Background: Although intrapartum hypoxia-ischaemia is an important cause of death and permanent brain injury, current available methods for the detection of damaging fetal hypoxia are unsatisfactory and unreliable. Electronic fetal heart rate monitoring (EFM) is considered to be the "gold standard" for intrapartum fetal surveillance. However, monitoring of the fetal heart rate provides an indirect measure of fetal hypoxia and provides little indication of the adequacy of cerebral perfusion. Consequently, EFM has a false positive rate of 99.8% in the detection of fetuses that subsequently develop cerebral palsy. A direct consequence of the poor specificity of fetal heart rate monitoring is a high rate of unnecessary Caesarean sections with associated fetal and maternal morbidity. Most fetuses subjected to intrapartum hypoxia will be protected from brain injury by appropriate changes in cardiovascular distribution. It is the aim of fetal surveillance to detect the minority of fetuses in whom this response is absent and who are at risk of permanent brain injury. Intrapartum fetal pulse oximetry is a promising new method of fetal surveillance, enabling measurement of fetal arteriolar saturation but the technique provides no direct information on cerebral oxygen delivery. Intrapartum measurement of fetal cerebral saturation and changes in blood volume has been described using conventional near infrared spectroscopy (NIRS). However, the clinical relevance of these values may be limited. This is because these values are derived from changes in the concentrations of oxyhaemoglobin (HbCh) and deoxyhaemoglobin (Hb) from an arbitrary baseline. Furthermore, the contribution of artefact to NIRS measurements of Hb and HbC>2 changes, arising from possible changes in the geometry of the NIRS fetal probes during uterine contractions, has not been clearly defined. Using novel methods of collection and analysis of NIRS data, the technique of Intensity Modulated Optical Spectroscopy (IMOS) has the unique potential to provide direct information on fetal cerebral oxygenation and perfusion during labour from measured absolute values of fetal cerebral Hb02 and Hb. Furthermore, the technique of IMOS has the potential to provide more information on the contribution of probe movement during uterine contractions to conventional NIRS data.;Aims: The aims of this project were therefore to use this new technique of intensity modulated optical spectroscopy to (a) provide the first measurements of absolute cerebral blood volume and cerebral saturation in healthy normoxic human fetuses during labour and (b) to compare these values with those calculated from fetuses that develop hypoxia-ischaemia during labour and (c) to assess the contribution of probe movement during uterine contractions.;Methods: After assessing and optimising the technical performance of a specially designed and constructed intensity modulated optical spectrometer, a specially designed optical probe was placed against the scalp of 29 fetuses after rupture of amniotic membranes during labour and connected to the spectrometer.;Results: Of these 29 fetuses, data were collected from 18 fetuses during the first and second stage of labour through to delivery. Of these 18, data was suitable for analysis in 10 of these fetuses. In these 10 fetuses, a mean (+/-1 S.D.) value of cerebral saturation of 59 +/-12 % and a mean absolute cerebral blood volume of 2.8 +/-1.0mls/100g over 3 uterine contractions were derived from the mean concentrations of Hb and Hb02 of 30 +/-18 and 46 +/-21 umol/1, respectively. Concentration changes rather than artefact appeared to dominate the NIR signal in the calculation of these values.;Conclusion: This work has provided the first measurements of absolute values of fetal cerebral oxygenation and of cerebral perfusion, whilst the contribution of artefact to the data, certainly in the healthy fetus, appears to be negligible. However, despite these advances in near infrared technology and knowledge of intrapartum fetal cerebral haemodynamics, the number of fetuses studied with near infrared spectroscopy, in particular IMOS, remains small. In order for IMOS to be subjected to larger studies to assess it's usefulness as a realistic adjunct to fetal heart rate monitoring, advances in the technology are still required.

International research suggests that fear of childbirth is associated with adverse clinical outcomes for mothers and babies. Much less data is available from within the United Kingdom and it is proposed that this has occurred because of the lack of an English language questionnaire to measure fear of childbirth amongst this population. This study was designed to bridge this gap in the evidence. In the qualitative phase 19 women and 19 men were interviewed and the data was analysed using the sense of coherence (Antonovsky, 1979) theoretical framework. The findings informed the development of a new questionnaire, the Fear of Childbirth Universal Scale (FOCUS), to measure fear of childbirth amongst both pregnant women and their partners. Mean scores on the new questionnaire were used to determine the impact of fear of childbirth on clinical outcomes for mothers and their babies. Women feared for their own and their baby's safety during the birth process and lacked confidence in their ability to give birth safely. Men feared a very painful or traumatic birth would have a negative impact on their partner's mental health. Both women and men identified medical interventions in birth as a means to keep the mother and baby safe. The questionnaire was found to be reliable to measure fear of childbirth amongst both pregnant women and their partners. Women and their partners who used midwifery-led types of care had lower levels of fear of childbirth than those who used medically-led care. Fear of childbirth amongst both women and men was associated with increased use of medical interventions and adverse clinical outcomes such as increased incidence of induction of labour, epidural use during labour, emergency caesarean section and longer stays in hospital. Babies of fearful parents were less likely to be breastfed.

