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Pomar Léo

Professeur HES associé

Main contract

Professeur HES associé

Desktop: CR19/20/20.01

HESAV - Haute Ecole de Santé Vaud
Avenue de Beaumont 21, 1011 Lausanne, CH

Faculty
Santé

Main Degree Programme
Sage-femme

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2025

How COVID-19 treatment in pregnancy reflects healthcare utilization during a pandemic :

Scientific paper ArODES

a two-stage individual participant data meta-analysis combining case-based registries

Emeline Maisonneuve, Odette De Bruin, Guillaume Favre, Erin Oakley, Jenny Yeon Hee Kim, Fouzia Farooq, Nouf Al-Fadel, Abdulaali Almutairi, Maria del Mar Gil, Irene Fernandez Buhigas, Silvia Visentin, Erich Cosmi, Fernanda Surita, Renato T. Souza, José G. Cecatti, Maria Laura Costa, Jose Sanin-Blair, Jorge E. Tolosa, Eran Hadar, Anna Goncé, Christophe Poncelet, Fabienne Forestier, Thibaud Quibel, Béatrice Eggel-Hort, Romina Capoccia Brugger, Daniel Surbek, Luigi Raio, Anda-Petronela Radan, Monya Todesco-Bernasconi, Cécile Monod, Leonard Schäffer, Anett Harnadi, Sayed Hamid Mousavi, Diogo Ayres-de-Campos, Léo Pomar, Joanna Sichitiu, Laurent J. Salomon, Yves Ville, Andrea Papadia, Marie-Claude Rossier, Lavinia Schuler-Faccini, Natalya Goncalves Pereira, Adolfo Etchegaray, Albaro Jose Nieto-Calvache, Michael Geary, Javiera Fuenzalida, Claudia Grawe, Albert I. Ko, Silke Johann, Marco De Santis, Cora Alexandra Voekt, Najeh Hcini, Karin Nielsen-Saines, Charles Garabedian, Loïc Sentilhes, Otto H. May Feuerschuette, Grit Vetter, Manggala Pasca Wardhana, Irida Dajti, Kitty W. M. Bloemenkamp, Satu J. Siiskonen, Emily R. Smith, David Baud, Alice Panchaud, Miriam C. J. M. Sturkenboom

Pharmacoepidemiology and Drug Safety, 2025, 34, 7, Article no e70180

Link to the publication

Summary:

Purpose: To describe an international response to the COVID-19 pandemic by estimating the prevalence of medication use for COVID-19 treatment in pregnancy, stratified by hospitalization, trimester of pregnancy, and country. Methods: We conducted a two-stage individual participant data meta-analysis of proportions from primary data on medications used to treat COVID-19 during pregnancy. A common data model was developed to pool the data from single-country and international registries. Data from pregnant individuals with COVID-19 between February 2020 and October 2022 were included in study platforms across 9 data sources. Patient information was abstracted from medical records. Results: Among 24 937 pregnant individuals, the pooled prevalences of individuals receiving medications to treat COVID-19 were: 34.7% heparin, 9.8% antibiotics, 4.9% corticosteroids, 2.2% antivirals, 0.8% antimalarials, 0.3% convalescent plasma, 0.2% immunosuppressants, and 0.02% monoclonal antibodies. Prevalence of medication use was higher in hospitalized individuals than in non-hospitalized individuals: 58.4% versus 17.9% for heparin, 26.9% versus 5.7% for antibiotics, 17.5% versus 1.3% for corticosteroids, 10.3% versus 0.3% for antivirals, and 4.5% versus 0.1% for antimalarials. The prevalence of corticosteroid use was lower in the first trimester (0.1%) compared with the second (7.2%) and third (4.9%) trimesters of pregnancy. The prevalence of medications differed widely across countries. Conclusion: Medication to treat COVID-19 was more frequently used in pregnant individuals hospitalized for COVID-19. Corticosteroids were used less in the first trimester of pregnancy. The differences in use between countries could reflect differences in the clinical management and access to medications for this population at risk of severe disease.

Enhancing perinatal health patient information through ChatGPT :

Scientific paper ArODES

an accuracy study

Pauline L. M. de Vries, David Baud, Stéphanie Baggio, Michael Ceulemans, Guillaume Favre, Eva Gerbier, Hélène Legardeur, Emeline Maisonneuve, Carlos Andrés Peña-Reyes, Léo Pomar, Ursula Winterfeld, Alice Panchaud

PEC Innovation, 2025, 6, 100381

Link to the publication

Summary:

Objectives : To evaluate ChatGPT's accuracy as information source for women and maternity-care workers on “nutrition” and “red flags” in pregnancy. Methods : Accuracy of ChatGPT-generated recommendations was assessed by a 5-point Likert scale by eight raters for ten indicators per topic in four languages (French, English, German and Dutch). Accuracy and interrater agreement were calculated per topic and language. Results : For both topics, median accuracy scores of ChatGPT-generated recommendations were excellent (5.0; IQR 4–5) independently of language. Median accuracy scores varied with a maximum of 1 on a 5-point Likert-scare according to question's framing. Overall accuracy scores were 83–89 % for ‘nutrition in pregnancy’ versus 96–98 % for ‘red flags in pregnancy’. Inter-rater agreement was good to excellent for both topics. Conclusion : Although ChatGPT generated accurate recommendations regarding the tested indicators for nutrition and red flags during pregnancy, women should be aware of ChatGPT's limitations such as inconsistencies according to formulation, language and the woman's personal context. Innovation : Despite a growing interest in the potential use of artificial intelligence in healthcare, this is, to the best of our knowledge, the first study assessing potential limitations that may impact accuracy of ChatGPT-generated recommendations such as language and question-framing in key domains of perinatal health.

Prenatal diagnosis of Blake's pouch cyst :

Scientific paper ArODES

from natural history to management

Léo Pomar, J. Sichitiu, S. Lebon, D. Paladini

Ultrasound in Obstetrics & Gynecology, 2025, 66, 1, 5-10

Link to the publication

Transvaginal ultrasound assessment of corpus callosal length in the fetus :

Scientific paper ArODES

multicenter cross-sectional study

D. Paladini, S. Parodi, H. Xie, F. Viñals, K. Haratz, Léo Pomar

Ultrasound in Obstetrics & Gynecology, 2025, 65, 6, 703-711

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Summary:

Objective: To produce reference ranges and Z-scores for corpus callosal (CC) length in the fetus, based on transvaginal three-dimensional (3D) ultrasound imaging. Methods: This was a cross-sectional multicenter retrospective study based on 3D volume dataset acquisitions of the fetal CC between the 15th and 37th weeks of gestation. Only volume datasets acquired transvaginally through the anterior fontanelle were selected. After plane alignment on multiplanar imaging, the length of the CC was measured edge-to-edge on magnified images. Intra- and interobserver variability were assessed and the related intraclass correlation coefficients (ICC) calculated. Biometric charts to assess the reference values for fetal CC were obtained using the method proposed by Altman in 1993. Results: The 13 participating centers provided valid data for 2131 patients. Excellent agreement was observed for both intra- and interobserver analysis, with an ICC range of 0.98–1.00. A quadratic model was used for construction of the reference charts, modified with the insertion of cubic spline coefficients with a single knot at 18 gestational weeks, to recover an apparent lack of fit at lower gestational ages. Centile reference values and the corresponding Z-scores were produced for CC length between 15 and 37 gestational weeks. Conclusions: This multicenter study presents growth charts for the fetal CC, addressing the critical methodological weaknesses of several previous studies. An even distribution of cases across all gestational weeks, robust statistical methodology and a standardized, high-resolution transvaginal neurosonographic technique represent key factors supporting the reliability of the biometric curves presented here. © 2025 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Adverse fetal and perinatal outcomes associated with Zika virus infection during pregnancy :

Scientific paper ArODES

an individual participant data meta-analysis

The Zika Virus Individual Participant Data Consortium, Léo Pomar

eClinicalMedicine, 2025, vol. 83, Article no 103231

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Summary:

