Léo Pomar

Haute Ecole de Santé Vaud / Lausanne University Hospital

Purpose Over the past decade, the Amazon basin has faced numerous infectious epidemics. Our comprehension of the actual extent of these infections during pregnancy remains limited. This study aimed to clarify the clinical and epidemiological features of emerging and re-emerging infectious diseases during pregnancy in western French Guiana and along...

Objective To assess the accuracy of corpus callosum (CC) biometry, including sub-segments, using 3D super-resolution fetal brain MRI (SR) compared to 2D or 3D ultrasound (US) and clinical low-resolution T2-weighted MRI (T2WS). Method Fetal brain biometry was conducted by two observers on 57 subjects [21–35 weeks of gestational age (GA)], including...

Background Lack of Cytomegalovirus (CMV) knowledge among healthcare professionals has been proven to be the main threat to pregnant women's awareness, preventing them from reducing the risk of infection. The aims of this study were to assess the knowledge and practices of French-speaking Swiss perinatal professionals in terms of CMV prevention, as...

Mosquito-borne arboviral diseases are a global concern and can have severe consequences on maternal, neonatal, and child health. Their impact on pregnancy tends to be neglected in developing countries. Despite hundreds of millions of infections, 90% pregnancies being exposed, scientific data on pregnant women is poor and sometimes non-existent. Rec...

Objective: To assess fetal and neonatal eyes abnormalities and their progression during the last ZIKV outbreak and summarize learned lessons. Methods: A systematic review and meta-analysis was conducted by a team of obstetricians and ophthalmologists. Results: Studies reporting ocular abnormalities during the prenatal (n = 5) and postnatal (n...

Objective The aim of this study was to describe different causes and consequences of fever during pregnancy in Western French Guiana and along the Maroni River. Study design A retrospective single-center study including all patients with a history of documented fever ≥ 38°C during pregnancy at the West French Guiana Hospital for 9 years. Postpartu...

Objective: To assess the accuracy of corpus callosum (CC) and its sub-segments' biometry by super-resolution (SR) 3-dimensional fetal brain MRI in comparison to measurements in 2-dimensional or 3-dimensional ultrasonography (US) and clinical low-resolution T2-weighted MRI sequences (T2WS). Method: We performed fetal brain biometry of the overall le...

Objectives: This study aimed to evaluate the risk of congenital malformation among pregnant women exposed to the mRNA COVID-19 vaccines during the first trimester of pregnancy, which is a developmental period where the fetus is at risk of teratogenicity. Methods: Pregnant women were prospectively enrolled from March 2021 to March 2022, at the ti...

Linked article: There is a comment on this article by Paladini et al. Click here to view the Editorial.

Background: Pregnancy mobile applications (apps) have grown in popularity over the past decade, with some being used to promote study recruitment or health behaviors. However, no app serves as an all-in-one solution for collecting general data for research purposes and providing women with useful and desirable features. Aim: To create and develop a...

With COVID-19 vaccination hesitancy at around 50% in the obstetric population, it is critical to identify which women should be addressed and how. Our study aimed to assess COVID-19 vaccination willingness among pregnant and postpartum women in Europe and to investigate associated determinants. This study was a cross-sectional, web-based survey con...

Introduction: Gomez-Lopez-Hernandez Syndrome (GLHS), also known as cerebello-trigeminal-dermal dysplasia is an extremely rare neuro-cutaneous disease, classically described by the triad of rhombencephalosynapsis (RES), bilateral focal alopecia and trigeminal anesthesia. The clinical and radiographic spectrum of GLHS is now known to be broader, inc...

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Cytomegalovirus infection is the most common congenital infection, affecting about 1% of births worldwide. Several primary, secondary, and tertiary prevention strategies are already available during the prenatal period to help mitigate the immediate and long-term consequences of this infection. In this review, we aim to present and assess the effic...

