This thesis deals with the performance of a diagnostic protocol designed to determine the underlying causes of early fetal and perinatal deaths. It is subdivided into three chapters. The first chapter is a review of the literature. It surveys the underlying causes of fetal and perinatal deaths and the informativeness of different tests applied to assess these causes. The second chapter is a manuscrrpt describing the real performance of one of these protocols applied since 1982 in a geographlcally determined area. This area, located in the south east of France, covers annually 23,000 births. This descriptive study carried out on 1019 consecutive stillbirths and perinatal deaths shows the importance of both clinical information and necropsy among the overall tests. This chapter is preceded by an overview of the context and the objectives. In the third chapter, written as a classical chapter of a thesis, a decision tree presents the theoretical performance of each relevant combination of tests for the diagnosis only of fetal causes of death. The theoretical informativeness of each test was coded with the aid of two medical geneticists. Non fetal causes are not considered in this part of the study because the underlying objective of the clinicians who implemented the protocol was only to screen genetic causes of death. / Cette thèse se divise en trois chapitres écrits dans le cadre d'une étude d'évaluation de la performance d'un protocole de diagnostic des causes initiales de mortalité foetale précoce et périnatale. Le premier chapitre est constitué d'une revue de la littérature sur les causes initiales de mortalité et sur l'informativité des examens clinique et paracliniques à la naissance d'un enfant mort-né. Le deuxième chapitre est un manuscrit d'article décrivant la performance réelle d'un protocole de diagnostic mis en place en 1982 dans une zone géographique délimitée du sud est de la France couvrant 23 000 naissances annuelles. Cette étude descriptive porte sur 1019 décès consécutifs. Elle montre l'importance de l'information clinique et de l'autopsie parmi l'ensemble des examens. Elle est précédée d'une présentation du contexte et des objectifs. Le troisième chapitre est rédigé non plus sous la forme d'un article scientifique mais comme un chapitre de thèse classique. Il présente un arbre de décision évaluant la performance théorique de chaque combinaison des différents éléments du protocole. Le codage de l'informativité théorique de chaque élement inclus dans le protocole a été réalisé en collaboration avec deux experts en génétique médicale. Cette performance a été considérée uniquement pour la détermination des causes fœtales de mortalité. En effet, ce protocole mis en place à l'initiative d'une équipe de médecins pédiatres et généticiens, avait seulement pour objectif initiai le dépistage des causes fœtales de décès d'origine génétique et non celles d'origine maternelle ou obstétricale.

Prospective evaluation of symptomatic women with CA-125 and transvaginal ultrasound scan (TVUS) in the DOvE pilot project has resulted in a higher prevalence of invasive ovarian cancer as compared to screening the general population. The detected cancers also showed a trend of diagnosis in completely resectable stages. However, the false positive rate was high; 19% of patients underwent further investigation in absence of malignancy. Our objective was to limit the number of further interventions among false positive symptomatic women in DOvE.We developed a predictive model to help determine who, among patients testing positive in the first instance, required further investigation. The model was subsequently validated prospectively in 58 women.CA-125, endometrial thickness, postmenopausal bleeding, solid area within an ovarian mass and age predicted the need for further investigation. Upon ROC analysis, this model was 92% sensitive and 84.8% specific in predicting those patients with positive CA-125 and TVUS that truly required further investigation, at an optimal cutoff probability of 0.069. To maximize sensitivity (100%), the cutoff probability was 0.027, and the specificity 66.8%. When applied prospectively, the model was 100% sensitive and 82% specific by ROC analysis.Although a baseline false positive rate is inevitable given the limitations of such tests, our model can be used to triage symptomatic women with positive CA-125 and/or TVUS and has potential to alleviate the burden of false positive results. / L'évaluation des femmes symptomatiques avec un prélèvement sanguin pour le CA-125 et une échographie transvaginale dans le cadre du projet pilote DOvE a pu dépister un plus grand nombre de cancers ovariens invasifs comparé au dépistage de la population générale. De plus, ces cancers ont une plus grosse chance d'être diagnostiqués en stades complètement opérables. Par contre, le taux de faux positifs était élevé ; 19% des patientes ont du passer des tests supplémentaires suite à un résultat positif aux tests de dépistage en absence de cancer. L'objectif de l'étude courante est de limiter le nombre d'interventions supplémentaires chez les femmes symptomatiques ayant un test positif dans le cadre de l'étude DOvE. Nous avons développé un modèle prédictif pour aider à déterminer qui, parmi les patientes ayant un test positif en premier lieu, nécessitait vraiment des interventions supplémentaires. Ce modèle a ensuite été validé prospectivement sur une cohorte de 58 femmes. Le niveau de CA-125, l'épaisseur de l'endomètre, le saignement post-ménopause, une masse ovarienne présentant des régions solides et l'âge sont des prédicteurs significatifs du besoin d'investiguer plus loin un résultat positif. D'après l'analyse ROC, ce model est 92% sensitif et 84.8% spécifique pour prédire les patientes ayant un CA-125 et/ou échographie transvaginale qui nécessitent d'autres tests, et ce, a une probabilité optimale de 0.069. En l'appliquant prospectivement, ce modèle est 100% sensitif et 82% spécifique par analyse ROC. Malgré du fait qu'un taux de faux positifs de base soit inévitable étant donné les limites de ces deux tests, notre modèle pourrait être utile pour le triage des femmes symptomatiques ayant un CA-125 et/ou ETV positif et pourrait ainsi réduire le fardeau des résultats faux positifs.