Background: Zika virus (ZIKV) infection during pregnancy is associated with an increased risk of congenital malformations. The prevalence of short and long-term consequences, however, remains uncertain due to heterogeneity across studies. Individual Participant Data Meta-Analysis (IPD-MA) offers an alternative approach to provide more precise and generalisable estimates through data harmonisation across studies, allowing for standardised definitions and exploration of heterogeneity. This project was undertaken to estimate absolute and relative risks of adverse outcomes for individuals with ZIKV infection during pregnancy. Methods: IPD-MA studies and their datasets were identified through a systematic search conducted in 2018 with the following criteria: observational longitudinal or surveillance-based studies investigating ZIKV during pregnancy or at birth, measured fetal, infant, or child outcomes, and included at least 10 participants. Here we used IPD data shared by March 2022 from 18 studies from international health organisations and research networks, comprising 24 unique datasets, in 11 countries. Datasets were harmonised with standardised definitions, using variables related to pregnant individuals, methods used for ZIKV diagnoses, fetal characteristics and outcomes, and pooled for analysis. Frequentist and Bayesian regression methods were applied to estimate outcome prevalence and evaluate the association between maternal ZIKV infection and fetal loss, microcephaly and congenital zika syndrome as primary outcomes. Findings: Data including 9568 pregnant individuals and 9608 newborns, were harmonised. The risk of severe primary microcephaly was significantly higher in ZIKV-positive pregnancies (1.5%, CI 0.8%–2.7%) compared to ZIKV-negative ones (0.3%, CI 0.1%–1.0%), with a relative risk of 4.5 (CI 1.5–13.3) in the one-stage meta-analysis. While some risk estimates were consistent between Bayesian and Frequentist methods, estimates for other outcomes varied, underscoring the influence of both the analytical approach and the definition of ZIKV on the associations. Interpretation: Our findings align with previously published meta-analyses and indicate an added burden to adverse pregnancy outcomes with higher prevalence compared to pre-epidemic population-based average values. Future research should focus on additional outcomes with clear definitions of maternal infection. Women of reproductive age should be informed about the risks of Zika infection during pregnancy to support reproductive planning. Funding: This project was supported by the Wellcome Trust grant number 206532/Z/17/Z, the WHO Health Emergencies Programme Global Arbovirus Initiative, and the WHO Department of Sexual and Reproductive Health and Research, including the Human Reproduction Special Programme (HRP).

Awareness and knowledge of cytomegalovirus infection among pregnant women in French-speaking Switzerland

Scientific paper ArODES

Dina Hussami, Pauline Sartori, Alexandre Farin, Wawrzyniec Rieder, Léo Pomar

BMC Pregnancy and Childbirth, 2025, 25, 1, Article no 424

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Summary:

Background: In Switzerland, cytomegalovirus (CMV) is the most common congenital infection, affecting more than 400 newborns per year. It is also the leading non-genetic cause of neurosensory impairment in children. The aims of this study were to assess the awareness, general knowledge and knowledge of hygiene measures related to CMV among pregnant women in French-speaking Switzerland, as well as identify baseline characteristics potentially associated with a better knowledge of CMV. Methods: A regional cross-sectionnal study carried out in French-speaking Switzerland between May and December 2022, using a 36-item questionnaire available through a QR code. Results: The majority of pregnant women surveyed, 61.6% (514/834), had already heard about CMV. Half the participants (50.4%, 375/743) knew how to protect themselves against this infection. Only 7.2% (60/834) were aware of all the consequences of congenital CMV infection in newborns, and only 1.2% (10/834) knew all the general facts about this virus (transmission, screening, treatment, fetal and maternal risks). An education above secondary level and having a high-risk profession (daycare of healthcare providers) appeared to be factors independently associated with greater awareness and knowledge of CMV, and of the hygiene measures to protect against it. Having been followed by a midwife (only or in addition to an obstetrician) was also associated with a greater knowledge of the virus, and age over 30 and being multiparous were also factors independently associated with a better knowledge of hygiene measures to adopt against CMV. Conclusion: Awareness of CMV among pregnant women appears to have improved since a previous study conducted in Geneva in 2015. While knowledge of preventive measures among participants was insufficient to ensure comprehensive protection against CMV infection, it represents a significant improvement compared to previous studies. Further efforts are needed to enhance this knowledge to maximize its potential impact on prevention behaviors.

Prenatal diagnosis of Okur-Chung syndrome :

Scientific paper ArODES

ultrasound findings and implications of CSNK2A1 and KCNQ5 variants

Chiara Kratochwila, Joanna Sichitiu, Sébastien Lebon, Camille Kumps, Léo Pomar

Maternal-Fetal Medicine, 2025,7, 2, 116-118

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‘Neurodevelopmental outcomes of infants after in utero exposure to SARS-CoV-2 or mRNA COVID-19 vaccine compared to unexposed infants’ – Author’s reply

Scientific paper ArODES

David Baud, Léo Pomar, Emeline Maisonneuve, Ursula Winterfeld, Alice Panchaud, Guillaume Favre

Clinical Microbiology and Infection, 2025, 31, 4, 666-667

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2024

Neurodevelopmental outcomes of infants after in utero exposure to SARS-CoV-2 or mRNA-COVID-19 vaccine compared with unexposed infants :

Scientific paper ArODES

a COVI-PREG prospective cohort study

Guillaume Favre, Rebecca, L. Bromley, Matthew Bluett-Duncan, Emeline Maisonneuve, Léo Pomar, Charlotte Daire, Anda-Petronela Radan, Luigi Raio, Daniel Surbek, Carolin Blume, Stylianos Kalimeris, Yoann Madec, Juliane Schneider, Myriam Bickle Graz, Ursula Winterfeld, Alice Panchaud, David Baud

Clinical Microbiology and Infection, 2025, 31, 2, 266-273

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Summary:

Objectives : Data are lacking regarding the long-term consequences of SARS-CoV-2 and COVID-19 mRNA vaccine on infants exposed in utero. We aimed to evaluate the neurodevelopment of infants exposed prenatally to SARS-CoV-2 or mRNA-COVID-19 vaccine during pregnancy at 12 months after birth. Methods : Infants born to mothers exposed to SARS-CoV-2 or mRNA-COVID-19 vaccine during pregnancy, or unexposed to either the virus or the vaccine were enrolled from 2021 to 2023. Infants with prenatal exposure to the virus or vaccine were compared with infants without prenatal exposure to the virus and/or vaccine. Parents received a neurodevelopmental questionnaire (ages and stages questionnaire third edition) at 12 months after birth assessing five subdomains: communication, gross motor, fine motor, problem-solving, and personal social development. A low score was defined as <2 standard deviations below the normative mean in at least one of the subdomains. Results : A total of 330 infants were included (76 in the SARS-CoV-2 group, 153 in the mRNA-COVID-19 vaccine group, and 101 in the reference group). In utero exposure to the SARS-CoV-2 or mRNA-COVID-19 vaccine was not associated with an increased risk of a low score for at least one subdomain compared with the reference group. The crude ORs were 1.16 (95% CI, 0.59–2.28) and 1.04 (95% CI, 0.58–1.86), respectively. Results remained consistent in the multivariate analysis, showing no increased risk of a low score for at least one subdomain for infants exposed to the SARS-CoV-2 or mRNA-COVID-19 vaccine, compared with the reference group. The adjusted ORs were 1.74 (95% CI, 0.76–3.99) and 0.76 (95% CI, 0.39–1.49), respectively. Discussion : In utero exposure to SARS-CoV-2 or mRNA-COVID-19 vaccine was not associated with an increased risk of a low score for at least one ages and stages questionnaire third edition subdomain at 12 months after birth. Additional studies are needed to confirm our results, especially longer-term evaluation of infant development.

Connaissances des sages-femmes de Suisse romande sur le CMV

Professional paper ArODES

Marine Rempp, Elodie Savoy, Louise Tilbury, Pauline Sartori, Léo Pomar

Obstetrica, 2024, 8/9, 48-51

Link to the publication

Summary:

Le cytomégalovirus (CMV) est l’infection congénitale la plus fréquente en Suisse, touchant 0,5 à 1% des naissances. Grâce à une étude transversale menée en Suisse romande, les auteur·rice·s de cet article ont cherché à évaluer les pratiques de prévention et les connaissances des sage-femmes sur le CMV. Elles et il proposent ici diverses recommandations pour la pratique, en fonction des différents secteurs d’activité des sages-femmes.