Background Despite being first identified in 1947, Zika virus-related outbreaks were first described starting from 2007 culminating with the 2015 Latin American outbreak. Hypotheses indicate that the virus has been circulating in Asia for decades, but reports are scarce. Methods We performed serological analysis and screened placental samples isol...

Objective: We aimed to describe the epidemiology of intrauterine fetal deaths in multiethnic western French Guiana and to assess its main causes and risk factors. Study design: A retrospective descriptive study was conducted based on data from January 2016 to December 2021. All information on stillbirth with a gestational age ≥20 weeks in the We...

Background SARS-CoV-2 positive pregnant women are at higher risk of adverse outcomes, but little evidence is available on how variants impact that risk. We aim to evaluate maternal and perinatal outcomes among unvaccinated pregnant women that tested positive for SARS-CoV-2, stratified by pre-Delta, Delta, and Omicron periods. Methods This prospect...

Aim The objective of this study was to describe the use of COVID‐19‐related medicines during pregnancy and their evolution between the early/late periods of the pandemic. Methods Pregnant women who tested positive for SARS‐CoV‐2 from March 2020 to July 2021 were included using the COVI‐PREG registry. Exposure to the following COVID‐19‐related medi...

Lymphocytic choriomeningitis virus (LCMV) is an emerging neuroteratogen which can infect humans via contact with urine, feces, saliva, or blood of infected rodents. When the infection occurs during pregnancy, there is a risk of transplacental infection with subsequent neurological or visual impairment in the fetus. In this article, we describe a ca...

Monkeypox virus (MPXV) has emerged as a threatening zoonosis. Its spread around the world has been growing fast over the last 2 years, particularly in 2022. The reasons for this sudden spread are probably multifactorial. The R0 values of the two MPXV clades are rather low, and a massive pandemic is considered unlikely, although the increase in the...

The aim of our study was to evaluate the mental health of pregnant individuals during the early COVID-19 pandemic and the potential factors associated. A Swiss online survey was proposed to individuals who gave birth during the pandemic period from March 2020. The Edinburgh Postnatal Depression Scale (EPDS), Generalized Anxiety Disorder 7 questions...

Study question: Did the first wave of the COVID-19 pandemic have an impact on monthly birth rates in Europe? Summary answer: Using datasets on live births per month in Europe, collected from the Human Fertility Database, we found a -14.1% decline in live births in January 2021 (i.e. 9-10 months after the epidemic peaks and first lockdowns), comp...

Background Pregnant individuals with coronavirus disease 2019 (COVID-19) are at increased risk of severe disease, prematurity, and stillbirth. In March 2021, vaccination for at risk pregnant women was recommended in Switzerland, expanding this to all pregnant women in May 2021. Our aim was to assess the safety of mRNA COVID-19 vaccines in pregnancy...

Information on medication utilization among pregnant and postpartum women during the pandemic is lacking. We described the prevalence and patterns of self-reported medication use among pregnant and postpartum women during the third wave of the pandemic (June–August 2021). An online questionnaire was distributed in five European countries between Ju...

Information on medication utilization among pregnant and postpartum women during the pandemic is lacking. We described the prevalence and patterns of self-reported medication use among pregnant and postpartum women during the third wave of the pandemic (June - August 2021). An online questionnaire was distributed in five European countries between...

We report a case of vertical transmission of Tonate virus in a pregnant woman from French Guiana. The fetus showed severe necrotic and hemorrhagic lesions of the brain and spinal cord. Clinicians should be made aware of possible adverse fetal outcomes in pregnant women infected with Tonate virus.

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Insight into the epidemiology of perinatal medication use during the COVID-19 pandemic is scarce. Therefore, a cross-sectional study using an anonymous web survey was performed in Ireland, Norway, Switzerland, the Netherlands, and United Kingdom (UK) to investigate the prevalence and type of medications used by pregnant and breastfeeding women duri...

