Olivier Irion

University of Geneva, Genève, Geneva, Switzerland

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Publications (93)346.75 Total impact

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    ABSTRACT: Macrosomic fetuses are at increased risk of shoulder dystocia. We aimed to compare induction of labour with expectant management for large-for-date fetuses for prevention of shoulder dystocia and other neonatal and maternal morbidity associated with macrosomia. We did this pragmatic, randomised controlled trial between Oct 1, 2002, and Jan 1, 2009, in 19 tertiary-care centres in France, Switzerland, and Belgium. Women with singleton fetuses whose estimated weight exceeded the 95th percentile, were randomly assigned (1:1), via computer-generated permuted-block randomisation (block size of four to eight) to receive induction of labour within 3 days between 37(+0) weeks and 38(+6) weeks of gestation, or expectant management. Randomisation was stratified by centre. Participants and caregivers were not masked to group assignment. Our primary outcome was a composite of clinically significant shoulder dystocia, fracture of the clavicle, brachial plexus injury, intracranial haemorrhage, or death. We did analyses by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00190320. We randomly assigned 409 women to the induction group and 413 women to the expectant management group, of whom 407 women and 411 women, respectively, were included in the final analysis. Mean birthweight was 3831 g (SD 324) in the induction group and 4118 g (392) in the expectant group. Induction of labour significantly reduced the risk of shoulder dystocia or associated morbidity (n=8) compared with expectant management (n=25; relative risk [RR] 0·32, 95% CI 0·15-0·71; p=0·004). We recorded no brachial plexus injuries, intracranial haemorrhages, or perinatal deaths. The likelihood of spontaneous vaginal delivery was higher in women in the induction group than in those in the expectant management group (RR 1·14, 95% CI 1·01-1·29). Caesarean delivery and neonatal morbidity did not differ significantly between the groups. Induction of labour for suspected large-for-date fetuses is associated with a reduced risk of shoulder dystocia and associated morbidity compared with expectant management. Induction of labour does not increase the risk of caesarean delivery and improves the likelihood of spontaneous vaginal delivery. These benefits should be balanced with the effects of early-term induction of labour. Assistance Publique-Hôpitaux de Paris and the University of Geneva. Copyright © 2015 Elsevier Ltd. All rights reserved.
    The Lancet 04/2015; 385(9987). DOI:10.1016/S0140-6736(14)61904-8 · 45.22 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S386-S387. DOI:10.1016/j.ajog.2014.10.1004 · 4.70 Impact Factor
  • American Journal of Obstetrics and Gynecology 01/2015; 212(1):S376. DOI:10.1016/j.ajog.2014.10.983 · 4.70 Impact Factor
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    ABSTRACT: Objective To investigate missed opportunities for diagnosing female genital mutilation (FGM) at an obstetrics and gynecology (OB/GYN) department in Switzerland. Methods In a retrospective study, we included 129 consecutive women with FGM who attended the FGM outpatient clinic at the Department of Gynecology and Obstetrics at the University Hospitals of Geneva between 2010 and 2012. The medical files of all women who had undergone at least 1 previous gynecologic exam performed by an OB/GYN doctor or a midwife at the study institution were reviewed. The type of FGM reported in the files was considered correct if it corresponded to that reported by the specialized gynecologist at the FGM clinic, according to WHO classification. Results In 48 (37.2%) cases, FGM was not mentioned in the medical file. In 34 (26.4%) women, the diagnosis was correct. FGM was identified but erroneously classified in 28 (21.7%) cases. There were no factors (women’s characteristics or FGM type) associated with missed diagnosis. Conclusion Opportunities to identify FGM are frequently missed. Measures should be taken to improve FGM diagnosis and care.