Considering gestational age in the biological response of the fetus to cytomegalovirus :

Scientific paper ArODES

letter to the editors

Léo Pomar, Milos Stojanov, David Baud

American journal of obstetrics and gynecology, 2024, 231, 5, Art. e195

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Fetal blood sampling in cytomegalovirus infection :

Scientific paper ArODES

balancing the risks and benefits : letter to the editors

Léo Pomar, Joanna Sichitiu, David Baud

American journal of obstetrics and gynecology, 2024, 231, 2, e109

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Manuel Oxford en sciences sage-femme

Book ArODES

Janet Medforth, Linda Ball, Angela Walker, Sue Battersby, Sarah Stables, Claire De Labrusse, Alessia Abderhalden-Zellweger, Murielle Caldelari, Patricia Perrenoud, Mélanie Picavet, Pauline Thomas, Julie Flohic, Marielle Schmied, Diane Waller, Christelle Kaech, Léo Pomar, Magali Bonzon, Maëva Pretalli, Clémence Haydar, Franziska Schläppy Muntwyler, Maria-Pia Politis Mercier, Lucia Floris, Fabienne Salamin, Bénédicte Michoud, Yvonne Meyer, Harriet Thorn-Cole

2024, Chêne-Bourg : RMS éditions / Médecine & Hygiène, 1168 p.

Link to the publication

Summary:

Le Manuel Oxford en sciences sage-femme est une ressource unique, qui fournit aux sages-femmes tout ce dont ils et elles ont besoin dans leur pratique. Il réunit des informations concises, pratiques et spécialisées sur tous les aspects du rôle de sage-femme, allant des conseils pré-conceptuels à l’examen postnatal final de la mère et du bébé. Cette version traduite a été adaptée à la francophonie au niveau des actes, de la médication et des rôles des soignants, coordonnée par Claire de Labrusse et Alessia Abderhalden-Zellweger, et validée par la Filière Sage-femme de la Haute École de Santé Vaud, en Suisse.

Assessment of fetal corpus callosum biometry by 3D super-resolution reconstructed T2-weighted magnetic resonance imaging

Scientific paper ArODES

Samuel Lamon, Priscille de Dumast, Thomas Sanchez, Vincent Dunet, Léo Pomar, Yvan Vial, Mériam Koob, Meritxell Bach Cuadra

Frontiers in Neurology, 2024, 15, art. 1358741

Link to the publication

Summary:

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 11 cases of partial CC agenesis. Measures were performed by a junior observer (obs1) on US, T2WS and SR and by a senior neuroradiologist (obs2) on T2WS and SR. CC biometric regression with GA was established. Statistical analysis assessed agreement within and between modalities and observers. Results: This study shows robust SR to US concordance across gestation, surpassing T2WS. In obs1, SR aligns with US, except for genu and CC length (CCL), enhancing splenium visibility. In obs2, SR closely corresponds to US, differing in rostrum and CCL. The anterior CC (rostrum and genu) exhibits higher variability. SR’s regression aligns better with literature (US) for CCL, splenium and body than T2WS. SR is the method with the least missing values. Conclusion: SR yields CC biometry akin to US (excluding anterior CC). Thanks to superior 3D visualization and better through plane spatial resolution, SR allows to perform CC biometry more frequently than T2WS.

Emerging and re-emerging infectious diseases in pregnant women in an amazonian region :

Scientific paper ArODES

a large retrospective study from French Guiana

Najeh Hcini, Véronique Lambert, Jean-François Carod, Meredith Mathieu, Gabriel Carles, Olivier Picone, Jeanne Sibiude, Léo Pomar, Mathieu Nacher

European journal of clinical microbiology & infectious diseases, 2024, 43, 6, 1081-1090

Link to the publication

Summary:

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 the Maroni River over the previous nine years. Methods: This retrospective cohort study enrolled pregnant women living in west French Guiana territory and giving birth in the only local referral center after 22 weeks of gestation between 2013 and 2021. Data on symptomatic or asymptomatic biologically confirmed emerging or re-emerging diseases during pregnancy was collected. Results: Six epidemic waves were experienced during the study period, including 498 confirmed Zika virus infections (2016), 363 SARS-CoV-2 infections (2020–2021), 87 chikungunya virus infections (2014), 76 syphilis infections (2013–2021), and 60 dengue virus infections (2013–2021) at different gestational ages. Furthermore, 1.1% (n = 287) and 1.4% (n = 350) of pregnant women in west French Guiana were living with HIV and HTLV, respectively. During the study period, at least 5.5% (n = 1,371) faced an emerging or re-emerging infection during pregnancy. Conclusion: These results highlight the diversity, abundance, and dynamism of emerging and re-emerging infectious agents faced by pregnant women in the Amazon basin. Considering the maternal and neonatal adverse outcomes associated with these infections, increased efforts are required to enhance diagnosis, reporting, and treatment of these conditions.

Contribution of fetal blood sampling to determining the prognosis of congenital cytomegalovirus infections :

Scientific paper ArODES

a case-cohort study in Switzerland

Léo Pomar, Agathe Contier, Milos Stojanov, Cécile Guenot, Joanna Sichitiu, Anita C. Truttmann, Yvan Vial, David Baud

American journal of obstetrics and gynecology, 2024, 231, 6, 643.e1-643.e12

Link to the publication

Summary:

BACKGROUND: Cytomegalovirus is responsible for the most common congenital infection, affecting 0.5% to 1.0% of live births in Europe. Congenital cytomegalovirus infection can be diagnosed during pregnancy by viral DNA amplification in the amniotic fluid, but the prognosis of fetuses without severe brain abnormalities remains difficult to establish on the basis of prenatal imaging alone. OBJECTIVE: To identify predictors of moderate to severe symptomatic cytomegalovirus infection among fetal blood parameters and to propose an algorithm on the basis of these parameters and on prenatal imaging that would provide the best positive and negative predictive values. STUDY DESIGN: Fetal blood sampling at 21e28 weeks gestation was performed in fetuses with congenital cytomegalovirus infection confirmed by amniocentesis after maternal infection in the first-trimester or periconceptional period. We compared the levels of hemoglobin, thrombocytes, g-glutamyl transpeptidase, aspartate aminotransferase, alanine aminotransferase, b2-microglobulin, immunoglobulins G and M, and cytomegalovirus DNA viral loads in amniotic fluid and fetal blood between those with moderate to severe symptomatic infection and those with asymptomatic to mild infection (median follow-up of 36 months for live births). RESULTS: Among 58 fetuses included, 25 (43%) had a moderate to severe symptomatic infection: 16 with severe cerebral abnormalities, 5 with multiple signs or symptoms at birth, 2 with bilateral sensorineural hearing loss, and 2 with neurodevelopmental delay. The values of thrombocytes, aspartate aminotransferase, b2 microglobulin, Immunoglobulin M, and cytomegalovirus viral loads differed significantly between fetuses with moderate to severe symptomatic infection and those with asymptomatic to mild infection. The optimal strategy to predict moderate to severe symptomatic infection was to first perform fetal brain imaging, followed by fetal blood sampling with the following cutoffs: thrombocytes <120,000/mL, viremia 5 log10/mL, and b2 microglobulin 12 mg/L). This recursive algorithm had a negative predictive value of 100% for moderately to severely symptomatic infection. CONCLUSION: The combination of thrombocytes, b2-microglobulin, and cytomegalovirus viral load in fetal blood can be used for prognosis determination, particularly in cytomegalovirus-infected fetuses without severe brain abnormalities at the time of prenatal diagnosis. Future studies should evaluate whether these parameters remain useful in infected fetuses who have been treated with valacyclovir before fetal blood sampling.

Prenatal and postnatal ocular abnormalities following congenital zika virus infections :

Scientific paper ArODES

a systematic review

Anis Mahmoud, Léo Pomar, Véronique Lambert, Olivier Picone, Najeh Hcini

Ocular immunology and inflammation, 2024, 23, 9, 2217-2227

Link to the publication

Summary:

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 = 24) periods were included in the analysis. In the prenatal period, the most common ocular findings were intraocular calcification cases (4/6, 66.6%) and microphthalmia (3/6, 50%). Postnatal ocular abnormalities of congenital ZIKV infection were described after birth in 479 cases. Among them microphthalmia was reported in 13 cases (13/479, 2.7%). Posterior segment (retina and optic nerve) was the most affected structure, consisting of pigmentary changes (229/479, 47.8%), macular chorioretinal atrophy (216/479, 45%), optic nerve atrophy (181/479, 37.8%), increased cup-to-disk ratio (190/479, 39.6.%), optic nerve hypoplasia (93/ 479,19.4%), vascular changes (26/479, 5.4%), and retinal coloboma (20/479, 4.1%). The anterior segment was involved in 4.6% (22/479) of cases, including cataract (9/479, 1.8%), lens subluxation (1/479, 0.2%), iris coloboma (5/479, 1%), and congenital glaucoma (7/479, 1.4%). These ocular anomalies were isolated in one case (1/479, 0.2%) and multiple anomalies were found in the other cases. Long-term visual disorders have been described, with no possible improvement and even a worsening of some of the ocular anomalies previously observed. No reactivation of ocular lesions was observed. Conclusion: This review highlights the severe ocular abnormalities associated with congenital ZIKV infections. The importance of multidisciplinary communication between the obstetrician, the maternal-fetal medicine specialist, and the ophthalmologist is emphasized. Protocol registration: This systematic review was registered with the International Prospective Register of Systematic Reviews (PROSPERO), registration440 188.