Nodal, a morphogen in the transforming growth factor-beta (TGF-β) superfamily, is often characterized by its critical functions during embryogenesis. Recently however, essential components of the Nodal signaling pathway have been described in the uterus and implicated in the events that comprise mammalian reproduction. Despite these advancements, the expression, regulation and potential functions of Nodal in the maternal reproductive tract in facilitating successful pregnancy outcome have not been examined. In order to aid in the ongoing pursuit of elucidating the biological mechanisms that govern reproduction, and providing potentially invaluable information towards combating female infertility or pregnancy-specific complications, these unknown aspects of uterine Nodal signaling were explored. In Manuscript I, I present a detailed profile of Nodal expression and protein localization in the mouse uterus throughout pregnancy. Interestingly, Nodal expression produced a distinct banding pattern along the proximal-distal axis of the uterine horn at the time of embryo implantation that directly correlated with the inter-implantation space. Furthermore, blastocyst transfer experiments demonstrated that the embryo plays an integral role in directing uterine Nodal expression during implantation. Finally, during the later stages of reproduction, we observed that Nodal undergoes dynamic changes in expression during placental development. In Manuscript II, I introduce a novel, tissue-specific mouse strain with a conditional Nodal deletion in the reproductive tract of post-pubescent females. Nodal knockout mice exhibited a range of reproductive abnormalities that affected both early and late pregnancy. Strikingly, Nodal knockout females that established pregnancy ultimately experienced intrauterine growth restriction (IUGR) and preterm birth of the fetus, leading to neonatal mortality. Utilizing several approaches, we demonstrate that uterine Nodal deletion impaired placenta development, disrupted the delicate maternal-fetal interface, and contributed to premature induction of the parturition cascade. In Manuscript III, I examine the early reproductive phenotype, which resulted in severe sub-fertility of Nodal knockout females, and conclude that uterine Nodal deficiency leads to impaired oviductal transport, embryo implantation and endometrial decidualization. Together, these studies demonstrate the critical functions of maternal Nodal signaling during mammalian reproduction. / Nodal, un morphogène provenant de la superfamille TGF-b (transforming growth factor-beta), est souvent caractérisé par son rôle déterminant durant l'embryogenèse. Récemment, la voie de signalisation de Nodal a aussi été observée dans l'utérus et pourrait être essentielle durant la reproduction chez les mammifères. Malgré ces données récentes, l'expression, la régulation et les rôles de Nodal dans l'endomètre maternel durant différents stades de gestation n'ont pas été examinés. Afin d'élucider les signalisations biochimiques qui gouvernent les éléments essentiels à la reproduction, les aspects non-connus de la signalisation de Nodal dans l'utérus ont été explorés. Cette recherche a plein de potentiel pour contribuer à la découverte de nouvelles mesures pour combattre les taux d'infertilité et de complications de grossesse qui augmentent chez les femmes. Dans le Manuscrit I, je décris précisément l'expression de Nodal et sa localisation protéique dans l'utérus murin durant les différents stades de gestation. Il est intéressant de noter que l'expression de Nodal a révélé un motif distinct en forme de succession de bandes tout le long des extrémités proximales et distales de la corne utérine durant le temps d'implantation. Cette succession de bandes représentant l'expression protéique de Nodal est en corrélation directe avec les espaces séparant les sites d'implantation. Des techniques expérimentales incluant le transfert de blastocystes ont démontré que l'embryon joue un rôle intégral durant le processus de l'implantation en dirigeant l'expression utérine de Nodal. Finalement, durant les derniers stades de gestation, on a observé des changements dynamiques dans l'expression de Nodal durant le développement du placenta. Dans le Manuscrit II, j'introduis une nouvelle souris transgénique dans laquelle Nodal est supprimé conditionnellement dans des tissus reproductifs spécifiques de femelles post-pubescentes. Ces souris knock-out de Nodal ont exhibées plusieurs sortes d'anomalies reproductives qui ont eu des effets au début et en fin de gestation. Les femelles knock-out de Nodal qui ont pu maintenir une grossesse établie ont cependant souffert de restrictions de la croissance intra-utérine et d'accouchements prématurés, menant à la mortalité néonatale. En utilisant plusieurs approches scientifiques, nous avons démontré que l'invalidation de Nodal dans l'utérus a perturbé le développement du placenta, a abîmé l'interface mère/fétus délicate et a contribué à l'induction prématurée de la parturition. Dans le Manuscrit III, j'examine le phénotype au début de la reproduction dans les souris transgéniques invalidés de Nodal qui est caractérisé par la sous-fertilité sévère. J'ai conclu que le déficit de Nodal dans l'environnement utérin mène à la perturbation du transport oviductal, de l'implantation de l'embryon et de la décidualisation de l'endomètre. Ensemble, ces données démontrent les fonctions cruciales des voies de signalisations Nodal maternelles durant la reproduction des mammifères.

