The BISTIM study: a randomized controlled trial comparing dual ovarian stimulation (duostim) with two conventional ovarian stimulations in poor ovarian responders undergoing IVF.

STUDY QUESTION: Is the total number of oocytes retrieved with dual ovarian stimulation in the same cycle (duostim) higher than with two consecutive antagonist cycles in poor responders? SUMMARY ANSWER: Based on the number of total and mature oocytes retrieved in women with poor ovarian response (POR), there is no benefit of duostim versus two consecutive antagonist cycles. WHAT IS KNOWN ALREADY: Recent studies have shown the ability to obtain oocytes with equivalent quality from the follicular and the luteal phase, and a higher number of oocytes within one cycle when using duostim. If during follicular stimulation smaller follicles are sensitized and recruited, this may increase the number of follicles selected in the consecutive luteal phase stimulation, as shown in non-randomized controlled trials (RCT). This could be particularly relevant for women with POR. STUDY DESIGN, SIZE, DURATION: This is a multicentre, open-labelled RCT, performed in four IVF centres from September 2018 to March 2021. The primary outcome was the number of oocytes retrieved over the two cycles. The primary objective was to demonstrate in women with POR that two ovarian stimulations within the same cycle (first in the follicular phase, followed by a second in the luteal phase) led to the retrieval of 1.5 (2) more oocytes than the cumulative number of oocytes from two consecutive conventional stimulations with an antagonist protocol. In a superiority hypothesis, with power 0.8 alpha-risk 0.05 and a 35% cancellation rate, 44 patients were needed in each group. Patients were randomized by computer allocation. PARTICIPANTS/MATERIALS, SETTING, METHODS: Eighty-eight women with POR, defined using adjusted Bologna criteria (antral follicle count ≤5 and/or anti-Müllerian hormone ≤1.2 ng/ml) were randomized, 44 in the duostim group and 44 in the conventional (control) group. HMG 300 IU/day with flexible antagonist protocol was used for ovarian stimulation, except in luteal phase stimulation of the duostim group. In the duostim group, oocytes were pooled and inseminated after the second retrieval, with a freeze-all protocol. Fresh transfers were performed in the control group, frozen embryo transfers were performed in both control and duostim groups in natural cycles. Data underwent intention-to-treat and per-protocol analyses. MAIN RESULTS AND THE ROLE OF CHANCE: There was no difference between the groups regarding demographics, ovarian reserve markers, and stimulation parameters. The mean (SD) cumulative number of oocytes retrieved from two ovarian stimulations was not statistically different between the control and duostim groups, respectively, 4.6 (3.4) and 5.0 (3.4) [mean difference (MD) [95% CI] +0.4 [-1.1; 1.9], P = 0.56]. The mean cumulative numbersof mature oocytes and total embryos obtained were not significantly different between groups. The total number of embryos transferred by patient was significantly higher in the control group 1.5 (1.1) versus the duostim group 0.9 (1.1) (P = 0.03). After two cumulative cycles, 78% of women in the control group and 53.8% in the duostim group had at least one embryo transfer (P = 0.02). There was no statistical difference in the mean number of total and mature oocytes retrieved per cycle comparing Cycle 1 versus Cycle 2, both in control and duostim groups. The time to the second oocyte retrieval was significantly longer in controls, at 2.8 (1.3) months compared to 0.3 (0.5) months in the duostim group (P < 0.001). The implantation rate was similar between groups. The cumulative live birth rate was not statistically different, comparing controls versus the duostim group, 34.1% versus 17.9%, respectively (P = 0.08). The time to transfer resulting in an ongoing pregnancy did not differ in controls 1.7 (1.5) months versus the duostim group, 3.0 (1.6) (P = 0.08). No serious adverse events were reported. LIMITATIONS, REASONS FOR CAUTION: The RCT was impacted by the coronavirus disease 2019 pandemic and the halt in IVF activities for 10 weeks. Delays were recalculated to exclude this period; however, one woman in the duostim group could not have the luteal stimulation. We also faced unexpected good ovarian responses and pregnancies after the first oocyte retrieval in both groups, with a higher incidence in the control group. However, our hypothesis was based on 1.5 more oocytes in the luteal than the follicular phase in the duostim group, and the number of patients to treat was reached in this group (N = 28). This study was only powered for cumulative number of oocytes retrieved. WIDER IMPLICATIONS OF THE FINDINGS: This is the first RCT comparing the outcome of two consecutive cycles, either in the same menstrual cycle or in two consecutive menstrual cycles. In routine practice, the benefit of duostim in patients with POR regarding fresh embryo transfer is not confirmed in this RCT: first, because this study demonstrates no improvement in the number of oocytes retrieved in the luteal phase after follicular phase stimulation, in contrast to previous non-randomized studies, and second, because the freeze-all strategy avoids a pregnancy with fresh embryo transfer after the first cycle. However, duostim appears to be safe for women. In duostim, the two consecutive processes of freezing/thawing are mandatory and increase the risk of wastage of oocytes/embryos. The only benefit of duostim is to shorten the time to a second retrieval by 2 weeks if accumulation of oocytes/embryos is needed. STUDY FUNDING/COMPETING INTERESTS: This is an investigator-initiated study supported by a research Grant from IBSA Pharma. N.M. declares grants paid to their institution from MSD (Organon France); consulting fees from MSD (Organon France), Ferring, and Merck KGaA; honoraria from Merck KGaA, General Electrics, Genevrier (IBSA Pharma), and Theramex; support for travel and meetings from Theramex, Merck KGaG, and Gedeon Richter; and equipment paid to their institution from Goodlife Pharma. I.A. declares honoraria from GISKIT and support for travel and meetings from GISKIT. G.P.-B. declares Consulting fees from Ferring and Merck KGaA; honoraria from Theramex, Gedeon Richter, and Ferring; payment for expert testimony from Ferring, Merck KGaA, and Gedeon Richter; and support for travel and meetings from Ferring, Theramex, and Gedeon Richter. N.C. declares grants from IBSA pharma, Merck KGaA, Ferring, and Gedeon Richter; support for travel and meetings from IBSA pharma, Merck KGaG, MSD (Organon France), Gedeon Richter, and Theramex; and participation on advisory board from Merck KGaA. E.D. declares support for travel and meetings from IBSA pharma, Merck KGaG, MSD (Organon France), Ferring, Gedeon Richter, Theramex, and General Electrics. C.P.-V. declares support for travel and meetings from IBSA Pharma, Merck KGaA, Ferring, Gedeon Richter, and Theramex. M.Pi. declares support for travel and meetings from Ferring, Gedeon Richetr, and Merck KGaA. M.Pa. declares honoraria from Merck KGaA, Theramex, and Gedeon Richter; support for travel and meetings from Merck KGaA, IBSA Pharma, Theramex, Ferring, Gedeon Richter, and MSD (Organon France). H.B.-G. declares honoraria from Merck KGaA, and Gedeon Richter and support for travel and meetings from Ferring, Merck KGaA, IBSA Pharma, MSD (Organon France), Theramex, and Gedeon Richter. S.G. and M.B. have nothing to declare. TRIAL REGISTRATION NUMBER: Registration number EudraCT: 2017-003223-30. ClinicalTrials.gov identifier: NCT03803228. TRIAL REGISTRATION DATE: EudraCT: 28 July 2017. ClinicalTrials.gov: 14 January 2019. DATE OF FIRST PATIENT'S ENROLMENT: 3 September 2018.