Cytomegalovirus infection during pregnancy :

Scientific paper ArODES

cross-sectional survey of knowledge and prevention practices of healthcare professionals in French-speaking Switzerland

Pauline Sartori, David Baud, Begona Martinez de Tejada, Alexandre Farin, Marie-Claude Rossier, Adrien Bruno, Léo Pomar

Virology journal, 2024, 21, 1, art. 45

Link to the publication

Summary:

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 well as the sociodemographic-professional factors that influence them. Methods: This observational study used a cross-sectional design to collect data-via an anonymous electronic questionnaire in French distributed to gynecologists-obstetricians, general practitioners and midwives via various channels: e-mails and social networks of partner centers, professional associations, and conferences. The 41-item questionnaire collected data on sociodemographic and professional characteristics, general CMV knowledge, national recommendation knowledge and prevention practices. Univariable and multivariable analyses were performed. Results: A total of 110 gynecologist-obstetricians, 5 general practitioners and 226 midwives participated in the study. While more than 80% of practitioners were familiar with protective hygiene measures, significant gaps were highlighted concerning the transmission routes, as well as the signs of short- and long-term congenital CMV infection. Regarding practice, 63.3% of participants provided information on CMV to their patients, mainly during the first antenatal visit. Among those who did not, lack of knowledge and forgetfulness were the two main reasons cited. Concerning systematic screening, 45.7% of participants offered it to their patients, and 37.3% only offered it to “at risk” groups. The existence of national guidelines on CMV was known by 62.0% of participants. Multivariable analysis revealed that working as a gynecologist-obstetrician was independently associated with higher score of preventive practices, while performing ultrasound or preconception consultations was independently associated with a higher score of general CMV knowledge, and working in a university hospital was independently associated with a higher score of Swiss recommendation knowledge. A level of training higher than the basic medical or midwifery diploma and participation in fetal medicine symposia both promote a higher score of CMV knowledge and prevention practices in line with current recommendations. Conclusion: This study confirms the significant gaps in CMV knowledge among French-speaking Swiss caregivers along with the heterogeneity of their prevention practices. To raise awareness among pregnant women and reduce the burden of congenital CMV infections, improving professional knowledge through access to specific training and standardizing practices should be a national priority.

Arboviruses and pregnancy :

Scientific paper ArODES

are the threats visible or hidden?

Najeh Hcini, Véronique Lambert, Olivier Picone, Jean-François Carod, Gabriel Carles, Léo Pomar, Loïc Epelboin, Mathieu Nacher

Tropical diseases, travel medicine and vaccines, 2024, 10, 1, art. 4

Link to the publication

Summary:

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. Recently and since the 2016 Zika virus outbreak, there has been a newfound interest in these diseases. Through various neuropathogenic, visceral, placental, and teratogenic mechanisms, these arbovirus infections can lead to fetal losses, obstetrical complications, and a wide range of congenital abnormalities, resulting in long-term neurological and sensory impairments. Climate change, growing urbanization, worldwide interconnectivity, and ease of mobility allow arboviruses to spread to other territories and impact populations that had never been in contact with these emerging agents before. Pregnant travelers are also at risk of infection with potential subsequent complications. Beyond that, these pathologies show the inequalities of access to care on a global scale in a context of demographic growth and increasing urbanization. It is essential to promote research, diagnostic tools, treatments, and vaccine development to address this emerging threat. Background : The vulnerability of pregnant women and fetuses to emergent and re-emergent pathogens has been notably illustrated by the outbreaks of Zika virus. Our comprehension of the complete scope and consequences of these infections during pregnancy remains limited, particularly among those involved in perinatal healthcare, such as obstetricians and midwives. This review aims to provide the latest information and recommendations regarding the various risks, management, and prevention for pregnant women exposed to arboviral infections.

2023

Causes and consequences of fever in Amazonian pregnant women :

Scientific paper ArODES

a large retrospective study from French Guiana

Najeh Hcini, Véronique Lambert, Olivier Picone, Jean-Francois Carod, Mérédith Mathieu, Romane Cousin, Ferroudja Akli, Gabriel Carles, Célia Basurko, Léo Pomar, Loïc Epelboin, Mathieu Nacher

PLOS neglected tropical diseases, 17, 10, art. e0011721

Link to the publication

Summary:

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. Postpartum fever and nosocomial infections were excluded. We focused on medical history and on clinical and biological findings. Causes were characterized as confirmed or uncertain and then classified as preventable or non-preventable. Results: A total of 940 pregnant women who experienced at least one episode of fever were included and compared to 23,811 deliveries who occurred during the same period without documented fever. Among them, 43.7% (411/940) were in labor. About 3.7% (35/940) of febrile pregnant women had at least two episodes of fever, while 0.3% (3/940) had a coinfection at the time of diagnosis, resulting in a total of 978 febrile episodes. Among them, causes remained unknown or uncertain in 7.6% (75/978) and 0.9% (9/978) of cases, respectively. Among confirmed causes of fever throughout pregnancy (n = 483), the most common known cause was arbovirus infection (146/483, 30.2%), followed by urinary tract infection (134/483, 27.7%), chickenpox (27/483, 5.6%), and gastrointestinal (14/483, 2.9%) and pulmonary infections (10/483, 2%). Mothers with fever had a higher risk of cesarean section (19.8% vs 15.5%, aOR 1.3 [95% CI 1.14–1.6], stillbirth (5.5% versus 1.9%, aOR 2.7 [95% CI 2–3.7]), and preterm delivery < 34 weeks of gestation (7.2% vs 4.7%, aOR 1.5 [95% CI1.2–2]. Conclusions: In the Amazon region, causes of fever are diverse and often associated with epidemic waves, notably arboviruses. This must be considered when exploring possible causes of fever during pregnancy in these localities, including fetal anomalies and/or fetal loss. Physicians should consider the epidemiological context and avoid generalizations. Given the impact of emergent agents such as arboviruses on pregnancy, particular attention must be paid to the epidemiological context. This study can also help clinicians when managing fever in pregnant travelers or in their partner after having visited exposed areas. In this context, fetal abnormalities and adverse obstetric outcomes should be explored accordingly.

Diagnostic prénatal :

Professional paper ArODES

le rôle des sages-femmes

Léo Pomar, Marie Blanchard

Obstetrica, 10, 48-51

Link to the publication

Summary:

Lorsqu’une femme enceinte se trouve confrontée à la possibilité d’une anomalie foetale, le soutien et l’accompagnement des professionnel·le·s de santé sont essentiels pour l’aider à prendre des décisions éclairées. Dans ce domaine, les sages-femmes, tant dans leur rôle en diagnostic prénatal que dans l’accompagnement des familles confrontées à la décision d’interrompre une grossesse ou d’accueillir un enfant différent, jouent un rôle crucial.

Editorial

Professional paper ArODES

Léo Pomar

Obstetrica, 7, 37

Link to the publication

Prenatal diagnosis of Gómez-López-Hernández syndrome

Scientific paper ArODES

Léo Pomar, Wawrzyniec Rieder, Estelle Dubruc, Fabienne Giuliano, Isis Atallah, Sébastien Lebon, Yvan Vial

Fetal diagnosis and therapy, 50, 2, 92-97

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Summary:

Gómez-López-Hernández syndrome (GLHS), also known as cerebello-trigeminal-dermal dysplasia, is an extremely rare neurocutaneous 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, including craniofacial and supratentorial anomalies, as well as neurodevelopmental issues. Case Presentation: Here, we present a case of antenatally diagnosed GLHS with RES, hydrocephaly, and craniofacial anomalies identified on ultrasound (low-set ears with posterior rotation, hypertelorism, midface hypoplasia, micrognathia, and anteverted nares) which were confirmed by autopsy after termination of pregnancy at 23 weeks of gestation. Discussion: As no known genetic causes have been identified and the classical triad is not applicable to prenatal imaging, prenatal diagnosis of GLHS is based on neuroimaging and the identification of supporting features. In presence of an RES associated with craniofacial abnormalities in prenatal (brachycephaly, turricephaly, low-set ears, midface retrusion, micrognathia), GLHS should be considered as “possible” according to postnatal criteria.

