and computed tomography, is frequently employed to aid in diagnosis and management; however, these disorders can be challenging to differentiate due to their broad-ranging, and frequently overlapping radiographic features. A systematic and practical approach to imaging interpretation which includes recognition of radiologic patterns, utilization of commonly accepted nomenclature and classification, as well as interpretation of imaging findings in conjunction with clinical history can not only assist radiologists to suggest the diagnosis, but also aid clinicians in management planning. The contents of this article were endorsed by the leadership of both the World Federation of Pediatric Imaging (WFPI), and the International Society of Pediatric Thoracic Imaging (ISPTI).

Type of delivery and perinatal outcomes in pregnant women diagnosed with COVID-19: A systematic review and meta-analysis

BACKGROUND

There is paucity in the literature that provides a comprehensive and evidence-based conclusion regarding this topic.

OBJECTIVE

To compare perinatal outcomes of vaginal and caesarean section delivery in women diagnosed with COVID-19 by meta-analysis of literature.

SEARCH STRATEGY

The search was conducted on MEDLINE, EMBASE, LILACS, CINAHL, Scopus, Web of Science and Cochrane Database of Systematic Reviews by 25th May 2022.

SELECTION CRITERIA

The inclusion criteria involved pregnant women diagnosed with COVID-19 who underwent caesarean section and those who had vaginal deliveries.

DATA COLLECTION AND ANALYSIS

The included studies were meta-analyzed for various outcomes including: Gestational age, maternal intensive care unit admission, maternal death, prematurity, newborn birth weight, newborn intensive care unit admission, Apgar scores, newborn death, and newborn vertical transmission of COVID-19. The meta-analysis was conducted using Comprehensive Meta-Analysis (CMA) software, version 3.3.070.

MAIN RESULTS

The meta-analyses included 2,566 deliveries (866 caesarean sections and 1,700 vaginal deliveries) and identified that caesarean section was significantly associated with increased prematurity (OR 2.5 [1.7; 3.6], p < 0.001), lower birth weight (-118 g [-170; -66], p < 0.001), and a higher need for maternal (OR 9.54 [5.22; 17.43], p < 0.01) and neonatal intensive care unit intervention (OR 3.67 [2.71; 4.96], p < 0.01) compared to vaginal delivery.

CONCLUSION

COVID-19 infection alone should not be an indication for caesarean section as there is insufficient evidence that caesarean section reduces mortality, improves birth conditions, or prevents vertical transmission. Additionally, caesarean section is associated with poorer perinatal outcomes compared to vaginal delivery.

COVID-19: A Challenge to the Safety of Assisted Reproduction

There is an increased risk of becoming pregnant through fertility treatments using assisted reproductive technology (ART) during the COVID-19 pandemic. The aim of this review is to gather comprehensive data from the existing literature on the potential risks of fertility management during the pandemic period, and outline strategies to mitigate them, with a focus on the hormonal and surgical procedures of ART. A comprehensive search of the scientific literature on COVID-19 in relation to fertility was conducted in the PubMed database using the keywords "coronavirus," "COVID-19," "SARS-CoV-2" and "pregnancy," "fertility," "urogenital system," "vertical transmission," "assisted human reproduction," "controlled ovarian stimulation," "oocyte retrieval," "in vitro fertilization," "hormones," "surgical procedures," "embryos," "oocytes," "sperm," "semen," "ovary," "testis," "ACE-2 receptor," "immunology," "cytokine storm," and "coagulation," from January 2020-July 2022. Published data on pregnancy and COVID-19, and the interaction of the urogenital system and SARS-CoV-2 is reported. The immunologic and prothrombotic profiles of patients with COVID-19, and their increased risks from controlled ovarian stimulation (COS) and ART surgeries, and how these procedures could facilitate COVID-19 and/or contribute to the severity of the disease by enhancing the cytokine storm are summarized. Strategies to prevent complications during COS that could increase the risks of the disease in pre-symptomatic patients are considered. The impact of SARS-CoV-2 on pre-symptomatic infertile patients presents a challenge to find ways to avoid the increased hormonal, immunologic, and prothrombotic risks presented by the use of COS in ART protocols during the COVID-19 outbreak. Safe ART procedures and recommendations are highlighted.