A large observational data study supporting the PROsPeR score classification in poor ovarian responders according to live birth outcome.

STUDY QUESTION: Can the Poor Responder Outcome Prediction (PROsPeR) score identify live birth outcomes in subpopulations of patients with poor ovarian response (POR) defined according to the ESHRE Bologna criteria (female age, anti-Müllerian hormone (AMH), number of oocytes retrieved during the previous cycle (PNO) after treatment with originator recombinant human follitropin alfa? SUMMARY ANSWER: The PROsPeR score discriminated the probability of live birth in patients with POR using observational data with fair discrimination (AUC ≅ 70%) and calibration, and the AUC losing less than 5% precision compared with a model developed using the observational data. WHAT IS KNOWN ALREADY: Although scoring systems for the likelihood of live birth after ART have been developed, their accuracy may be insufficient, as they have generally been developed in the general population with infertility and were not validated for patients with POR. The PROsPeR score was developed using data from the follitropin alfa (GONAL-f; Merck KGaA, Darmstadt, Germany) arm of the Efficacy and Safety of Pergoveris in Assisted Reproductive Technology (ESPART) randomized controlled trial (RCT) and classifies women with POR as mild, moderate or severe, based upon three variables: female age, serum AMH level and number of oocytes retrieved during the previous cycle (PNO). STUDY DESIGN, SIZE, DURATION: The external validation of the PROsPeR score was completed using data derived from eight different centres in France. In addition, the follitropin alfa data from the ESPART RCT, originally used to develop the PROsPeR score, were used as reference cohort. The external validation of the PROsPeR score l was assessed using AUC. A predetermined non-inferiority limit of 0.10 compared with a reference sample and calibration (Hosmer-Lemeshow test) were the two conditions required for evaluation. PARTICIPANTS/MATERIALS, SETTING, METHODS: The observational cohort included data from 8085 ART treatment cycles performed with follitropin alfa in patients with POR defined according to the ESHRE Bologna criteria (17.6% of the initial data set). The ESPART cohort included 477 ART treatment cycles with ovarian stimulation performed with follitropin alfa in patients with POR. MAIN RESULTS AND THE ROLE OF CHANCE: The external validation of the PROsPeR score to identify subpopulations of women with POR with different live birth outcomes was shown in the observational cohort (AUC = 0.688; 95% CI: 0.662, 0.714) compared with the ESPART cohort (AUC = 0.695; 95% CI: 0.623, 0.767). The AUC difference was -0.0074 (95% CI: -0.083, 0.0689). This provided evidence, with 97.5% one-sided confidence, that there was a maximum estimated loss of 8.4% in discrimination between the observational cohort and the ESPART cohort, which was below the predetermined margin of 10%. The Hosmer-Lemeshow test did not reject the calibration when comparing observed and predicted data (Hosmer-Lemeshow test = 1.266688; P = 0.260). LIMITATIONS, REASONS FOR CAUTION: The study was based on secondary use of data that had not been collected specifically for the analysis reported here and the number of characteristics used to classify women with POR was limited to the available data. The data were from a limited number of ART centres in a single country, which may present a bias risk; however, baseline patient data were similar to other POR studies. WIDER IMPLICATIONS OF THE FINDINGS: This evaluation of the PROsPeR score using observational data supports the notion that the likelihood of live birth may be calculated with reasonable precision using three readily available pieces of data (female age, serum AMH and PNO). The PROsPeR score has potential to be used to discriminate expected probability of live birth according to the degree of POR (mild, moderate, severe) after treatment with follitropin alfa, enabling comparison of performance at one centre over time and the comparison between centres. STUDY FUNDING/COMPETING INTEREST(S): This analysis was funded by Merck KGaA, Darmstadt, Germany. P.L. received grants from Merck KGaA, outside of the submitted work. N.M. reports grants, personal fees and non-financial support from Merck KGaA outside the submitted work. T.D.H. is Vice President and Head of Global Medical Affairs Fertility, Research and Development at Merck KGaA, Darmstadt, Germany. P.A. has received personal fees from Merck KGaA, Darmstadt, Germany, outside the submitted work. C.R. has received grants and personal fees from Gedeon Richter and Merck Serono S.A.S., France, an affiliate of Merck KGaA, Darmstadt, Germany, outside the submitted work. P.S. reports congress support from Merck Serono S.A.S., France (an affiliate of Merck KGaA, Darmstadt, Germany), Gedeon Richter, TEVA and MDS outside the submitted work. C.A., J.P., G.P. and R.W. declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