Atrial natriuretic factor (ANF) is a smooth muscle relaxant. This thesis examined the effects of ANF on rat uterus. ANF inhibited the motor activity of non-gravid but not of the gravid uterus. This decrease in the tocolytic effects of ANF during pregnancy correlated with an increase in plasma progesterone. The tocolytic activity of ANF was also inhibited by exogenous progesterone. In contrast, the sensitivity of the uterus of both virgin and pregnant rats was significantly increased by the progesterone receptor antagonist, RU486. The inhibition of the tocolytic activity of ANF by ovariectomy was reversed by estrogen. Refractoriness to the tocolytic activity of ANF was accompanied by decreases in myometrial ANF receptors and in the stimulant effects of ANF on myometrial particulate guanylate cyclase activity and cyclic guanosine 3$ sp prime$:5$ sp prime$-monophosphate. In contrast, estrogen and RU486 increased myometrial ANF receptors. It is concluded that the exposure of the myometrium to progesterone during pregnancy results in the down-regulation of myometrial ANF receptors, and in turn in a decrease in its tocolytic and biochemical effects on the uterus; this may be physiologically important for the progression of pregnancy and parturition.

Estradienolone (ED, 17beta-hydroxy-[1,5]-estradien-3-one) is a novel steroid hormone identified in pregnant women. It is an isomer of estradiol which binds the progesterone receptor and sex hormone binding globulin with high affinity. Since levels of ED remain high throughout pregnancy and decrease in association with term or preterm labour, ED may be involved in the maintenance of pregnancy. The objectives of the present study were to, (i) purify ED from pregnancy samples in quantities sufficient for chemical analysis to confirm its structural features, and (ii) identify its binding proteins and receptors. Our results show that ED binds the novel methyltrienolone (R1881) binding protein of JEG-3 cells with higher affinity than any other natural steroids tested. Furthermore, ED is able to inhibit transcriptional activity of the estrogen-receptor-related receptors alpha and gamma, suggesting that ED may be the natural ligand of these orphan receptors. ED is also able to activate the xenobiotic receptor SXR. Chemical analysis of the fine structural features of purified ED is in progress.