Objectives: To characterize a suggestive prenatal imaging pattern of Aicardi syndrome using ultrasound and MRI. Methods: Based on a retrospective international series of Aicardi syndrome cases from tertiary centers encountered over a 20-year period (2000 - 2020), we investigated the frequencies of the imaging features in order to characterize an...

Neonatal COVID-19 is rare and mainly results from postnatal transmission. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), however, can infect the placenta and compromise its function. We present two cases of decreased fetal movements and abnormal fetal heart rhythm 5 days after mild maternal COVID-19, requiring emergency caesarean sec...

Information on the impact of the COVID-19 pandemic on pregnancy and breastfeeding experiences, as well as on perinatal mental health in Switzerland is limited. In Switzerland, there are few national studies and little information. Using an anonymous online survey accessible after the first wave of the outbreak in Switzerland, we have investigated h...

We would like to thank Stroobandt, S. and Stroobandt, R. for showing interest in our paper [...]

Pregnant women may be at higher risk of severe complications associated with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which may lead to obstetrical complications. We performed a case control study comparing pregnant women with severe coronavirus disease 19 (cases) to pregnant women with a milder form (controls) enrolled in...

As pregnant women are at high risk of severe SARS-CoV-2 infection and COVID-19 vaccines are available in Switzerland, this study aimed to assess the willingness of Swiss pregnant and breastfeeding women to become vaccinated. Through a cross-sectional online study conducted after the first pandemic wave, vaccination practices and willingness to beco...

Little is known about the long-term neurological development of children diagnosed with congenital Zika infection at birth. Here, we report the imaging and clinical outcomes up to three years of life of a cohort of 129 children exposed to Zika virus in utero. Eighteen of them (14%) had a laboratory confirmed congenital Zika infection at birth. Infe...

Linked article: This Correspondence comments on Stern et al. Click here to view the article.

Objectives: To describe the prenatal neuroimaging spectrum of rhombencephalosynapsis (RES) and the criteria for the classification according to the severity of the vermian anomaly. Methods In this multicenter retrospective study of fetuses with a diagnosis of RES, the medical records, ultrasound and brain MR images were comprehensively evaluated f...

The COVID-19 pandemic may be of particular concern for pregnant and breastfeeding women. We aimed to explore their beliefs about the coronavirus and COVID-19 vaccine willingness and to assess the impact of the pandemic on perinatal experiences and practices. A multinational, cross-sectional, web-based study was performed in six European countries b...

In this multicentre cohort study, we evaluated the risks of maternal ZIKV infections and adverse pregnancy outcomes among exposed travellers compared to women living in areas with ZIKV circulation (residents). The risk of maternal infection was lower among travellers compared to residents: 25.0% (n = 36/144) versus 42.9% (n = 309/721); aRR 0.6; 95%...

Introduction: Evidence on perinatal mental health during the COVID-19 pandemic and its potential determinants is limited. Therefore, this multinational study aimed to assess the mental health status of pregnant and breastfeeding women during the pandemic, and to explore potential associations between depressive symptoms, anxiety and stress, and wo...

The objective is to study the reproducibility and reliability of the fetal corpus callosum measurements between two-dimensional (2D) and three-dimensional (3D) acquisitions. This prospective study enrolled 475 fetuses, monitored between 18 and 38 weeks of gestation by two operators. Starting from a transcerebellar axial plane, 3D and 2D mid-sagitta...

Whether prolonged maternal viremia after Zika virus infection represents a risk factor for maternal–fetal transmission and subsequent adverse outcomes remains unclear. In this prospective cohort study in French Guiana, we enrolled Zika virus–infected pregnant women with a positive PCR result at inclusion and noninfected pregnant women; both groups...

Objective To describe the proportions of asymptomatic, mild and severe diseases in infected pregnant women admitted for delivery. To compare maternal, fetal and neonatal outcomes of SARS-CoV-2 infected pregnant women with those of non-infected patients. Study design Through an universal PCR testing for SARS-COV-2 at admission (not symptoms-based),...