No description available.

No description available.

This study examines mother's and father's accounts of their experiences during the post-natal period in an attempt to understand distress following childbirth within an interactional framework. Four couples were recruited through the Meet-A-Mum Association and through professional contacts. All the mothers had been given a diagnosis of post-natal depression by their GPs. The fathers all reported experiencing distress since the birth of their child and one had been given a diagnosis of depression by their GP. Each couple was interviewed using a semi-structured interview format, first together and then separately. The participants' accounts were analysed using a discourse analytic approach. The women's varied experiences of distress were labelled by professionals as post-natal depression and explained within a biomedical framework which precluded the consideration of alternative social, psychological or political explanations. However, the women were able to identify a number of alternative explanations for their difficulties. This, together with the finding that the fathers experienced similar distress during the post-natal period, suggests that the bio-medical model of distress following childbirth is too simplistic. Undermining discursive practices and negative cycles of interaction, operating within the parental relationship, were identified in the participants' accounts and implicated as significant factors in the development and maintenance of both the mothers' and fathers' distress. The effects of the dominant constructions of parenthood, depression, masculinity, and femininity on the participants' identity and experiences are analysed. Lastly, the implications of the findings for future research and clinical practice are discussed.

Abstract Background: Approximately 11 % of women give birth with the aid of a ventouse or forceps in the UK. These deliveries are associated with significant maternal and neonatal morbidity. Inexperience of the operator is a contributory factor towards the morbidity. Objectives: 1. To define the technical and non technical skill of an operative vaginal delivery in simulation and to validate these skills in the clinical setting. 2. To develop and validate objective assessment tools for evaluation of the skills of an operative vaginal delivery. Setting: Two university teaching hospitals (St. Michael's Hospital Bristol and Ninewell's Hospital, Dundee). Participants: 1. Defining the skills: Ten obstetricians and eight midwives identified as experts in conducting or supporting operative vaginal deliveries. Eighteen women were recruited for validation of the skills in the clinical setting. 2. Validation of assessment tools: 28 obstetricians of varying level of experience. Methods: 1. Defining the skills: Semi structured interviews were carried out using routine clinical scenarios. The experts were video recorded conducting operative vaginal deliveries in a simulation setting. The interviews and video recordings were transcribed verbatim and analysed using thematic coding. The anonymised data were independently coded by three researchers and compared for consistency of interpretation. The experts reviewed the coded interviews and video data for respondent validation and clarification. The themes that emerged following the final coding were used to formulate a list of skills and to develop the assessment tools. Four real life operative births were video recorded and the videos reviewed to validate the findings of simulation. 2. Assessment tools: A formative assessment tool for technical skills was developed and the construct validity was assessed by using the assessment tool to evaluate the skills of six expert and seven novice obstetricians video recorded conducting operative vaginal birth in simulation. A script concordance test was developed for assessment of decision making skills and construct validity was assessed by recruiting 28 obstetricians of varying level of experience. These obstetricians completed a 59 part questionnaire. Results: 1. Defining the skills:The final skills list included detailed technical skills and non technical skills required for conducting an operative vaginal delivery. The combination of semi structured interviews and simulation videos allowed the formulation of a comprehensive skills tool for future evaluation. 2. Assessment tools: The formative assessment tool was a valid tool for assessment of technical skills with a significant T test of 5.01 (p= 0.001, 8.6-19.1).The script concordance test did not show a significant improvement with experience as the ANOVA test of variance amongst the groups was not statistically significant (F = 0.22). Conclusion: This explicitly defined skills list and formative assessment tool is a valuable first step to aid training in operative vaginal delivery.