Risk of congenital malformation following first trimester mRNA COVID-19 vaccine exposure in pregnancy :

Scientific paper ArODES

the COVI-PREG prospective cohort

Guillaume Favre, Emeline Maisonneuve, Léo Pomar, Charlotte Daire, Cécile Monod

Clinical microbiology and infection, 29, 10, 1306-1312

Link to the publication

Summary:

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 time of COVID-19 vaccination. Pregnant women exposed to at least one dose of mRNA COVID-19 vaccine from conception to 11 weeks of gestations and 6 days were compared to pregnant women exposed to the vaccine from 12 weeks to the end of pregnancy. The primary outcome was a confirmed congenital malformation at birth. RESULTS: a total of 1450 pregnant women were enrolled including 124 in the first trimester and 1326 in the second and third trimester. The overall proportion of congenital malformation was 0.81% (n=1/124;95%CI 0.02-4.41) and 0.83% (n=11/1326; 95% CI 0.41-1.48) among pregnant exposed to the COVID-19 vaccine during the first and second/third trimester, respectively. First trimester exposure was not associated with a higher risk of congenital malformation with a relative risk (RR) of 0.89 (95%CI 0.12-6.80) with no significant changes after adjustment through exploratory analysis. CONCLUSION: pregnant women exposed to mRNA COVID-19 vaccine before 12 weeks of gestation did not have an increased risk of congenital malformation compared to women exposed outside the teratogenic window. As vaccination is safe and effective, emphasis must be placed on promoting vaccination during pregnancy.

How to differentiate PHACES syndrome from Blake pouch cyst in first half of pregnancy :

Scientific paper ArODES

letter to the editor

Léo Pomar, Sébastien Lebon, Yvan Vial

Ultrasound in obstetrics gynecology, 62, 6, 906-908

Link to the publication

Datamama, bringing pregnancy research into the future :

Scientific paper ArODES

design, development, and evaluation of a citizen science pregnancy mobile application

Eva Gerbier, Yvan Vial, Jardena Puder, Amar Arhab, Antje Horsch, Valérie Avignon, Déborah Fort, Camille Deforges, Céline J. Fischer Fumeaux, Isabelle Henriot, Diana Pinto Pereira Goncalves, Léo Pomar, Guillaume Favre, Françoise Damnon, Hélène Legardeur, Gaëlle Mayor, Michael Ceulemans, Nohan Budry, Didier Page, Juergen Ehrensberger, Olivier Liechti, David Baud, Alice Panchaud

Frontiers in Drug Safety and Regulation, 2023, vol. 3, art. 1187023

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Summary:

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 Swiss pregnancy mobile app as an innovative means to collect research data and provide users with reliable information. Methods: Determining the key features of the app involved a review of the literature and assessment of popular apps in the Swiss AppStore. A team of engineers developed the app, which includes a pregnancy timeline, questionnaires for data collection, medical and psychological articles and a checklist with appointment reminders. The content was written and reviewed by healthcare providers considered experts in the topics adressed. The questionnaires are distributed based on the user’s gestational age, by a chatbot. The project was authorized by the ethics commission in the canton of Vaud. An online survey of ten questions, advertised on Datamama’s home screen, was conducted to assess the users’ use of the app (27.11- 19.12.2022). Results: A review of 84 articles and 25 popular apps showed the need for a comprehensive pregnancy app. The development of Datamama took 2 years and included the creation of 70 medical and psychological articles and 29 questionnaires covering 300 unique variables. Six months after the launch, there were 800 users with a 73% average participation rate in the questionnaires. Sixty-five women completed the survey, with 70.8% using the app once to multiple times per week. The primary reason for using the app was to help research by answering the questionnaires, followed by access to reliable medical information. The reason most frequently ranked first for using the app was to help research by answering the questionnaires (42/65, 67% of women rated it first), followed by access to reliable medical information (34/65, 54% women rated it second). Women rated the information as clear, understandable, and interesting with a trust rating in data handling at 98.5%. The average grade for recommending the app was 8/10, with suggestions for increasing the amount of medical content and tailoring it based on gestational age. Conclusion: Datamama is the first pregnancy app to address the needs of both patients and researchers. Initial feedback from users was positive, highlighting future challenges for success. Future work will consist in improving the app, validating the data and use it to answer specific pregnancy-related research questions.

Determinants of vaccination and willingness to vaccinate against COVID-19 among pregnant and postpartum women during the third wave of the pandemic :

Scientific paper ArODES

a European multinational cross-sectional survey

Emeline Maisonneuve, Eva Gerbier, Fatima Tauqeer, Léo Pomar, Guillaume Favre

Viruses, 2023, vol. 15, no. 5, art. 1090

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Summary:

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 conducted in Belgium, Norway, Switzerland, The Netherlands, and United Kingdom (UK) in June–August 2021. Among 3194 pregnant women, the proportions of women vaccinated or willing to be vaccinated ranged from 80.5% in Belgium to 21.5% in Norway. The associated characteristics were country of residence, chronic illness, history of flu vaccine, trimester of pregnancy, belief that COVID-19 is more severe during pregnancy, and belief that the COVID-19 vaccine is effective and safe during pregnancy. Among 1659 postpartum women, the proportions of women vaccinated or willing to be vaccinated ranged from 86.0% in the UK to 58.6% in Switzerland. The associated determinants were country of residence, chronic illness, history of flu vaccine, breastfeeding, and belief that the COVID-19 vaccine is safe during breastfeeding. Vaccine hesitancy in the obstetric population depends on medical history and especially on the opinion that the vaccine is safe and on the country of residence.

Maternal and perinatal outcomes following pre-Delta, Delta, and Omicron SARS-CoV-2 variants infection among unvaccinated pregnant women in France and Switzerland :

Scientific paper ArODES

a prospective cohort study using the COVI-PREG registry

Guillaume Favre, Emeline Maisonneuve, Léo Pomar

The lancet regional health, March 2023, vol. 26, art. 100569

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Summary:

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 prospective study enrolled women from March 2020 to September 2022. Exposure to the different SARS-CoV-2 variants was defined by their periods of predominance. The primary outcome was severe maternal adverse outcome defined as either intensive care unit admission, acute respiratory distress syndrome, advanced oxygen supplementation, or maternal death. The secondary outcomes were preterm birth and other perinatal outcomes. Findings Overall, 1402, 262, and 391 SARS-CoV-2 positive pregnant women were enrolled during the pre-Delta, Delta, and Omicron periods respectively. Severe maternal adverse outcome was reported in 3.4% (n = 947/1402; 95% confidence intervals (95%CI) 2.5–4.5), 6.5% (n = 7/262; 95%CI 3.8–10.2), and 1.0% (n = 4/391; 95%CI 0.3–2.6) of women during the pre-Delta, Delta, and Omicron periods. The risk of severe maternal adverse outcome was higher during the Delta vs pre-Delta period (adjusted risk ratio (aRR) = 1.8; 95%CI 1.1–3.2) and lower during the Omicron vs pre-Delta period (aRR = 0.3; 95%CI, 0.1–0.8). The risks of hospitalization for COVID-19 were 12.6% (n = 176/1402; 95%CI 10.9–14.4), 17.2% (n = 45/262; 95%CI 12.8–22.3), and 12.5% (n = 49/391; 95%CI 9.4–16.2), during the pre-Delta, Delta, and Omicron period, respectively. Pregnancy complications occurred after SARS-CoV-2 exposure in 30.0% (n = 363/1212; 95%CI 27.4–32.6), 35.2% (n = 83/236; 95%CI 29.1–41.6), and 30.3% (n = 105/347; 95%CI 25.5–35.4) of patients during the pre-Delta, Delta, and Omicron periods, respectively. Stillbirths were reported in 0.5% (n = 6/1159; 95%CI 0.2–1.1), 2.8% (n = 6/210; 95%CI 1.0–6.0), and 0.9% (n = 2/213; 95%CI 0.1–3.4) or patients during the pre-Delta, Delta, and Omicron periods respectively. Interpretation The Delta period was associated with a higher risk of severe maternal adverse outcome and the Omicron period with a lower risk of severe adverse outcome compared to pre-Delta era. The reported risk of hospitalization was high during the Omicron period and should not be trivialized.