Preterm birth is the major clinical issue in maternal-child health in the developed and developing world. Even though multiple factors have been identified as causes of spontaneous preterm labour, the specific events leading to preterm birth are still poorly understood. Our group has previously identified a novel endogenous steroid, estradienolone (ED), and reported that the plasma and placental levels of ED remain high during pregnancy and decrease in association with term and preterm labour. Since ED appears to have progestin-like properties and is a natural ligand of estrogen receptor-related orphan receptors, ED may play a role in the maintenance of pregnancy or its decrease in the initiation of parturition. To fully analyze the unique biological properties of ED, availability of large quantities of ED by chemical synthesis is required. Although mass spectrometric analysis revealed an estradienolone structure, details such as position of double bonds and absence of other subgroups are necessary before chemical synthesis can be attempted. The objective of the current project was to prepare sufficient quantities of pure ED for detailed structural analysis. Early studies focused on purifying unconjugated ED from hydrolysed pregnancy urine since it is an abundant source of sulfate-conjugated ED. However, the yield of unconjugated ED was low probably due to its relatively unstable nature. Several methodologies were therefore developed for the isolation of ED sulfate as it is a more stable form of ED. Availability of sufficient quantities of ED or ED sulfate are critical for defining the detailed structure (using methods such as nuclear magnetic resonance), of this novel steroid. / Les naissances prématurées sont un problème clinique majeur en maternité/pédiatrie dans les pays développés et en voie de développement. Bien que de nombreux facteurs de risques d'accouchement prématuré spontané aient été identifiés, les évènements spécifiques conduisant à une naissance avant terme sont encore mal compris. Notre groupe a identifié précédemment un nouveau stéroïde endogène, l'estradienolone (ED), et a montré que les niveaux placentaires et du plasma d'ED restent élevés pendant la grossesse et chutent en association avec le travail prématuré ou à terme. Puisqu'ED possède des caractéristiques semblables à la progestérone et est un ligand naturel des récepteurs orphelins associés à l'œstrogène (ERR), il est possible qu'ED joue un rôle dans le maintien de la grossesse. Sa diminution entrainerait alors le déclenchement de la parturition. Afin de finir de caractériser les propriétés biologiques uniques d'ED, il nous faut le synthétiser chimiquement en grandes quantités. Cependant, bien que l'analyse par spectrométrie de masse ait indiqué qu'ED a une structure d'estradienolone, la position des liaisons doubles et la présence ou absence d'autres sous-groupes restent à déterminer avant de pouvoir effectuer une telle synthèse chimique d'ED. L'objectif de ce projet était donc de préparer des quantités suffisantes d'ED pur en vue de réaliser une analyse structurale détaillée. Nous avons d'abord essayé de purifier ED non conjugué après hydrolyse d'urine de femme enceinte, puisque c'est une source importante d'ED conjugué à un groupement sulfate (sulfate d'ED). Le faible rendement d'ED non conjugué (probablement dû à sa nature relativement instable) m'ont conduit à développer d'autres techniques pour l'isoler le sulfate d'ED car cette forme est plus stable. La disponibilité de quantités suffisantes de sulfates d'ED ou d'ED non conjugué est essentielle pour l'obtention de la structure détaillée de ce nouveau stéroïde (en employant des méthodes telles que la résonance magnétique nucléaire).

The role of C19 steroids in the human endometrium is at present unclear. In order to gain an insight into their action, radioimmunoassay procedures were developed which had sufficient specificity and accuracy to measure testosterone, 5α-DHT, oestradiol, progesterone and androstenedione in endometrial samples. Amounts of androstenedione were greater (range 1.2-20.8 ng/mg tissue) than other steroids. Samples were obtained from patients presenting with a variety of conditions: subfertility, postmenopausal bleeding, dysfunctional uterine bleeding and abdominal pain. Patients admitted for sterilisation were used as normal controls. A significant positive correlation (r = 0.80) was found between the levels of testosterone and 5α-DHT measured in the same tissue which suggests the presence of a 5α reductase enzyme. No relationship was observed in tissue steroid concentration and age of the patients. Steroid concentrations were found to be high in tissues obtained from patients with endometrial carcinomas whereas progesterone concentration being low in subfertiles. The oestrogen, progesterone and androgen receptor levels of endometrial tissues from subfertile women were also determined using the DCC technique and not the procedure based on protamine sulphate precipitation since endometrial tissue available was very small. No correlation was found between receptor binding sites and day of cycle for any of the three steroids analysed; nor was there any correlation between age and receptor binding sites. A cyclic variation followed by normal women was seen in the oestrogen and progesterone receptor concentrations in the menstrual cycle. Such a variation was also observed in subfertile women on clomiphene citrate therapy. It is concluded that normal endometrium contains measurable quantities of androgens and that a receptor for 5α-DHT is present. The difference in steroid concentrations between normal and pathological states suggest that C19 steroids may be induced in the development of abnormalities.

Breast cancer is the most common form of cancer among women in the United Kingdom, and there is considerable investment in research to identify the causes of breast cancer and the best means of diagnosis and treatments. The randomised controlled trial is the principal method used for evaluating diagnostic and treatment options. Trial organisers depend on recruitment of sufficient numbers of patients in order that the results are statistically significant and generalisable, but accrual to cancer clinical trials is poor. This research analyses factors affecting the accrual of women to two breast cancer trials, the British Association of Surgical Oncology (BASO) II trial (a treatment trial) and the International Breast cancer Intervention Study (IBIS) (a prevention trial). The aims were to identify the factors affecting the recruitment of women to breast cancer clinical trials from the surgeons' and multi-disciplinary teams' perspectives and, importantly, from the perspectives of women approached to participate in clinical trials, and their reasons for participation, or non-participation in the trials. There were three phases to the study using multiple methods. In the first phase quantitative methods were used in the form of a questionnaire, sent to consultant surgeons responsible for collecting audit data regarding breast cancer in the United Kingdom. The second and third phase incorporated qualitative methods of data collection; the second phase included in-depth interviews with multi-disciplinary teams; and the third phase involved focus group and individual interviews with women approached to join a breast cancer clinical trial. These three phases were carried out in both the trials examined. The findings contribute to the debate and knowledge of the recruitment of women to breast cancer clinical trials in a number of ways. Firstly, by including the views of all the key stakeholders concerned with breast cancer clinical trials. Secondly, by highlighting the factors affecting recruitment to these two breast cancer clinical trials. Thirdly, by making recommendations on methods to enhance recruitment.