    International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics 06/2014; 125(3). DOI:10.1016/j.ijgo.2013.11.016 · 1.54 Impact Factor
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    ABSTRACT: The occipito-posterior (OP) fetal head position during the first stage of labour occurs in 10-34% of cephalic presentations. Most will spontaneous rotate in anterior position before delivery, but 5-8% of all births will persist in OP position for the third stage of labour. Previous observations have shown that this can lead to an increase of complications, such as an abnormally long labour, maternal and fetal exhaustion, instrumental delivery, severe perineal tears, and emergency caesarean section. Usual care in the case of diagnosis of OP position is an expectant management. However, maternal postural techniques have been reported to promote the anterior position of the fetal head for delivery. A Cochrane review reported that these maternal positions are well accepted by women and reduce back pain. However, the low sample size of included studies did not allow concluding on their efficacy on delivery outcomes, particularly those related to persistent OP position. Our objective is to evaluate the efficacy of maternal position in the management of OP position during the first stage of labour.Methods/design: A randomised clinical trial is ongoing in the maternity unit of the Geneva University Hospitals, Geneva, Switzerland. The unit is the largest in Switzerland with 4,000 births/year. The trial will involve 438 women with a fetus in OP position, confirmed by sonography, during the first stage of the labour. The main outcome measure is the position of the fetal head, diagnosed by ultrasound one hour after randomisation. It is important to evaluate the efficacy of maternal position to correct fetal OP position during the first stage of the labour. Although these positions seem to be well accepted by women and appear easy to implement in the delivery room, the sample size of the last randomised clinical trial published in 2005 to evaluate this intervention had insufficient power to demonstrate clear evidence of effectiveness. If the technique demonstrates efficacy, it would reduce the physical and psychological consequences of complications at birth related to persistent OP position.Trial registration: ClinicalTrials.gov, www.clinicaltrials.gov: (no. NCT01291355).
    BMC Pregnancy and Childbirth 02/2014; 14(1):83. DOI:10.1186/1471-2393-14-83 · 2.19 Impact Factor
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    ABSTRACT: Tocolysis is an important treatment in the improvement of outcome in preterm labor and preterm birth, provided that its use follows clear evidence-based recommendations. In this expert opinion, the most recent evidence about efficacy and side effects of different tocolytics is being reviewed and evidence-based recommendation about diagnosis and treatment of preterm labor is given. Further aspects such as progesterone administration or antibiotic treatment for the prevention of preterm birth are included. Our review demonstrates that an individualized choice of different tocolytics and additional treatments is necessary to improve short- and long-term neonatal outcome in preterm labor and preterm birth.
    Archives of Gynecology 01/2014; 289(4). DOI:10.1007/s00404-013-3137-9 · 1.36 Impact Factor
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    Marie Cohen · Pascale Ribaux · Manuella Epiney · Olivier Irion
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    ABSTRACT: Glucose-regulated protein 78 (GRP78) is an endoplasmic reticulum (ER) molecular chaperone that belongs to the heat shock protein 70 family. GRP78 is also present on the cell surface membrane of trophoblastic cells, where it is associated with invasive or fusion properties of these cells. Impaired mechanism of GRP78 relocation from ER to the cell surface was observed in preeclamptic cytotrophoblastic cells (CTB) and could take part in the pathogenesis of preeclampsia. In this study, we have investigated whether prostate apoptosis response 4 (Par-4), a protein identified as a partner of GRP78 relocation to the cell surface in prostate cancer cells, is present in trophoblastic cells and is involved in the translocation of GRP78 to the cell surface of CTB. Par-4 is indeed present in trophoblastic cells and its expression correlates with expression of membrane GRP78. Moreover, overexpression of Par-4 led to an increase of cell surface expression of GRP78 and decreased Par-4 gene expression reduced cell surface localization of GRP78 confirming a role of Par-4 in relocation of GRP78 from ER to the cell surface. Accordingly, invasive property was modified in these cells. In conclusion, we show that Par-4 is expressed in trophoblastic cells and is involved in transport of GRP78 to the cell surface and thus regulates invasive property of extravillous CTB.