[Dydrogesterone versus micronized vaginal progesterone as luteal phase support after fresh embryo transfer in IVF]. / Dydrogestérone vs progestérone vaginale micronisée dans le soutien de la phase lutéale après transfert frais d'embryons.

OBJECTIVES: The objective of the study was to compare the live birth rate and miscarriage rate after fresh embryo transfer (Fresh ET) when patients are treated either with oral dydrogesterone or micronized vaginal progesterone (MVP) as luteal phase support (LPS). The vaginal route is still preferred, despite the discomfort for the patients and recent RCTs showing similar results for dydrogesterone and MVP. METHODS: All 556 consecutive Fresh ET after autologous IVF procedure, from December 2011 to March 2013 in one centre in France were included. Patients were treated either with dydrogesterone 10mg every 12hours (n=267) or MVP 200mg every 12hours (n=289), the physician's arbitrary choice on the day of the oocyte aspiration procedure. RESULTS: The groups were comparable regarding the demographic data and stimulation protocols, except for the rank of the oocyte pickup procedure [1.54±0.80 vs. 1.74±0.96, (P=0.01)], with no significant difference in live birth rates (22.4% vs. 23.8%, P=0.77) and miscarriage rates (4.1% vs. 5.5%, P=0.55) for dydrogesterone vs. MVP respectively. The results were similar in a good prognosis patients' subgroup. CONCLUSIONS: LPS with either dydrogesterone or MVP after Fresh ET showed similar live birth rates and miscarriage rates. The benefits of the oral over vaginal route might be higher tolerance and possibly better compliance. Dydrogesterone seems to be a safe treatment, but its long-term innocuity needs to be further proven.

Impact of endometrial preparation on early pregnancy loss and live birth rate after frozen embryo transfer: a large multicenter cohort study (14 421 frozen cycles).