Primary, secondary, and tertiary prevention of congenital cytomegalovirus infection

Scientific paper ArODES

Pauline Sartori, Charles Egloff, Najeh Hcini, Christelle Vauloup Fellous, Claire Périllaud-Dubois, Olivier Picone, Léo Pomar

Viruses, 2023, vol. 15, no. 4, art. 819

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Summary:

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 efficacy of these strategies, including educating pregnant women and women of childbearing age on their knowledge of hygiene measures, development of vaccines, screening for cytomegalovirus infection during pregnancy (systematic versus targeted), prenatal diagnosis and prognostic assessments, and preventive and curative treatments in utero.

Emerging viral infections in pregnancy :

Scientific paper ArODES

what’s new in 2022 ? : editrorial

Léo Pomar, David Baud

Viruses, 2023, vol. 15, no. 4, art. 889

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Incidence, causes, and risk factors of stillbirth in an Amazonian context :

Scientific paper ArODES

Saint Laurent du Maroni maternity ward 2016–2021

Meredith Mathieu, Véronique Lambert, Gabriel Carles, Olivier Picone, Jean-François Carod, Léo Pomar, Mathieu Nacher, Najeh Hcini

European journal of obstetrics gynecology and reproductive biology: X, 2023, vol. 18, art. 100190

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Summary:

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 Western French Guiana Hospital Center was extracted. Terminations of pregnancy were excluded. We focused on medical history, clinical investigation, biological findings, placental histology, and autopsy examination to elucidate the cause of death. We used the Initial Cause of Fetal Death (INCODE) classification system for assessment. Univariable and multivariable logistic regression analyses were performed. Results: Overall, 331 fetuses in 318 stillbirth deliveries were reviewed and compared to live births that occurred during the same period. The rate of fetal death varied between 1.3 % and 2.1 %, with an average of 1.8 % over the 6-year period. Poor antenatal care (104/318, 32.7 %), obesity ≥30 kg/m2 (88/318, 31.7 %), and preeclampsia (59/318, 18.5 %) were the main risk factors associated with fetal death in this group. Four hypertensive crises were reported. According to the INCODE classification, the main causes of fetal death were obstetric complications (112/331, 33.8 %), particularly intrapartum fetal death with labor-associated asphyxia under 26 weeks (64/112, 57.1 %), and placental abruption (29/112, 25.9 %). Maternal-fetal infections were common, particularly mosquito-borne diseases (e.g., Zika virus, dengue, and malaria), re-emerging infectious agents such as syphilis, and severe maternal infections (8/331, 2.4 %). 19.3 % of fetal deaths (64/331) remained unexplained. Conclusion: Change in lifestyle as well as social deprivation and isolation adversely affect pregnancy in western French Guiana, in the context of a poor health care system that is similar to what is found in the Amazonian basin. Particular attention must be paid to emerging infectious agents in pregnant women and travelers returning from the Amazon region.

2022

Impact of the first wave of the COVID-19 pandemic on birth rates in Europe :

Scientific paper ArODES

a time series analysis in 24 countries

Léo Pomar, Guillaume Favre, Claire De Labrusse, Agathe Contier, Michel Boulvain, David Baud

Human reproduction, December 2022, vol. 37, no. 12, pp. 2921–2931,

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Summary:

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), compared to the average number of live births in January 2018 and 2019. WHAT IS KNOWN ALREADY Previous pandemics in the 20th and 21st centuries have been associated with a decline in birth rates 9 months after their peak, and a rebound in births over time. Lockdowns were necessary to control the first wave of the COVID-19 pandemic and may have had an impact on subsequent birth rates. STUDY DESIGN, SIZE, DURATION Monthly time series data on live births from January 2018 to March 2021 were extracted to provide a time-series analysis of birthrates during and after the first wave of the COVID-19 pandemic in 24 European countries. PARTICIPANTS/MATERIALS, SETTING, METHODS We conducted a random-effect generalized least squares regression to assess the seasonality of births from January 2018 to March 2021, and to identify potential differences in monthly live births after the first wave of the COVID-19 pandemic, considering the seasonality of births. To quantify these potential differences, we estimated the variation rate between the monthly live births observed during 2020 and 2021 and the mean of the 2018–2019 monthly live births in Europe. Factors potentially associated with a variation in monthly birth rates were assessed using univariable and multivariable generalized linear regressions. MAIN RESULTS AND THE ROLE OF CHANCE When considering the seasonality of births, January 2021 was the only month with a significant difference in live births. A drop of −14.1% was observed compared to the average number of live births in January 2018 and 2019. At the national level, this drop was observed 9–10 months after the epidemic peaks in 13 countries. The duration of lockdowns was the variable that had the stronger association with this decrease, whereas higher incomes per capita could be a factor limiting this decline. A rebound in births compared to the previous years occurred in March 2021 in 13 countries. LIMITATIONS, REASONS FOR CAUTION Our data are based on national data, limiting the power in the multivariable models used and the identification of other potential factors contributing to a decrease or an increase in birth rates. In addition, we collected only live births up to April 2021, which precludes the identification of a difference in births seasonality in 2021. WIDER IMPLICATIONS OF THE FINDINGS As with previous pandemics, the COVID-19 outbreak was associated with a decline in births 9 months after its first wave. This trend may be associated with the duration of the lockdowns. Although there was a rebound in births in the following months, it does not seem to compensate for this decline. STUDY FUNDING/COMPETING INTEREST(S) The authors receive no external funding and have no conflict of interest to declare. TRIAL REGISTRATION NUMBER N/A.

Prenatal diagnosis of congenital lymphocytic choriomeningitis virus infection :

Scientific paper ArODES

a case report

Fanny Tevaearai, Laureline Moser, Léo Pomar

Viruses, 2022, vol. 14, no. 11, art. 2586

Link to the publication

Summary:

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 case report of congenital LCMV infection, including fetal imaging, confirmed by positive LCMV IgM in fetal blood and cerebrospinal fluid.

COVID-19-related medicine utilization study in pregnancy :

Scientific paper ArODES

the COVI-PREG cohort

Guillaume Favre, Eva Gerbier, Emeline Maisonneuve, Léo Pomar, COVI-PREG and CONSIGN group

British journal of clinical pharmacology, May 2023, vol. 89, no. 5, pp. 1560-1574

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Summary:

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 2020to July 2021 were included using the COVI-PREG registry. Exposure to the followingCOVID-19-related medicines was recorded: antibiotics, antivirals, hydroxychloro-quine, corticosteroids, anti-interleukin-6 and immunoglobulins. We described theprevalence of medicines used, by trimester of pregnancy, maternal COVID-19 sever-ity level and early/late period of the pandemic (before and after 1 July 2020).Findings: We included 1964 pregnant patients who tested positive for SARS-CoV-2.Overall, 10.4% (205/1964) received at least one COVID-19-related medicine includ-ing antibiotics (8.6%; 169/1694), corticosteroids (3.2%; 62/1964), antivirals (2.0%;39/1964), hydroxychloroquine (1.4%; 27/1964) and anti-interleukin-6 (0.3%;5/1964). The use of at least one COVID-19-related medicine was 3.1% (12/381) in asymptomatic individuals, 4.2% (52/1233) in outpatients, 19.7% (46/233) in in patients without oxygen, 72.1% (44/61) in those requiring standard oxygen, 95.7%(22/23) in those requiring high flow oxygen, 96.2% (25/26) in patients who required intubation and 57.1% (4/7) among patients who died. The proportion who received medicines to treat COVID-19 was higher before than after July 2020 (16.7%vs.Received: 12 July 2022 Revised: 23 September 2022 Accepted: 6 November 2022DOI: 10.1111/bcp.15611Br J Clin Pharmacol.2023;1–15.wileyonlinelibrary.com/journal/bcp© 2022 British Pharmacological Society.17.7%). Antibiotics, antivirals and hydroxychloroquine had lower rates of use during the late period. Conclusion: Medicine use in pregnancy increased with disease severity. The trend towards increased use of corticosteroids seems to be aligned with changing guidelines. Evidence is still needed regarding the effectiveness and safety ofCOVID-19-related medicines in pregnancy.