    PLoS ONE 11/2013; 8(11):e80231. DOI:10.1371/journal.pone.0080231 · 3.23 Impact Factor
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    ABSTRACT: Unintended pregnancies reflect an unmet need for family planning, and are part of health disparities. Using the only database to inquire about pregnancy intention among women in Switzerland, this study examined the relationship between immigrant documentation and unintended pregnancy (UP). Among pregnant women presenting to a Swiss hospital, we compared pregnancy intention between documented and undocumented women. We used logistic regression to examine whether undocumented status was associated with UP after adjusting for other significant predictors. Undocumented women had more unintended pregnancies (75.2 vs. 20.6 %, p = 0.00). Undocumented status was associated with UP after adjustment (OR 6.23, 95 % CI 1.83-21.2), as was a history of psychological problems (OR 4.09, 95 % CI 1.32-12.7). Contraception non-use was notably associated with lower odds of UP (OR 0.01, 95 % CI 0.004-0.04). Undocumented status was significantly associated with UP, even after adjusting for well-recognized risk factors. This highlights the tremendous risk of undocumented status on UP among women in Switzerland.
    Journal of Immigrant and Minority Health 11/2013; 17(2). DOI:10.1007/s10903-013-9939-9 · 1.16 Impact Factor
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    ABSTRACT: Obstetrical emergencies may represent extremely critical situations with potential dramatic maternal and neonatal consequences. These situations should be managed by an effective and experienced multidisciplinary staff. Simulation allows a regular and repeated practice of these situations with no risk to patient safety and the possibility to analyse participants' performances in a group. This review describes different obstetrical simulation methods and summarizes the evidence for its efficiency in obstetric practice.
    Revue médicale suisse 10/2013; 9(403):1938-40, 1942.
  • Lucia Floris · Olivier Irion
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    ABSTRACT: This study investigated the association between anxiety experienced by the mother, a request for analgesia, and the level of pain at maternity hospital admission in early labour. Anxiety levels were measured by the State-Trait Anxiety Inventory and pain was assessed using a Visual Analogue Scale. Anxiety and Visual Analogue Scale scores were compared using a linear regression model and indicated a statistically significant association between the anxiety state and degree of pain (p < 0.016; Y = 0.895 x score + 32.656). There was no significant association between anxiety and a request for epidural analgesia. During labour, an evaluation of anxiety should be associated with an assessment of the perceived degree of pain.
    Journal of Health Psychology 10/2013; 20(4). DOI:10.1177/1359105313502695 · 1.88 Impact Factor
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    ABSTRACT: Cardiovascular diseases are the principal cause of death in women in developed countries and are importantly promoted by hypertension. The salt sensitivity of blood pressure (BP) is considered as an important cardiovascular risk factor at any BP level. Preeclampsia is a hypertensive disorder of pregnancy that arises as a risk factor for cardiovascular diseases. This study measured the salt sensitivity of BP in women with a severe preeclampsia compared with women with no pregnancy hypertensive complications. Forty premenopausal women were recruited 10 years after delivery in a case-control study. Salt sensitivity was defined as an increase of >4 mm Hg in 24-hour ambulatory BP on a high-sodium diet. The ambulatory BP response to salt was significantly increased in women with a history of preeclampsia compared with that of controls. The mean (95% confidence interval) daytime systolic/diastolic BP increased significantly from 115 (109-118)/79 (76-82) mm Hg on low-salt diet to 123 (116-130)/80 (76-84) on a high-salt diet in women with preeclampsia, but not in the control group (from 111 [104-119]/77 [72-82] to 111 [106-116]/75 [72-79], respectively, P<0.05). The sodium sensitivity index (SSI=Δmean arterial pressure/Δurinary Na excretion×1000) was 51.2 (19.1-66.2) in women with preeclampsia and 6.6 (5.8-18.1) mm Hg/mol per day in controls (P=0.015). The nocturnal dip was blunted on a high-salt diet in women with preeclampsia. Our study shows that women who have developed preeclampsia are salt sensitive before their menopause, a finding that may contribute to their increased cardiovascular risk. Women with a history of severe preeclampsia should be targeted at an early stage for preventive measures of cardiovascular diseases.