STUDY QUESTION: Does the endometrial preparation protocol (artificial cycle (AC) vs natural cycle (NC) vs stimulated cycle (SC)) impact the risk of early pregnancy loss and live birth rate after frozen/thawed embryo transfer (FET)? SUMMARY ANSWER: In FET, ACs were significantly associated with a higher pregnancy loss rate and a lower live birth rate compared with SC or NC. WHAT IS KNOWN ALREADY: To date, there is no consensus on the optimal endometrial preparation in terms of outcomes. Although some studies have reported a higher pregnancy loss rate using AC compared with NC or SC, no significant difference was found concerning the pregnancy rate or live birth rate. Furthermore, no study has compared the three protocols in a large population. STUDY DESIGN SIZE DURATION: A multicenter retrospective cohort study was conducted in nine reproductive health units in France using the same software to record medical files between 1 January 2012 and 31 December 2016. FET using endometrial preparation by AC, modified NC or SC were included. The primary outcome was the pregnancy loss rate at 10 weeks of gestation. The sample size required was calculated to detect an increase of 5% in the pregnancy loss rate (21-26%), with an alpha risk of 0.5 and a power of 0.8. We calculated that 1126 pregnancies were needed in each group, i.e. 3378 in total. PARTICIPANTS/MATERIALS SETTING METHODS: Data were collected by automatic extraction using the same protocol. All consecutive autologous FET cycles were included: 14 421 cycles (AC: n = 8139; NC: n = 3126; SC: n = 3156) corresponding to 3844 pregnancies (hCG > 100 IU/l) (AC: n = 2214; NC: n = 812; SC: n = 818). Each center completed an online questionnaire describing its routine practice for FET, particularly the reason for choosing one protocol over another. MAIN RESULTS AND THE ROLE OF CHANCE: AC represented 56.5% of FET cycles. Mean age of women was 33.5 (SD ± 4.3) years. The mean number of embryos transferred was 1.5 (±0.5). Groups were comparable, except for history of ovulation disorders (P = 0.01) and prior delivery (P = 0.03), which were significantly higher with AC. Overall, the early pregnancy loss rate was 31.5% (AC: 36.5%; NC: 25.6%; SC: 23.6%). Univariable analysis showed a significant association between early pregnancy loss rate and age >38 years, history of early pregnancy loss, ovulation disorders and duration of cryopreservation >6 months. After adjustment (multivariable regression), the early pregnancy loss rate remained significantly higher in AC vs NC (odds ratio (OR) 1.63 (95% CI) [1.35-1.97]; P < 0.0001) and in AC vs SC (OR 1.87 [1.55-2.26]; P < 0.0001). The biochemical pregnancy rate (hCG > 10 and lower than 100 IU/l) was comparable between the three protocols: 10.7% per transfer. LIMITATIONS REASONS FOR CAUTION: This study is limited by its retrospective design that generates missing data. Routine practice within centers was heterogeneous. However, luteal phase support and timing of embryo transfer were similar in AC. Univariable analysis showed no difference between centers. Moreover, a large number of parameters were included in the analysis. WIDER IMPLICATIONS OF THE FINDINGS: Our study shows a significant increase in early pregnancy loss when using AC for endometrial preparation before FET. These results suggest either a larger use of NC or SC, or an improvement of AC by individualizing hormone replacement therapy for patients in order to avoid an excess of pregnancy losses. STUDY FUNDING/COMPETING INTERESTS: The authors declare no conflicts of interest in relation to this work. G.P.-B. declares consulting fees from Ferring, Gedeon-Richter, Merck KGaA, Theramex, Teva; Speaker's fees or equivalent from Merck KGaA, Ferring, Gedeon-Richter, Theramex, Teva. N.C. declares consulting fees from Ferring, Merck KGaA, Theramex, Teva; Speaker's fees or equivalent from Merck KGaA, Ferring. C.R. declares a research grant from Ferring, Gedeon-Richter; consulting fees from Gedeon-Richter, Merck KGaA; Speaker's fees or equivalent from Merck KGaA, Ferring, Gedeon-Richter; E.M.d'A. declares Speaker's fees or equivalent from Merck KGaA, MSD, Ferring, Gedeon-Richter, Theramex, Teva. I.C-D. declares Speaker's fees or equivalent from Merck KGaA, MSD, Ferring, Gedeon-Richter, IBSA. N.M. declares a research grant from Merck KGaA, MSD, IBSA; consulting fees from MSD, Ferring, Gedeon-Richter, Merck KGaA; Speaker's fees or equivalent from Merck KGaA, MSD, Ferring, Gedeon-Richter, Teva, Goodlife, General Electrics. TRIAL REGISTRATION NUMBER: N/A.

Random antral follicle count performed on any day of the menstrual cycle has the same predictive value as AMH for good ovarian response in IVF cycles.

OBJECTIVE: To determine whether the predictive value of AFC for ovarian response to stimulation for IVF depends on the day of the menstrual cycle when ultrasound is performed. METHODS: 410 women undergoing their first IVF cycle were included. All the women had AFC performed twice. The first measurement, random AFC (r-AFC), was performed during the fertility workup whatever the day of their menstrual cycle. Three groups were constituted according to the period of ultrasound performance: at early follicular phase i.e., day 1 to day 6 (eFP-AFC); at mid follicular phase i.e., day 7 to 12 (mFP-AFC) and at luteal phase i.e., day 13 or after (LP-AFC). A second AFC measurement was performed before the start of the ovarian stimulation (SD1-AFC). AMH dosing was done in the early follicular phase. RESULTS: Random AFC (r-AFC) was correlated to AMH (r = 0.69; p<0.001), SD1-AFC (r = 0.75; p<0.001) and number of oocytes retrieved (r = 0.49; p<0.001). When regarding AFC depending on the cycle day group, the correlation with AMH was 0.65, 0.66 and 0.85 for the eFP-AFC, the mFP-AFC and the LP-AFC respectively (all p were <0.001). The ROC analysis showed the same predictive value for good ovarian response (more than 6 oocytes retrieved) for the eFP-AFC, mFP-AFC and LP-AFC (AUC 0.73, 0.75 and 0.84 respectively; p = 0.28). The AUC of r-AFC (0.76) were similar to those of AMH (0.74) and SD1-AFC (0.74) (p = 0.21 and 0.92 respectively). CONCLUSION: AFC is strongly correlated with AMH and highly predictive of good ovarian response during the whole menstrual cycle.