This thesis examines the function of discursive paradigms in the process of subjectivisation and the formulation of objects in the development of the human sciences. The history of childbirth practices exemplifies the operations of paradox and paradigm, and of epistemic changes and continuities, in relation to medical, ethical, and pedagogic discourses. The recent past has brought rapid change in the practices and outcomes of parturition with regard to technologisation, and the improvement in mortality rates. The achievement of technological childbirth has a complex and paradoxical history, and should be understood other than as an inevitable and progressive phenomenon of scientific endeavour, or as a conspiracy of patriarchy which victimises and subjugates women as a matter of intentionality. The histories of the parturient and of the midwife are only partially linked. An examination of childbirth history reveals some of the implications of phallogocentricity for the history of women and for the constitution of gender and gender relations. Midwifery has its own unique but unmistakeable place in the historical discourse of pathologisation and professionalisation - and cannot be regarded simply as an arena of masculine appropriation. The mechanisms for change in parturial practices have been developing to facilitate the modifications of recent history since around 1800, but there are discursive resonances which are linked also to changes in pedagogic organisation which began in the Middle Ages. Further, in order to analyse and evaluate the history of parturition over the past two hundred years, it is necessary to examine the paradigmatic structures based upon dialectical reasoning which have dominated the development of the human sciences since antiquity. Childbirth provides examples of many historical exigencies which informed a panoply of disparate effects, but it is also in many respects unique and anomalous. An exploration of the operations of power, knowledge and influence in this sphere, reveals as much in terms of its resistances as its susceptibilities, to medical appropriation. The history of childbirth is unusual insofar as the technologies and innovations that developed in relation to it, were in fact, slow to be implemented. Evidence of such paradigmatic dysjunction is provided by the examples of the use of forceps, asepsis and anaesthesia in the nineteenth century. This thesis addresses aspects and effects of professionalisation, and the increasingly disciplinary implications of expert discourses for the pregnant and parturient woman in the twentieth century.

"I know that every day I am gaining experience ... learning more" (Int. 6(a)) This thesis examines the social practices and associated learning that shape the meaning of midwifery for new members of the profession. In doing so it explores the extent to which the implications of practice either liberate or circumscribe midwives' identity formation. The thesis further suggests how this identity formation may impact upon commitment to a long term career in midwifery. The theoretical framework for this thesis acknowledges that continuing professional development and evidence of recognised learning activity is, for all midwives, a professional requirement. However, less attention has historically been paid to the unstructured, unintended and relatively informal learning that occurs within and throughout midwives' involvement in everyday practice. It is through these forms of learning, and drawing upon data elicited through surveys, interviews and diaries, that this thesis seeks to make a contribution. Using a social model of learning, particularly through Wenger's (1998) work on communities of practice, the development of identity is presented as a negotiated process mediated to a greater or lesser degree by workplace relationships. Whilst relationships with pregnant women form an important element of this process, the thesis argues that collegial relationships generally assume greater importance and impact on the development of identity and meaning for newly qualified midwives. By situating the everyday experiences of newly qualified midwives within a broader theoretical debate about social learning, identity and the making of meaning, this thesis suggests that the contemporary 'doing' of hospital based midwifery remains within what are fairly narrowly prescribed, contested, yet firm boundaries. The development, existence and negotiation of these boundaries is central to the space which pregnant women, midwifery and midwives can occupy. These boundaries are simultaneously hierarchical, intra professional and personal. Furthermore, in practice, these boundaries are frequently unclear and rapidly changing. Whilst this contributes to a potentially dynamic opportunity for identity formation, the thesis demonstrates how this also transpires to contribute to an unstable, frustrating and frequently challenging context particularly for newly qualified members of the profession. Overall, this thesis contributes to an understanding of the development, or lack of development, of midwifery practice at theoretical, conceptual and practical levels. Viewing practice as social learning offers a new perspective on the opportunities and challenges inherent in the current model of care. Simultaneously it suggests a new perspective on the recruitment crisis faced by the profession and accordingly the opportunity for new potential solutions.