    Hypertension 08/2013; 62(4). DOI:10.1161/HYPERTENSIONAHA.113.01916 · 6.48 Impact Factor
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    ABSTRACT: Obstetric work generates important subjective and objective mental stress and is perceived as a physically demanding activity by obstetricians. The aim of this study was to quantify physical and mental stress levels in obstetricians at work and during leisure activities to investigate their association with overall physical activity levels and professional experience. 18 obstetricians at the maternity unit of the University of Geneva Hospitals were enrolled in a prospective observational study. Physical activity and stress levels were measured in two different activity sectors (delivery room and outpatient clinic) and outside work. Physical activity was assessed by questionnaire, visual analogue scale (VAS), and accelerometer. Mental stress levels were assessed by validated questionnaires, VAS, measurement of urine catecholamines and salivary cortisol, and night-time heart rate variability indices. Daily stress levels were higher at work compared to outside work (all, P=0.002). Adrenalin (P=0.002) and dopamine (P=0.09) levels were elevated after a labour suite shift and a trend was observed for reduced heart rate variability during the night after this shift. The median average daily number of steps was 7132 (range, 5283-8649). Subjects reached a median of 32min (range, 19-49min) of moderate or higher intensity (≥1952counts/min) daily physical activity. Contrary to perception, obstetrics work is not physically demanding. It is, however, accompanied by important subjective and objective mental stress that may have a negative impact on health when combined with a lack of regular daily physical activity.
    European journal of obstetrics, gynecology, and reproductive biology 08/2013; 171(1). DOI:10.1016/j.ejogrb.2013.08.020 · 1.70 Impact Factor
  • American journal of obstetrics and gynecology 06/2013; 209(5). DOI:10.1016/j.ajog.2013.06.016 · 4.70 Impact Factor
  • Olivier Irion
    Circulation 03/2013; 127(9):e477. DOI:10.1161/CIRCULATIONAHA.112.112227 · 14.43 Impact Factor
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    ABSTRACT: Abstract Objective: To assess the effectiveness of hypnosis to reduce pain and facilitate external cephalic version (ECV). Design: Cohort study. Setting: Geneva University Hospitals, Switzerland. Participants: 63 women attempting ECV under hypnosis from 2010 to 2011 were compared with 122 women who received standard care from 2005 through 2008. Intervention: Immediately after the ECV attempt, both groups completed the same questionnaire evaluating the participants' pain (visual analogue and verbal rating scales) and experience with the procedure. Physicians also completed a questionnaire that elicited their views on the effect of hypnosis on the intervention. A chi-squared test was used to compare differences in proportions, and the Mann-Whitney U test was used for differences in continuous variables. A thematic content analysis of the obstetricians' responses to the open question regarding their experience of hypnotist accompaniment was also performed. Outcome Measures: Pain evaluated by women (visual analogue and verbal rating scales) and success rate of ECV. Results: Pain intensity reported by women did not significantly differ between the hypnosis group and the standard care group (visual analogue scale score, 6.0 versus 6.3, respectively; p=.25; difference for verbal rating scale, p=0.31. In 72% of cases, physicians reported that hypnosis facilitated the procedure. The success rates in both groups were not significantly different (30% with hypnosis compared with 38% without; p=.31). Most women in both groups found the ECV attempt painful and a source of anxiety but would undergo it again if necessary. Conclusion: Hypnosis accompaniment during ECV does not reduce pain intensity associated with the procedure or improve the probability of a successful version.