Under-estimation of self-reported occupational exposure by questionnaire in hospital workers.

OBJECTIVES: The aim of the study was to determine whether self-reported occupational exposure to cleaning/disinfecting agents in hospital workers is accurate, in comparison to expert assessment, taken to be the gold standard. METHODS: In the Epidemiological Study of the Genetics and Environment of Asthma (EGEA), participants were interviewed on occupation with a specific questionnaire for hospital workers regarding tasks and cleaning/disinfecting agents. Two estimates of exposure were available: self-report and expert assessment. The expert assessment involved a standardised procedure to estimate intensity, frequency and probability of exposure for each job. The present analysis focused on eight exposures: formaldehyde, glutaraldehyde, bleach/chlorine, alcohol, quaternary ammonium components, ammonia, sprays and latex gloves. Agreement and differences between self-reported and expert estimates were studied by kappa and phi coefficients and McNemar tests, respectively. RESULTS: In the survey of 1571 adults, 176 ever hospital workers (327 occupations) with both self-reported and expert exposure assessments were studied. An underestimation of self-reported exposure was observed especially for formaldehyde (26.5% vs 32.7%, p=0.01), ammonia (7.4% vs 18.8%, p<0.0001), alcohol (64.9% vs 93.0%, p<0.0001) and quaternary ammonium components (16.6% vs 70.9%, p<0.0001), compared to expert assessment. CONCLUSION: Occupational exposure to disinfecting/cleaning agents is common and high in hospitals. A large underestimation of self-reported exposure and a lack of knowledge of product components was observed. Our results show the relevance of expert assessment in epidemiological studies to limit measurement bias. This work underlines the need for health education programmes on the occupational risks induced by these types of products.

Evaluation of different markers of the ovarian reserve in patients presenting with premature ovarian failure.

Premature ovarian failure (POF) is a heterogeneous syndrome, possibly due to mutations of genes involved in the normal development of the ovary and/or the follicles. Based essentially on animal models, these mutations are associated with various ovarian histological phenotypes, from a complete absence of to a partial follicular maturation. The aims of our work were in one hand to determine if ovarian histology, compared to pelvic ultrasonography, would be helpful either in identifying which patients display an impaired follicular growth or in the orientation of the POF etiology; on the other hand, since developing follicles up to the antral stage are reported in POF and that Anti-Müllerian hormone (AMH) might be a good indicator of follicular presence, we decided to determine whether AMH should be a better marker to determine the presence of an ovarian reserve in POF patients. To try to answer to the first question, we studied first 166 patients suffering from POF with a normal karyotype. Vaginal ultrasonography (US) was performed in 134 patients and an ovarian biopsy was obtained in 67 women. The presence of follicles suggested at US was confirmed at histology in only 56% of the patients. Ovarian histology led to the distinction of two phenotypes (a) small-sized ovaries, deprived of follicles, and (b) normal-sized ovaries with partial follicular maturation. To confirm the value of ovarian biopsies, samples from 20 normal women have been studied, confirming that ovarian biopsy at random allow reliable assessment of follicular activity. To try to answer to the second question of our work, a cross sectional study analyzing serum AMH, ovarian histology and AMH immunoexpression in 48 POF patients, was performed. Serum AMH was significantly higher in women with more than 5 follicles at ovarian histology. Ovarian AMH immunostaining revealed a normal AMH expression in POF preantral follicles but a decrease expression at the early antral stages. In conclusion, ovarian histology appears to be a reliable tool to appreciate the follicular reserve, and helpful and complementary to clinical and hormonal phenotyping in order to orient the search for various genetic causes of POF syndrome. Finally, AMH levels in POF patients could identify women with persistent follicles.

Respiratory symptoms and bronchial responsiveness among cleaning and disinfecting workers in the food industry.

OBJECTIVES: To measure the levels of exposure to nitrogen trichloride (NCl3) and aldehydes among cleaning and disinfecting workers in the atmosphere of food industry plants during cleaning and disinfecting operations, and to examine how they relate to irritant and chronic respiratory symptoms-which are indices of pulmonary function-and bronchial hyperresponsiveness (BHR) to methacholine. METHODS: 175 exposed workers (M = 149; F = 26) recruited from 17 enterprises of the food industry (8 cattle, pig, and ovine slaughterhouses, 8 fowl slaughterhouses, and 1 catering firm) and 70 non-exposed workers (M = 52; F = 18) were examined. Concentration levels of NCl3 and aldhehydes were measured by personal sampling. Symptoms were assessed by means of a questionnaire and the methacholine bronchial challenge (MBC) test using an abbreviated method. Subjects were labelled MBC+ if forced expiratory volume in one second (FEV1) fell by 20% or more. The linear dose-response slope (DRS) was calculated as the percentage fall in FEV1 at last dose divided by the total dose administered. RESULTS: 277 air samples were taken in the 17 food industry plants. For a given plant and in a given workshop, the actual concentrations of chloramines, aldehydes, and quaternary ammonium compounds were measured with personal samplers during the different steps of the procedures. For each cleaner, a total exposure index Sigma was calculated. A statistically significant concentration-response relationship was found between eye, nasal, and throat symptoms of irritation--but not chronic respiratory symptoms--and exposure levels or exposure duration. No relation was found between BHR and exposure. CONCLUSIONS: These data show that cleaning and disinfecting workers in the food industry are at risk of developing eye, nasal, and throat irritation symptoms. Although NCl3 exposure does not seem to carry a risk of developing permanent BHR, the possibility of transient BHR cannot be ruled out entirely.