COVID-19 during pregnancy could potentially affect placental function

OBJECTIVE

COVID-19 is an ongoing pandemic and has been extensively studied. However, the effects of COVID-19 during pregnancy, particularly on placental function, have not been verified. In this study, we used blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) to evaluate whether COVID-19 incidence during pregnancy has any lasting effects with respect to placental oxygenation.

METHODS

This is a case-control study, in which eight cases of singleton pregnancies before 30 weeks gestation with COVID-19 mothers were included. Placental oxygenation was evaluated using BOLD-MRI after 32 weeks of gestation. BOLD-MRI was consecutively performed under normoxia (21% O2), hyperoxia (100% O2), and normoxia for 4 min each. Individual placental time-activity curves were evaluated to calculate the peak score (peakΔR2*) and the time from the start of maternal oxygen administration to the time of peakΔR2* (time to peakΔR2*). Eighteen COVID-19-free normal pregnancies from a previous study were used as the control group.

RESULTS

No significant differences were found between the two groups regarding maternal background, number of days of delivery, birth weight, and placental weight. The parameter peakΔR2* was significantly decreased in the COVID-19 group (8 ± 3 vs. 5 ± 1, p < .001); however, there was no significant difference in time to peakΔR2* (458 ± 74 s vs. 471 ± 33 s, p = .644).

CONCLUSIONS

In this study, BOLD-MRI was used to evaluate placental oxygenation during pregnancy in COVID-19-affected patients. COVID-19 during pregnancy decreased placental oxygenation even post-illness, but had no effect on fetal growth; further investigation of the possible effects of COVID-19 on the fetus and mother is warranted.

Umbilical cord clamping in the early phases of the COVID-19 era - a systematic review and meta-analysis of reported practice and recommendations in guidelines

OBJECTIVES

At the beginning of the COVID-19 pandemic, delayed umbilical cord clamping (CC) at birth may have been commonly discouraged despite a lack of convincing evidence of mother-to-neonate SARS-CoV-2 transmission. We aimed to systematically review guidelines, and reports of practice and to analyze associations between timing of CC and mother-to-neonate SARS-CoV-2 transmission during the early phases of the pandemic.

METHODS

Major databases were searched from December 1, 2019, to July 20, 2021.

INCLUSION

studies and guidelines describing CC practice in women with SARS-CoV-2 infection during pregnancy until 2 postnatal days, giving birth to live-born neonates.

EXCLUSION

no extractable data. Two reviewers independently screened studies for eligibility and assessed study quality. Pooled prevalence rates were calculated.

RESULTS

Forty-eight studies (1476 neonates) and 40 guidelines were included. Delayed CC was recommended in 70.0% of the guidelines. Nevertheless, delayed CC was reported less often than early CC: 262/1476 (17.8%) vs 511/1476 (34.6%). Neonatal SARS-CoV-2 positivity rates were similar following delayed (1.2%) and early CC (1.3%). Most SARS-CoV-2 transmissions (93.3%) occurred in utero.

CONCLUSION

Delayed CC did not seem to increase mother-to-neonate SARS-CoV-2 transmission. Due to its benefits, it should be encouraged even in births where the mother has a SARS-CoV-2 infection.

SYSTEMATIC REVIEW REGISTRATION

Prospero CRD42020199500.

The protective role of maternal genetic immunization on maternal-fetal health and welfare

Pregnancy is a critical period associated with alterations in physiologic, biologic, and immunologic processes, which can affect maternal-fetal health through development of several infectious diseases. At birth, neonates have an immature immune system that makes them more susceptible to severe viral infections and diseases. For this reason, different maternal nutritional and immunization interventions have been used to improve the immune and health status of the mother and her neonate through passive immunity. Here, we reviewed the protective role of maternal immunization with different types of vaccines, especially genetic vaccines, during pregnancy in maternal-fetal health, immune response, colostrum quality, immune response, and anti-oxidative status. For this purpose, we have used different scientific databases (PubMed and Google Scholar) and other official web pages. We customized the search period range from the year 2000 to 2023 using the key words "maternal immunization" OR "gestation period/pregnancy" OR "genetic vaccination" OR "maternal-fetal health" OR "micronutrients" OR "neonatal immunity" "oxidative stress" OR "colostrum quality". The evidence demonstrated that inactivated or killed vaccines produced significant immune protection in the mother and fetus. Furthermore, most recent studies have suggested that the use of genetic vaccines (mRNA and DNA) during pregnancy is efficient at triggering the immune response in mother and neonate without the risk of undesired pregnancy outcomes. However, factors such as maternal redox balance, nutritional status, and the timing of immunization play essential roles in regulating immune response inflammatory status, antioxidant capacity, and the welfare of both the pregnant mother and her newborn.