    Journal of alternative and complementary medicine (New York, N.Y.) 03/2013; 19(10). DOI:10.1089/acm.2012.0945 · 1.59 Impact Factor
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    ABSTRACT: This study determined whether anti-Müllerian hormone (AMH) concentration influences the time necessary to conceive a live-born child – effective time to pregnancy (eTTP) – in a population of women who conceived naturally. This is an observational study of 87 women with a planned spontaneous pregnancy resulting in a live birth. eTTP was assessed retrospectively by a questionnaire and AMH was measured in a frozen serum sample from first trimester of pregnancy. eTTP was correlated with age (r = −0.24, P = 0.02), but not with AMH (r = −0.10) or body mass index (r = 0.05). With logistic regressions, the only variable that affected the probability of pregnancy within 3 or 6 months was age, irrespective of whether an AMH concentration limit of 1.0 ng/ml or 2.0 ng/ml was chosen. In conclusion, this study suggests that there is no relationship between AMH concentration and eTTP and therefore speaks against determining AMH in women who are not infertile for the purpose of predicting their chances of pregnancy. The findings are concordant with previous reports describing AMH as a quantitative but not a qualitative marker of ovarian reserve and therefore does not reflect a woman’s ability to become pregnant. Anti-Müllerian hormone (AMH) is secreted by ovarian follicles and reflects a woman’s ovarian reserve – the number of small growing follicles at a given time. AMH concentrations has been extensively studied in infertile women but there are only scarce data on AMH in non-infertile women. Our objective was to determine whether AMH concentrations influence the time necessary to conceive a live-born child – also called effective time to pregnancy (eTTP) – in a population of women who conceived naturally. We conducted an observational study between 2007 and 2009 in which we assessed eTTP retrospectively in 87 women who had delivered a live-born child and measured AMH in a frozen blood sample collected during the first trimester of pregnancy. The results of our study show, as expected, a decrease of AMH concentrations as age increases but no relationship between AMH and eTTP. In conclusion, our study results suggest AMH concentrations do not influence the time necessary to conceive a live-born child spontaneously and therefore speak against determining AMH in women who are not infertile for the purpose of predicting their chances of pregnancy. Our findings are concordant with previous reports describing AMH as a quantitative but not a qualitative marker of ovarian function that does therefore not reflect a woman’s ability to become pregnant.
    Reproductive biomedicine online 01/2013; 28(2). DOI:10.1016/j.rbmo.2013.10.007 · 3.02 Impact Factor
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    ABSTRACT: Objectives: The aims of this study were to gain a better understanding of the motivations of pregnant women utilizing moxibustion for breech presentation and to measure the impact of research results on these patients' treatment decisions regarding this alternative medicine technique. Design: The study involved a statistical analysis of two self-administered questionnaires to 212 women who had previously participated in a randomized clinical trial on the efficacy of moxibustion; in addition, a qualitative thematic content analysis for open-ended questions was also performed. Results: Most women (69%) reported treating themselves at least once with complementary and alternative medicine (CAM). Higher use of CAM was associated with higher education and Caucasian origin. Pregnancy was associated with a significant reduction in utilization of CAMs. After reading the results of a previous randomized clinical trial, which did not demonstrate efficacy of moxibustion, 60% of the women questioned expressed the intention of resorting to this technique in case of a subsequent pregnancy with a fetus in the breech position. The principal motivation was their desire to try anything that may possibly turn such fetuses to increase the chances of delivering them vaginally. Conclusions: It is important to consider the regard that pregnant women attribute to CAMs for self-care strategies. Despite a lack of scientific evidence supporting the use of moxibustion to address breech presentation, pregnant women consider CAMs, in general, to be safe and effective. Studies investigating the physical and psychologic effects of CAMs will enable clinicians to advise patients better about treatment options.
    Journal of alternative and complementary medicine (New York, N.Y.) 10/2012; 18(12). DOI:10.1089/acm.2011.0550 · 1.59 Impact Factor
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    ABSTRACT: Objective: Oral iron substitution has shown to be insufficient for treatment of severe iron deficiency anemia in pregnancy. Ferric carboxymaltose is a new intravenous (i.v.) iron formulation promising to be more effective and as safe as iron sucrose. We aimed to assess side effects and tolerance of ferric carboxymaltose compared to i.v. iron sucrose in pregnant women. Methods: We performed a retrospective analysis of 206 pregnant women who were treated either with ferric carboxymaltose or iron sucrose for iron-deficiency anemia with intolerability to oral iron substitution, or insufficient hemoglobin increase after oral iron treatment, or need for rapid hemoglobin reconstitution. Primary endpoint was to evaluate the maternal safety and tolerability. Secondary endpoint was to assess efficacy of the treatment and exclude safety concerns for the fetus. Results: The incidence of drug-related adverse events was low and mostly mild in both groups. Mild adverse events occurred in 7.8% for ferric carboxymaltose and in 10.7% for iron sucrose. The mean rise of hemoglobin value was 15.4 g/L for ferric carboxymaltose and 11.7 g/L for iron sucrose. Conclusion: Ferric carboxymaltose administration in pregnant women is well tolerated and is not associated with any relevant clinical safety concerns. Ferric carboxymaltose has a comparable safety profile to iron sucrose but offers the advantage of a much higher iron dosage at a time reducing the need for repeated applications and increasing patients' comfort. Ferric carboxymaltose is the drug of choice, if i.v. iron treatment becomes necessary in the second or third trimester of pregnancy.