Mortality among Paris sewage workers.

OBJECTIVES: To describe the mortality of Paris sewage workers. METHODS: A cohort of all Paris sewage workers since 1970 was established and followed up in mortality until 1999. The causes of death were determined by matching with a national database. The mortality rates were compared to the rates of a local reference population. RESULTS: A large excess in mortality (standardised mortality ratio (SMR) = 1.25; 530 cases, 95% CI 1.15 to 1.36) and in particular mortality from cancer (SMR = 1.37, 235 cases) was detected which was particularly important in the subgroup of subjects who had left employment because they resigned or were laid off (SMR = 1.77; 50 cases). The excess mortality is to a large extent due to alcohol related diseases (SMR = 1.65, 122 cases) especially malignant (SMR = 1.85, 16 cases) and non-malignant (SMR = 1.68, 38 cases) liver diseases, lung cancer (SMR = 1.47, 68 cases), and infectious diseases (SMR = 1.86, 25 cases). The SMRs for some diseases (all cancers, cancers of the oesophagus and lung, all alcohol related diseases) seem to increase with duration of employment as a sewage worker. Other than lung cancer, smoking related diseases were not in excess. CONCLUSION: The increased mortality by both malignant and non-malignant liver diseases is probably due to excessive alcohol consumption, but could be partially the result of occupational exposure to chemical and infectious agents and interactions of these factors. The excess lung cancer is unlikely to be due to an increased smoking prevalence.

Overexpression of copper zinc superoxide dismutase impairs human trophoblast cell fusion and differentiation.

The syncytiotrophoblast is the major component of the human placenta, involved in feto-maternal exchanges and secretion of pregnancy-specific hormones. Multinucleated syncytiotrophoblast arises from fusion of mononuclear cytotrophoblast cells. In trisomy 21-affected placentas, we recently have shown that there is a defect in syncytiotrophoblast formation and a decrease in the production of pregnancy-specific hormones. Due to the role of oxygen free radicals in trophoblast cell differentiation, we investigated the role of the key antioxidant enzyme, copper/zinc superoxide dismutase, encoded by chromosome 21 in in vitro trophoblast differentiation. We first observed that overexpression of superoxide dismutase in normal cytotrophoblasts impaired syncytiotrophoblast formation. This was associated with a significant decrease in mRNA transcript levels and secretion of hCG and other hormonal markers of syncytiotrophoblast. We confirmed abnormal cell fusion by overexpression of green fluorescence protein-tagged superoxide dismutase in cytotrophoblasts. In addition, a significant decrease in syncytin transcript levels was observed in superoxide dismutase-transfected cells. We then examined superoxide dismutase expression and activity in isolated trophoblast cells from trisomy 21-affected placentas. Superoxide dismutase mRNA expression (P < 0.05), protein levels (P < 0.01), and activity (P < 0.05) were significantly higher in trophoblast cells isolated from trisomy 21-affected placentas than in those from normal placentas. These results suggest that superoxide dismutase overexpression may directly impair trophoblast cell differentiation and fusion, and superoxide dismutase overexpression in Down's syndrome may be responsible at least in part for the failure of syncytiotrophoblast formation observed in trisomy 21-affected placentas.

Defect of syncytiotrophoblast formation and human chorionic gonadotropin expression in Down's syndrome.

The syncytiotrophoblast (ST) is a major component of the human placenta as it is involved in feto-maternal exchanges and the secretion of pregnancy-specific hormones. We have studied the formation and function of the ST in normal and trisomy 21 (T21)-affected placenta using the in vitro model of cytotrophoblast differentiation into ST. Cytotrophoblast cells were isolated from first trimester, second trimester and term placentae. In vitro cytotrophoblast cells isolated from normal placenta fused to form the ST. This was associated with an increase in the transcript levels and the secretion of human chorionic gonadotropin (hCG). However, the secretion of hCG decreased through pregnancy. In T21-affected placentae, we observed a defect (or a delay) in ST formation and a dramatic decrease in the synthesis and secretion of this hormone compared with cultured cells isolated from control age-matched placentae. These results were confirmed by a significant (P < 0.05) decrease in transcript levels of alpha and beta subunits of hCG in total homogenates of T21-affected placentae compared with controls. These results suggest a decrease in functional mass of ST in T21 placenta, and therefore a decrease in production of placental pregnancy-specific polypeptide hormones.

Mortality of aluminium reduction plant workers in France.