Monkeypox and pregnancy :

Scientific paper ArODES

latest updates

Alexandre Cuérel, Guillaume Favre, Manon Vouga, Léo Pomar

Viruses, November 2022, vol. 14, no. 11, art. 2520

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Summary:

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 number of single-nucleotide polymorphisms found in the 2022 MPXV strain could indicate an accelerated human adaptation. Very little is known about the risks of an infection during pregnancy for both the mother and the fetus. Further observations must be made to create clear, adapted, evidence-based guidelines. This article summarizes the current knowledge about MPXV infections and similar pregnancy virus infections.

Mental health in pregnant individuals during the COVID-19 pandemic based on a Swiss online survey

Scientific paper ArODES

Guillaume Favre, Cléa Kunz, Simone Schwank, Ho-Fung Chung, Anda Petronela Radan, Luigi Raio, Mihaela Fluri, Ursula Winterfeld, David Baud, Léo Pomar

Scientific reports, 2022, vol. 12, no. 1, art. 18448

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Summary:

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 (GAD-7), and Impact Event Scale-Revised (IES-R) were evaluated and used to defined mental health impairment as a composite outcome. From October, 2020 to February, 2021, 736 participants responded. The anxiety GAD-7 score was moderate in 9.6% and severe in 2.0%. The EPDS was moderate in 21.5% and severe in 32.9%. The IES-R was moderate in 10.3% and severe in 3.9%. Mental health impairment was reported in 37.0%. The association between the risk of mental health impairment and foreign nationality was significant (OR = 1.48; 95%CI [1.06–2.05]) as well as fetal and pregnancy worries because of coronavirus (OR = 1.46; 95% CI [1.08–1.98]) and 1.65; 95% CI [1.22–2.24]). Adjusted ORs were significant for foreign nationality (aOR = 1.51; 95%CI [1.07–2.13]) and pregnancy worries because of coronavirus (aOR = 1.62; 95%CI [1.10–2.40]). Pregnant people and especially foreign national have a high risk of mental health impairment during the pandemic.

Monkeypox infection during pregnancy :

Scientific paper ArODES

european registry to quantify maternal and fetal risks : letter to the Editor

Léo Pomar, G. Favre, D. Baud

Ultrasound in obstetrics gynecology, September 2022, vol. 60, no. 3, p. 431

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Comment to “Pregnancy and COVID-19, focus on vaccine and pharmacological treatment”

Scientific paper ArODES

Michael Ceulemans, Laure Sillis, Veerle Foulon, Alice Panchaud, Ursula Winterfeld, Léo Pomar, Brian Cleary, Fergal O’Shaughnessy, Anneke Passier, Jonathan Luke Richardson, Hedvig Nordeng

Journal of reproductive immunology, August 2022, vol. 152, art.103639

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COVID-19 mRNA vaccine in pregnancy :

Scientific paper ArODES

results of the Swiss COVI-PREG registry, an observational prospective cohort study

Guillaume Favre, Emeline Maisonneuve, Léo Pomar, Ursula Winterfeld, Charlotte Daire, Dominique Delecraz, Sonia Campelo, Mirjam Moser, Monya Todesco-Bernasconi, Stefanie Sturm, Irene Hösli, Cécile Monod, Brigitte Frey Tirri, Stylianos Kalimeris, Carolin Blume, Jérôme Mathis, Roland Zimmerman, Anda Petronela Radan, Daniel Surbek, David Baud, Alice Panchaud

The lancet regional health - Europe, July 2022, vol. 18., art. 100410

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Summary:

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. Methods : This multicentre prospective cohort study describes early adverse events and perinatal outcomes in pregnant women who received at least one dose of mRNA vaccine between March 1st and December 27th, 2021 in Switzerland, using the COVI-PREG registry. Early adverse events were collected at least one month following vaccine administration. Pregnancy and neonatal outcomes were extracted from medical records using the maternity discharge letters providing follow-up information up to 5 days after birth. Findings : Of 1012 vaccinated women, 894 (88·3%) received both injections during pregnancy, with BNT162b2 (n = 271) or mRNA-1273 (n = 623) vaccines. Local events (mainly local pain) were reported in 81·3% and 80·5% after the first and second doses. Rates of systemic reactions (mainly fatigue and headache) were similar after the first dose and most frequent after the second dose of mRNA-1273. Of the 1012 women, four (0·4%; 95%CI [0·1-1·0]) severe early adverse events occurred: pulmonary embolism, preterm premature rupture of membranes, isolated fever with hospitalisation, and herpes zoster. Of 107 patients vaccinated before 14 weeks, one (0·9%; 95%CI [0·0-5·1]) early spontaneous abortions was reported (8 weeks). Of 228 vaccinated before 20 weeks one (0·4%; 95%CI [0·0-2·4]) late spontaneous abortion was reported (16 weeks). Of 513 women exposed before 37 weeks, 33 (6·4%; 95%CI [4·5-8·9]) delivered preterm. Among 530 patients exposed in pregnancy, no stillbirth was reported and 25 (4·7%; 95%CI [3·0-6·8]) neonates were admitted to intensive care unit. Interpretation : Frequent local and systemic effects were described after exposure to mRNA COVID-19 vaccines during pregnancy but severe events were rare. Women vaccinated during pregnancy did not experience higher adverse pregnancy or neonatal outcomes when compared to historical data on background risks in the obstetric population. Funding : This research was funded by a grant from the Swiss Federal Office of Public Health and the CHUV Foundation.

Prenatal diagnosis of Aicardi syndrome based on a suggestive imaging pattern :

Scientific paper ArODES

a multicenter case-series

Léo Pomar, José Ochoa, Sara Cabet, Thierry A. G. M. Huisman, Dario Paladini, Philipp Klaritsch, Aurore Galmiche, Florian Prayer, Sebastián Gacio, Karina Haratz, Gustavo Malinger, Tim Van Mieghem, David Baud, Bryann Bromley, Sébastien Lebon, Estelle Dubruc, Yvan Vial, Laurent Guibaud

Prenatal diagnosis, April 2022, vol. 42, no. 4, pp. 484-494

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Summary:

Objectives To characterize a suggestive prenatal imaging pattern of Aicardi syndrome using ultrasound and MR imaging. 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 imaging pattern highly suggestive of the diagnosis. Results Among 20 cases included, arachnoid cysts associated with a distortion of the interhemispheric fissure were constantly encountered associated with complete or partial agenesis of the corpus callosum (19/20, 95%). This triad in the presence of other CNS disorganization, such as polymicrogyria (16/17, 94%), heterotopias (15/17, 88%), ventriculomegaly (14/20, 70%), cerebral asymmetry [14/20, 70%]) and less frequently extra-CNS anomaly (ocular anomalies [7/11, 64%], costal/vertebral segmentation defect [4/20, 20%]) represent a highly suggestive pattern of Aicardi syndrome in a female patient. Conclusion Despite absence of genetic test to confirm prenatal diagnosis of AS, this combination of CNS and extra-CNS fetal findings allows delineation of a characteristic imaging pattern of AS, especially when facing dysgenesis of the corpus callosum.

Self-reported medication use among pregnant and postpartum women during the third wave of the COVID-19 pandemic :

Scientific paper ArODES

a European multinational cross-sectional study

Eva Gerbier, Guillaume Favre, Fatima Tauqeer, Ursula Winterfeld, Milos Stojanov, Alison Oliver, Anneke Passier, Hedvig Nordeng, Léo Pomar, David Baud, Alice Panchaud, Carla Meyer-Massetti, Michael Ceulemans

International journal of environmental research and public health, May 2022, vol. 19, no. 9, art. 5335

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Summary:

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 June–August 2021. Pregnant women or women who had delivered in the three preceding months, and ≥18 years old, could participate. The prevalence of overall medication use, self-medication, and changes in chronic medication use were determined. A total of 2158 women out of 5210 participants (41.4%) used at least one medication. Analgesics (paracetamol), systemic antihistamines (cetirizine), and drugs for gastric disorders (omeprazole) were the three most used classes. Anti-infectives were less prevalent than during pre-pandemic times. Antidepressants and anxiety related medication use remained similar, despite a higher prevalence of these symptoms. Self-medication was reported in 19.4% of women, and 4.1% of chronic medication users reported that they changed a chronic medication on personal initiative due to the pandemic. In conclusion, medication use patterns in our cohort were mostly similar to those of the first COVID-19 wave and the pre-pandemic period. More studies are needed to explore factors associated with self-medication and changes in chronic medication use due to the pandemic in this perinatal population.