Background. Recent evidence suggests that pregnant women may be at higher risk of severe disease associated with the emerging pandemic severe acute respiratory syndrome coronavirus SARS-CoV-2), while their fetuses/newborns could suffer from preterm birth, growth restriction and neonatal infections. The magnitude of this increased risk and specific...

Background. Recent evidence suggests that pregnant women may be at higher risk of severe disease associated with the emerging pandemic severe acute respiratory syndrome coronavirus (SARS-CoV-2), while their fetuses/newborns could suffer from preterm birth, growth restriction and neonatal infections. The magnitude of this increased risk and specific...

Zika virus (ZIKV), a neurotropic single-stranded RNA flavivirus, remains an important cause of congenital infection, fetal microcephaly, and Guillain-Barré syndrome in populations where ZIKV has adapted to a nexus involving the Aedes mosquitoes and humans. To date, outbreaks of ZIKV have occurred in Africa, Southeast Asia, the Pacific islands, the...

This commentary describes the creation of the Zika Virus Individual Participant Data Consortium, a global collaboration to address outstanding questions in Zika virus (ZIKV) epidemiology through conducting an individual participant data meta-analysis (IPD-MA). The aims of the IPD-MA are to (1) estimate the absolute and relative risks of miscarriage...

The ability of ultrasound to predict postpartum hemorrhage remains poorly described. The aim of this study was to evaluate whether ultrasound measurement of intrauterine content can predict blood loss and postpartum hemorrhage after vaginal delivery. We used a preliminary prospective monocentric study of 201 women who delivered vaginally after 34 w...

Objective: To describe the lesions detected by prenatal ultrasound examination in congenital toxoplasmosis (CT). Methods: We retrospectively analyzed all cases of fetal infection with T. gondii with ultrasound anomalies described by fetal medicine experts in 2009-2019 in 30 French centers. Results: Eighty-eight cases of CT were included. Forty...

Background: Although it is known that Zika virus (ZIKV) infection during pregnancy may lead to microcephaly in the fetus, the prognostic factors associated with this tragic disorder remain unclear. We conducted a systematic review and meta-analysis to assess the prognostic factors associated with the incidence of microcephaly in congenital ZIKV in...

The current COVID-19 pandemic has resulted in an unprecedented worldwide health crisis. The increased vulnerability of pregnant women as well as past experience from previous coronavirus epidemics are cause for concern of maternal and fetal complications. The rapid outbreak of the disease combined with the uncertainty, as a direct result of the lac...

Since December 2019, the novel SARS‐CoV‐2 outbreak has resulted in millions of cases and more than 200,000 deaths worldwide. The clinical course among non‐pregnant women has been described but data about potential risks for women and their fetus remain scarce. The SARS and MERS epidemics were responsible for miscarriages, adverse fetal and neonatal...

Emerging infectious diseases require a global approach and adaptive tools to allow for rapid and comprehensive characterisation of the risks associated with the disease, particularly in pregnancy. Pregnant women are particularly vulnerable to infections because of their relative immunosuppressed state, restricted cardiorespiratory capacity, and the...

To contain the COVID-19 global outbreak, many governments have proposed to close schools. This measure was used in previous epidemics such as the H1N1 2009 pandemic, but its efficacy remains debatable. A systematic review of 79 epidemiological studies concluded that it remains unclear how significantly school closures contribute to the reduction of...

ADAPTED TO NEW DATA Guidelines for pregnant women with suspected SARS-CoV-2 infection.

Objectives: To correlate placental thickness during pregnancy and histopathological results with placental Zika virus (ZIKV) infection. Methods: During the ZIKV epidemic in French Guiana, trans-placental contamination was defined either by a positive RT-PCR or identification of specific IgM in at least one placental, fetal or neonatal sample. Pl...