    Journal of Perinatal Medicine 09/2012; 40(5):469-74. DOI:10.1515/jpm-2011-0231 · 1.36 Impact Factor
  • Marie Cohen · Pascale Ribaux · Manuella Epiney · Olivier Irion
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    ABSTRACT: Preeclampsia is a specific pregnancy disorder which could be due, at least in part, to impaired invasion of trophoblastic cells. Since matrix metalloproteinases (MMPs) are the predominant proteases involved in trophoblastic invasion, we investigated and compared expression of MMP-1, 2, 7, 9 and 12 of cytotrophoblastic cells (CTB) purified from preeclamptic (PE) placentas to control CTB. In order to evaluate invasive properties of cells, purified CTB were seeded on collagen-coated insert following boyden chamber principle and matrix metalloproteinases (MMPs) expression was evaluated by qPCR. Our results showed that PE CTB are less invasive than control CTB in vitro. In parallel, expression of MMPs, except for MMP-2, tends to be decreased in PE CTB compared to control CTB. At the exception of MMP-2, this study confirms the importance of MMPs in development of PE.
    Neuro endocrinology letters 08/2012; 33(4):406-11. · 0.80 Impact Factor
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    ABSTRACT: Glucose-regulated protein 78 (GRP78) is highly expressed in first trimester cytrophoblastic cells (CTBs), especially in syncytiotrophoblast (STB). However, the role of GRP78 in these cells has never been investigated. In this study, we have examined the role of GRP78 in trophoblast fusion using the Bewo choriocarcinoma cell line as a model of cytotrophoblast fusion. Down regulation of GRP78 by siRNA or chemical inhibitors and use of antibodies against GRP78 in culture medium significantly decreased forskolin-induced fusion capacity of Bewo cells suggesting the involvement of membrane GRP78 in trophoblast fusion. GRP78 expression was also studied in preeclamptic (PE) CTBs which are known to have lower fusion capacity compared to control CTBs. Interestingly, despite the increase of GRP78 mRNA in PE CTBs, membrane GRP78 is significantly decreased in PE CTBs compared to control CTBs, suggesting that relocation of GRP78 from the endoplasmic reticulum to cell surface is probably altered in PE CTBs. Our results imply that membrane GRP78 could play an important role in syncytialisation. They also suggest that deregulation of GRP78 expression or relocation at cell surface might be involved in pregnancy complication associated with defective syncytialisation, such as preeclampsia.
    PLoS ONE 08/2012; 7(8):e40596. DOI:10.1371/journal.pone.0040596 · 3.23 Impact Factor

Publication Stats

2k Citations
346.75 Total Impact Points


  • 1998–2015
    • University of Geneva
      • • Department of Obstetrics and Gynaecology
      • • Division of Obstetrics
      Genève, Geneva, Switzerland
    • Centre Hospitalier Universitaire de Québec (CHUQ)
      Québec, Quebec, Canada
  • 2014
    • Inselspital, Universitätsspital Bern
      • Department of Obstetrics and Gynaecology
      Berna, Bern, Switzerland
  • 1998–2011
    • Hôpitaux Universitaires de Genève
      • • Département de gynécologie et d'obstétrique
      • • Unité de développement en obstétrique
      Genève, Geneva, Switzerland
  • 1996
    • Université du Québec
      Québec, Quebec, Canada