Self-reported medication use among pregnant and breastfeeding women during the COVID-19 pandemic :

Scientific paper ArODES

a cross-sectional study in five european countries

Michael Ceulemans, Verlee Foulon, Alice Panchaud, Ursula Winterfeld, Léo Pomar, Valentine Lambelet, Brian Cleary, Fergal O’Shaughnessy, Anneke Passier, Jonathan Luke Richardson, Hedvig Nordeng

International journal of environmental research and public health, January 2022, vol. 19, no. 3, art. 1389

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Summary:

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 breast-feeding women during the first pandemic wave. Factors associated with medication use were estimated by logistic regression. In total, 8378 women participated (i.e., 3666 pregnant and 4712 breastfeeding women). Most responses were collected in Norway (34%) and The Netherlands (28%), followed by Switzerland (19%), Ireland (17%) and UK (2%). Participants were more often professionally active and more often had a higher educational level compared to the general birthing population in each country. Overall, approximately 60% of women reported having used at least 1 medication in the preceding 3 months. Daily and occasional use was reported by 34% and 42% of pregnant and 29% and 44% of breastfeeding women. The most prevalent ATC (Anatomical Therapeutic Chemical) categories were the nervous system, the respiratory system, the alimentary tract/metabolism, and the musculo-skeletal system. Paracetamol, ibuprofen, antacids, and cetirizine were the most frequently used medications. The rate of antibacterial use was lower than previously reported. Having a chronic illness, country, maternal age, SARS-CoV-2 testing, professional status and time since delivery were associated with medication use. In conclusion, perinatal medication use was highly prevalent during the first pandemic wave, underlining the importance of maintaining counseling efforts on medication use, even in times of disrupted healthcare services and/or limited resources.

Special issue "Emerging virus infections in adverse pregnancy outcomes" :

Scientific paper ArODES

editorial

Léo Pomar, David Baud

Viruses, 2022, Vol. 14, No. 2, Art. 285

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2021

Decreased fetal movements :

Scientific paper ArODES

a sign of placental SARS-CoV-2 infection with perinatal brain injury

Guillaume Favre, Sara Mazzetti, Carole Gengler, Claire Bertelli, Juliane Schneider, Bernard Laubscher, Romina Capoccia, Fatemeh Pakniyat, Inès Ben Jazia, Béatrice Eggel-Hort, Laurence de Leval, Léo Pomar, Gilbert Greub, David Baud, Eric Giannoni

Viruses, December 2021, vol. 12, no. 12, art. 2517

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Summary:

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 section at 29 + 3 and 32 + 1 weeks of gestation, and leading to brain injury. Placental examination revealed extensive and multifocal chronic intervillositis, with intense cytoplasmic positivity for SARS-CoV-2 spike antibody and SARS-CoV-2 detection by RT-qPCR. Vertical transmission was confirmed in one case, and both neonates developed extensive cystic peri-ventricular leukomalacia.

Impact of the COVID-19 pandemic on Swiss pregnant and breastfeeding women :

Scientific paper ArODES

a cross-sectional study covering the first pandemic wave

Valentine Lambelet, Michael Ceulemans, Hedvig Nordeng, Guillaume Favre, Antje Horsch, Milos Stojanov, Ursula Winterfeld, David Baud, Alice Panchaud, Léo Pomar

Swiss medical weekly, 2021, vol. 151, art. w30009

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Summary:

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 how this pandemic affected pregnant and breastfeeding women. Among women who completed the survey, 69.0% (1050/1518) indicated the first wave of the pandemic affected their personal habits, 61.0% (689/1131) were affected in their work and 40.0% (632/1573) reported impaired relations with healthcare services (different denominators correspond to the number of participants who answered the question). 36.8% (110/299) of women reported an impact of the pandemic on their current pregnancy experience or breastfeeding experience (8.2%, 46/555). Overall, 11.6% (170/1467) of participants who completed the validated screening tests for mental health symptoms (Edinburgh Postnatal Depression Scale, Generalized Anxiety Disorder 7, Perceived Stress Scale) presented a score compatible with symptoms of major depression, severe anxiety or high perceived stress, which is higher than in the pre-pandemic period according to literature. Risk factors independently associated with impaired mental health were being hospitalized, having symptoms of COVID-19, living with a person with COVID-19 symptoms, having comorbidities, having experienced reduced healthcare services, having restricted usual activities and being a housewife. Protective factors independently associated were a high level of education and living with a partner. Our findings suggest that the COVID-19 pandemic might have significantly affected the well-being and mental health of pregnant and breastfeeding women, directly in the case of exposure, and indirectly as a result of the potential modifications in their life habits and in healthcare facilities.

Current data on COVID-19 mRNA-vaccine safety during pregnancy might be subject to selection bias. Reply to Stroobandt, S.; Stroobandt, R. Data of the COVID-19 mRNA-vaccine V-safe surveillance system and pregnancy registry reveals poor embryonic and second trimester fetal survival rate. Comment on “Stuckelberger et al. SARS-CoV-2 Vaccine willingness among pregnant and breastfeeding women during the first pandemic wave: a cross-sectional study in Switzerland. Viruses 2021, 13, 1199”

Scientific paper ArODES

Sarah Stuckelberger, Guillaume Favre, Michael Ceulemans, Eva Gerbier, Valentine Lambelet, Milos Stojanov, Ursula Winterfeld, David Baud, Alice Panchaud, Léo Pomar

Viruses, August 2021, vol. 13, no. 8, art. 1546

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SARS-CoV-2 vaccine willingness among pregnant and breastfeeding women during the first pandemic wave :

Scientific paper ArODES

a cross-sectional study in Switzerland

Sarah Stuckelberger, Guillaume Favre, Michael Ceulemans, Hedvig Nordeng, Eva Gerbier, Valentine Lambelet, Milos Stojanov, Ursula Winterfeld, David Baud, Alice Panchaud, Léo Pomar

Viruses, July 2021, vol. 13, no. 7, Article 1199

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Summary:

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 become vaccinated against SARS-CoV-2 if a vaccine was available were evaluated through binary, multi-choice, and open-ended questions. Factors associated with vaccine willingness were evaluated through univariable and multivariable analysis. A total of 1551 women responded to questions related to the primary outcome. Only 29.7% (153/515) of pregnant and 38.6% (400/1036) of breastfeeding women were willing to get vaccinated against SARS-CoV-2 if a vaccine had been available during the first wave. Positive predictors associated with SARS-CoV-2 vaccine acceptance were an age older than 40 years, a higher educational level, history of influenza vaccination within the previous year, having an obstetrician as the primary healthcare practitioner, and being in their third trimester of pregnancy. After the first pandemic wave, Switzerland had a low SARS-CoV-2 vaccination acceptance rate, emphasizing the need to identify and reduce barriers for immunization in pregnant and breastfeeding women, particularly among the youngest and those with a lower educational level.

Emerging virus infections in adverse pregnancy outcomes :

Scientific paper ArODES

Special Issue

David Baud, Léo Pomar

Viruses, 2021, vol. 13, special issue

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Summary:

Viruses that emerged in the past decades, such as arboviruses and SARS-coronaviruses, are increasingly recognized as potential risk factors for adverse pregnancy outcomes. On the fetal side, arboviruses have proved their ability to cross the placental barrier, at different stages of pregnancy, and have been associated with fetal losses, fetal malformations (Zika, West Nile, and Venezuelan equine encephalitis viruses) and adverse neonatal outcomes (Dengue and Chikungunya viruses). The SARS-COV-2 has also be associated with rare maternal-fetal transmission and placental affection leading to fetal losses. More common viruses, like cytomegalovirus, are also well-known causes of fetal and childhood sequelae, and recent research on its prognosis factors and in-utero treatment may be welcome. On the maternal side, SARS-COV-2 might compromise maternal health, as well as Dengue viruses have been associated with high risks of adverse obstetrical outcomes, including maternal death, pre-eclampsia or post-partum hemorrhage. Thus, research on the maternal physiopathology would also be welcome. In this Special Issue of Viruses, we aim for original researchs, reviews and commentaries that contribute to an improved understanding of viral infection of placenta and fetal cells, or that report on the maternal and fetal outcomes after an emerging viral infection during pregnancy.

2023

Datamama, bringing pregnancy research into the future :

Conference ArODES

design, development, and evaluation of a citizen science pregnancy mobile application

Eva Gerbier, Yvan Vial, Jardena Puder, Olivier Le Dizes, Magali Andrey, Léo Pomar, Didier Page, Nohan Budry, Juergen Ehrensberger, Olivier Liechti

Gynecologic and obstetric investigation

Link to the conference

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PEOPLE@HES-SO Directory and Skills inventory

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