The importance of the appropriate timing of parturition is highlighted by the fact that preterm labour accounts for 85% of the deaths of normally formed babies. In addition, there are clinical situations where induction of labour is required. Attempts to reduce the incidence of preterm labour and facilitate induction require an understanding of the normal processes of labour at term. In this thesis the physiology of parturition is considered, with emphasis on prostaglandin biosynthesis and metabolism, and the regulation thereof, processes which are thought to be pivotal in the mechanism of labour. The physical and biochemical changes associated with cervical ripening are discussed, as are mediators of this process. Finally, the current understanding of ovine parturition and potential similarities with humans is reviewed. The laboratory studies described employ the techniques of explant and cell culture of fetal membranes, namely amnion and chorion, to investigate firstly the changes in synthesis and metabolism of prostaglandins E2 and F2a (PGE2, PGF2a) that occur within these tissues in association with labour. Prostaglandin production by amnion is increased without any effect on metabolism by chorion. The effect of amniotic fluid on prostaglandin synthesis and metabolism in cell culture was then explored, and, having demonstrated that amniotic fluid from labouring women stimulates PGE2 and PGF2a production, the mechanisms controlling the response to amniotic fluid were investigated, and found to be dependent on new protein synthesis and protein kinase C. In the clinical situation pharmacological ripening of the cervix was studied in two randomised, placebo-controlled clinical trials. The efficacy of recombinant human relaxin and mifepristone (RU 486) was investigated in women with an unfavourable cervix, modified Bishop score < 4, in whom induction of labour was indicated. Vaginal administration of relaxin (1,2 and 4 mg) was without effect on cervical ripening. The first part of a dose finding study with mifepristone demonstrated that a dose of 50 mg may have some preparatory effect on the cervix with regard to ripening, but that a higher dose is required for successful induction of labour.

No description available.

Fetal head moulding is a phenomenon that happens during the process of human childbirth. Due to the highly deformable fetal scalp being in contact with the maternal anatomy, the shape of the fetal head changes. This can be beneficial when the fetal head dimensions are very similar to the dimensions of the female pelvis hence allowing the baby to progress safely through the birth canal. Conversely, excessive head moulding may have serious effects on the baby's wellbeing. The first part of this thesis presents a computer-based finite element model of fetal head moulding as an improvement on previously developed models. The second part of the research focuses on another cause of potentially excessive fetal head moulding, i.e. the incorrect use of obstetric instruments including the obstetric forceps and the ventouse (vacuum extractor). The degree of damage that may be caused by incorrectly placing a forceps (i.e. asymmetric placement of the blades) or a ventouse (i.e. placement on top of soft parts of the skull such as the fontanelles) was assessed by means of finite element analysis after developing a set of software tools to facilitate these experiments. The fi�nal results of this research included: an improved and more realistic model of fetal head moulding under conditions of normal delivery, and results that reveal the great potential of severe damage that obstetric forceps and/or the ventouse may cause to the baby's head when applied incorrectly.

Many problems can occur during childbirth which may lead to instant or future morbidity and even mortality. Therefore the computer-based simulation of the mechanisms and biomechanics of human childbirth is becoming an increasingly important area of study, to avoid potential trauma to the baby and the mother throughout, and immediately following, the childbirth process. Computer-based numerical methods, such as the Finite Element Method, have become more widespread to simulate biological phenomena over the last two decades or so. One of the important aspects of such methods is them being able to accurately model the underlying physics and biomechanics of biological processes. In the case of the childbirth process, an important role is played by the fetal head and its motion as it is being born. The most important manifestations of the head’s motion are described as the cardinal movements. Being able to model the cardinal movements in a computer-based model of the human childbirth process is compulsory as they occur in almost every normal delivery. Many existing simulations use reverse-engineered approaches to model the cardinal movements by imposing pre-defined trajectories that approximate a real childbirth. These approaches lack physical accuracy and are unable to extend the simulation to unseen scenarios where for example the childbirth process does not develop normally. To create a simulation software capable of simulating realistic, including unseen, scenarios, and which does not make any pre-simulation assumptions about the cardinal movements, a physical and forward-engineered approach in which the motions of the head are determined by the underlying physics, is required. This thesis presents a simulation system where the physical behaviour of the fetal head is modelled during the second stage of childbirth. Accurate models of the fetal head and trunk, the maternal uterine cervix, bony pelvis and pelvic floor muscles, were created. Some of these are considered to be rigid bodies in the simulation (fetal head, trunk and maternal bony pelvis), whereas others are considered to be deformable (maternal uterine cervix and pelvic floor muscles). The Finite Element Method (FEM) is used to model the deformable tissues by implementing the Total Lagrangian Explicit Dynamics (TLED) approach on the GPU. The combined TLED/contact mechanics method was first tested on simple hyperelastic objects. Following successful validation, the interaction between the fetal head and the deformable tissues was evaluated using a projection based contact method in conjunction with TLED. Several experiments had to be done to find the required set of factors contributing to the occurrence of the cardinal movements. These steps are reported in the thesis as well as the results of the final experiments which do exhibit the key cardinal movements of a normal childbirth process, marking the successful, and key, contribution of this thesis. The GPU based acceleration allows running the simulation in near real-time, which makes it possible to create interactive simulations for training purposes of trainee obstetricians and midwives. The simulation system presented in this work is also the first step towards a fully patient specific system that would allow clinicians to diagnose and/or predict adverse scenarios of childbirth based on the MRI scans of real pregnancies prior to labour.