The mortality between 1950 and 1976 of 6455 French aluminium plant workers was analysed in order to assess occupational risks (especially lung cancer) associated with electrolysis, particularly with the Söderberg process. Mortality from all causes (SMR = 0.85), was lower in this cohort than in the French male population ('healthy worker effect'), and cancer mortality (SMR = 1.09) was only slightly higher. There was an excess of mortality from accidents (mainly non-occupational) in electrolysis workers (SMR = 1.38) and from cirrhosis of the liver in maintenance workers (SMR = 1.63). Among electrolysis workers, only those who had worked less than 10 years had a relative excess mortality from lung cancer (SMR = 1.94), but this did not seem to be associated with a particular electrolysis process. However a substantial underlying risk of lung cancer in Söderberg workers could not be excluded, although such a risk appeared unlikely for prebake workers.

Tracheal wheezes during methacholine airway challenge (MAC) in workers exposed to occupational hazards.

Methacholine airway challenge (MAC) is a simple and useful means to assess bronchial hyperreactivity in workers exposed to various occupational hazards. Recently, wheeze detection by tracheal auscultation has been proposed as an indicator of bronchial responsiveness during bronchial provocation test in children. Our aim was to examine the relationship between the appearance of wheezes and the concurrent changes in forced expiratory volume in one second (FEV1) observed during MAC test in adults. Three cumulative doses of a methacholine solution (100 micrograms, 500 micrograms and 1500 micrograms) were inhaled by 45 workers with occupational exposure to flour dust. Spirometry was done using an electronic spirometer. Tracheal sounds were recorded with an electronic stethoscope placed over the anterior cervical triangle, 2 cm above the sternal notch. The amplified sounds were stored on magnetic tape, band-pass filtered (50-2000 Hz), and digitized at a sampling rate of 4096 Hz into a GenRad Vibration Control System. Wheezes were detected by fast Fourier transform (FFT) analysis and their presence compared to a 20% fall in FEV1. A positive MAC test by spirometry was found in 12 subjects whereas wheezes were identified in 14 subjects. Among the wheezing subjects, nine had a positive MAC test (range of fall in FEV1 = 20.6 to 42.3%) and five had a negative one (range of fall in FEV1 = 3.6 to 16.9%). Moreover, no wheezes were found in the remaining three subjects with a positive MAC test (range of fall in FEV1 = 20.7 to 27.4%). Taking a 20% fall in FEV1 as reference, wheezes were 75% sensitive and 84.8% specific to detect airflow obstruction. In conclusion, since it carries a significant although small false-negative rate, the acoustic technique based upon wheeze detection cannot, at the present time, fully replace spirometry during airway challenge testing in subjects with suspected asthma.

[Normal coronary angiography. Have the indications changed during the 1980's?]. / La coronarographie normale. Les indications ont-elles varié au cours des années 1980?

If the indications of coronary angiography are well chosen, the percentage of normal coronary angiographies should decrease. The authors analysed 7858 primary coronary angiographies performed between 1981 and 1990 in patients without valvular or congenital heart disease. The second 5 years were compared to the first. The percentage of primary coronary angiographies decreased (63% vs 75%; p < 0.01), the percentage of women increased (21.7% vs 18.4%; p < 0.001), and the mean age increased (58.5 +/- 0.3 vs 53.9 +/- 0.3; p < 10(-9)). The lesions were less extensive: 16.3% triple vessel disease versus 24.2% (p < 0.001); 31.3% double vessel disease versus 28.1% (p < 0.02); 49.1% single vessel disease versus 44.2% (p < 0.001). The percentage of normal coronary angiographies remained constant: 20.2% in the second five years versus 19.9% in the first. Over the 10 year period, there was no significant difference one year from another. The percentage of normal investigations remained the same in men (15.7%), decreased in women (34.7 vs 40.1%, p < 0.04), remained constant in patients under 60 years of age (24.5 vs 23.8%), but increased in the more elderly (14.9 vs 10.2%; p < 0.001). The percentage remained unchanged in stable angina (19.6 vs 19.8%) and in unstable angina (12.3 vs 11.2%): it increased in cases of atypical chest pain (72.2 vs 54.3%; p < 0.01). Although, globally, the number of normal coronary angiographies was unchanged at 20%, the indications of this investigation were more selective in the younger patients, especially women, in the second five years, but coronary angiography was more commonly performed in elderly patients because of the possibility of benefiting from coronary angioplasty.

[Continuous electrocardiographic registration in occupational medicine]. / Enregistrement électrocardiographique continu en médecine du travail.

Continuous 24 hour electrocardiography (Holter method) was carried out during work time in 64 workers. They were divided into two groups: the first group comprised 34 subjects with either organic heart disease (coronary artery disease, valvular heart disease, operated coarctation, hypertrophic cardiomyopathy) or a documented arrhythmia without proven underlying cardiac disease; the second group comprised 30 subjects without known cardiac disease but complaining of symptoms suspected to be of cardiac origin or with isolated electrocardiographic abnormalities. At the end of the study we concluded that Holter monitoring is possible in subjects performing physical occupations even in difficult conditions. The trends of heart rate, especially mean heart rate calculated over 10 minute periods, confirmed the relationship between heart rate and the intensity of the physical activity. Atrial extrasystoles and episodes of supraventricular tachycardia were as common in the first as in the second group (20% and 18% respectively). This did not apply to ventricular extrasystoles: they were observed in both groups but were significantly more common in the first group (55% compared to 33%); ventricular extrasystoles, usually of a single configuration and isolated, were more common in the first group, especially amongst the coronary patients. Sinus node dysfunction was only observed in the second group (12.5%), in young subjects, and this occurred with only one exception at night. These findings support previous reports in the literature. However, the interpretation of these results is difficult because of the absence of well established normal values.