Comparative clinical and placental pathologic characteristics in pregnancies with and without SARS-CoV-2 infection

OBJECTIVES

To compare the clinical and morphological characteristics of the "mother-placenta-fetus" system in high risk pregnant women of three groups: no SARS-CoV-2 infection, mild SARS-CoV-2 infection, and severe SARS-CoV-2 infection.

METHODS

A case-control study was performed for all deliveries, at 28 weeks' gestation or greater, who had standard indications for placental pathologic examination. Three groups were formed: (1) control group (no SARS-CoV-2 infection), (2) mild SARS-CoV-2 infection, (3) severe SARS-CoV-2 infection. High-risk pregnancies were registered in all cases in the study groups. The examination of the placenta and the selection of fragments of placental tissue were carried out in accordance with the consensus recommendations of the Amsterdam Placental Workshop Group. The sections were subjected to standard processing and stained with hematoxylin and eosin according to the standard protocol. All cases were reviewed by two pathologists, which did not know any information on pregnancy outcome and clinical data. Statistical analysis was performed using SPSS, p<0.05 was considered statistically significant.

RESULTS

Women with severe SARS-CoV-2 infection had an increased rate of multimorbidity including diabetes, chronic hypertension and obesity (p<0.01) compared with the other groups. Placentas at severe COVID-19 course were damaged by both chronic and acute injuries, in comparison to the mild and control groups (p<0.001). Also an important finding in severe COVID-19 was diffuse necrosis of the villous trophoblast - homogenization, diffuse circular eosinophilic masses surrounding the chorionic villi.

CONCLUSIONS

Women with multimorbidity are an "at-risk" subgroup for severe SARS-CoV-2 infection and greater likelihood of both placental damage and perinatal hypoxic-ischemic events. These results suggest that patient education, SARS-CoV-2 disease monitoring and preventive measures would be of benefit to this group.

SARS-CoV-2 Infection in Late Pregnancy and Childbirth from the Perspective of Perinatal Pathology

This review focuses on SARS-CoV-2 infection in placental and fetal tissues. Viremia is rare in infected pregnant women, and the virus is seldom amplified from placental tissues. Definite and probable placental infection requires the demonstration of viral RNA or proteins using in situ hybridization (ISH) and immunohistochemistry (IHC). Small subsets (1.0-7.9%, median 2.8%) of placentas of SARS-CoV-2-positive women showed definite infection accompanied by a characteristic histopathology named SARS-CoV-2 placentitis (SP). The conventionally accepted histopathological criteria for SP include the triad of intervillositis, perivillous fibrin deposition, and trophoblast necrosis. SP was shown to be independent of the clinical severity of the infection, but associated with stillbirth in cases where destructive lesions affecting more than 75% of the placental tissue resulted in placental insufficiency and severe fetal hypoxic-ischemic injury. An association between maternal thrombophilia and SP was shown in a subset of cases, suggesting a synergy of the infection and deficient coagulation cascade as one of the mechanisms of the pathologic accumulation of fibrin in affected placentas. The virus was amplified from fetal tissues in approximately 40% of SP cases, but definite fetal involvement demonstrated using ISH or IHC is exceptionally rare. The placental pathology in SARS-CoV-2-positive women also includes chronic lesions associated with placental malperfusion in the absence of definite or probable placental infection. The direct viral causation of the vascular malperfusion of the placenta in COVID-19 is debatable, and common predispositions (hypertension, diabetes, and obesity) may play a role.