[Cardiac arrhythmia observed in 400 workers without obvious heart disease by Holter monitoring]. / Troubles du rythme cardiaque observés chez 400 salariés sans cardiopathie évidente par l'enregistrement Holter.

To obtain information on the cardiac rhythm characteristics of subjects without heart disease during their daily work, we examined the continuous 24-hour electrocardiographic recordings of 400 workers from 4 factories in Eastern France presenting with criteria of cardiac normality. Sex, age and socio-professional category were taken into account. Supraventricular extrasystoles were extremely common, being observed in 52 p. 100 of men and 39 p. 100 of women. In men, the frequency of these extrasystoles increased with age (p less than 0.001), and their number was less than 20 per 24 hours in 90 p. 100 of the cases. Ventricular extrasystoles were detected in 40 p. 100 of men and 32 p. 100 of women. They too were age-related, though not significantly. Their number was less than 10 per 24 hours in 68 p. 100 of the cases and 10 to 50 per 24 hours in 28 p. 100. These ventricular extrasystoles usually were monomorphous, regularly coupled (92 p. 100) and isolated. However, 2 attacks of tachycardia were discovered. Episodes of bradyarrhythmia (RR superior or equal to 1500 ms) were present in 25 p. 100 of men and 19 p. 100 of women. They occurred more frequently before the age of 35 than later (p less than 0.001) and the recordings confirmed that they were predominantly nocturnal. Recordings without "disorders of rhythm" were relatively rare (20 p. 100 of men, 28.5 p. 100 of women). Finally, there was no clear-cut correlation between the prevalence or characteristics of these various "rhythmic abnormalities" and the type of professional activity.

[Intrauterine insemination: spontaneous or medically-assisted ovulation?]. / Insémination intra-utérine: ovulation spontanée ou médicalisée?

Intrauterine insemination (i.u.i.) is usually proposed as the first-line therapy for infertility related to cervical factor, male and unexplained infertility. The overall success rate of i.u.i. is about 10-20% clinical pregnancies per cycle. i.u.i. may be performed in patients with or without prior controlled ovarian hyperstimulation (COH). The aim of COH is to closely monitor follicular growth in order to achieve a timely triggering of ovulation and i.u.i. Additionally, ovarian stimulation allows to increase the number of developing follicles. According to the review of previous prospective randomized studies and meta-analyses, it seems that: (i) when a cervical factor is involved, the advantage of COH in conjunction with i.u.i. is likely but has to be confirmed; (ii) in male infertility, COH with gonadotropins in conjunction with i.u.i. increases the clinical pregnancy rate by two. In this situation, the better the sperm parameters are, the more advantageous COH is; (iii) in unexplained infertility, COH in addition to i.u.i. improves the pregnancy rate but stimulation with clomifene citrate appears to be less effective than gonadotropins administration. Beside the sperm parameters, the success rate depends on both woman's age and degree of ovarian stimulation. Meanwhile, ovarian hyperstimulation exposes to the risk of multiple pregnancy and hyperstimulation syndrome. Increasing the number of preovulatory follicles from one to two allows to approximately double the pregnancy rate. However, there is clear evidence that getting three or more than three follicles exposes to a worrying risk of multiple pregnancy. At the present time, the successful outcome of i.u.i. should not be assessed by the clinical pregnancy rate any longer but by the singleton birth rate. Our therapeutic strategy for COH prior to i.u.i. should take into account woman's age, infertility duration and associated infertility factors. The objective in terms of preovulatory follicle number must be determined prior to the stimulation in order to optimise the cycle outcome with a singleton birth.

[Should infertile women with polycystic ovarian syndrome be treated with metformine?]. / Faut-il traiter par metformine les femmes infertiles présentant un syndrome des ovaires polykystiques ?

Polycystic ovary syndrome is a frequent endocrine disorder often associated with insulin resistance and hyperinsulinaemia which may play a role in hyperandrogenism and anovulation. The use of "insulin sensitizing" agents has been suggested to reduce insulin resistance and hyperandrogenism. In that respect, the use of metformin in polycystic ovary syndrome is reviewed. Although its mechanism of action is still unclear, metformin proved to be effective to restore cyclicity and spontaneous ovulation. The synergistic effect of clomiphene citrate and metformin was demonstrated in some studies, suggesting that metformin could be helpful for women with clomiphene citrate resistance. However, the potential effect of metformin administration for reducing hyperstimulation in women treated with exogenous FSH, or for preventing early miscarriages has to be confirmed. Here, we propose a guideline for the use of metformin, as an adjuvant therapy, to restore cyclicity and ovulation in women with polycystic ovary syndrome.