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1
Overton, Timothy Graeme. „Minimally invasive prenatal diagnosis“. Thesis, Imperial College London, 2000. http://hdl.handle.net/10044/1/7869.
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Турова, Людмила Олександрівна, Людмила Александровна Турова, Liudmyla Oleksandrivna Turova und W. A. Alsaedi. „New methods in prenatal diagnosis“. Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/32308.
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The development of genotyping and sequencing techniques has been dramatic during the recent years. Now it is possible to obtain a full view over an individual’ s genetic landscape in the form of a million common single-nucleotide polymorphisms (SNPs) in single and affordable experiments.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/32308
3
Crang-Svalenius, Elizabeth. „The use of routine ultrasound in pregnancy with special reference to normal and abnormal foetal growth, information and informed choice and the womens' experiences of the prenatal diagnostic aspects /“. Lund : Lund University, Dept. of Obstetrics and Gynaecology, University Hospital, 1997. http://catalog.hathitrust.org/api/volumes/oclc/39072830.html.
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4
Leung, Kwok-yin, und 梁國賢. „Prenatal ultrasound prediction of homozygous α⁰-thalassemia“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B47454039.
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Homozygous α0-thalassemia is a serious autosomal recessive disorder with
poor fetal outcome and severe maternal complications. Conventionally, prenatal
diagnosis is performed by an invasive test. A non-invasive approach using serial
ultrasonography can effectively reduce the need for invasive tests in unaffected
pregnancies.
For two-dimensional ultrasound prediction, a total of 777 at-risk fetuses were
studied from 12 to 20 weeks between 1995 and 2006. At 12–15 weeks’ gestation, the
highest sensitivity (98.3%) was achieved by the combination of fetal cardiothoracic
ratio (CTR) and/or middle cerebral artery peak systolic velocity (MCA-PSV) at a
false-positive rate of 15.8%. At 16–20 weeks’ gestation, the sensitivity of CTR was
100.0%, but the false-positive rate was 5.2%. In contrast, the false-positive rate of
MCA-PSV alone was 1.4% and that of the combination of CTR and MCA-PSV was
0%, although their sensitivities were less than 65%.
In a cross-sectional retrospective study of 546 samples at-risk and control (268
fetal and 278 neonatal cord blood), the degree of anemia was only mild in 27.5% of
the affected fetuses (see chapter 3 for definition of mild anemia). Because MCA-PSV
is not very predictive of mild anemia, this may be one of the reasons why MCA-PSV
is not very sensitive in predicting an affected pregnancy.
A total of 832 at-risk pregnancies were studied using same noninvasive approach
at Maternal and Neonatal Hospital of Guangzhou (MNH) and Tsan Yuk Hospital
(TYH). The overall sensitivity and specificity of the noninvasive approach was 100%
and 95.6% respectively. At MNH, the need for an invasive test was reduced by 78.6%,
and all the affected pregnancies were diagnosed before 24 weeks’ gestation. After
adequate training and monitoring the quality of the subsequent ultrasound
examinations, the results achieved at MNH were comparable to TYH, with at-risk
pregnancies including the affected ones being seen at a more advanced gestation at
MNH.
In a retrospective review of 361 women at risk of carrying an affected fetus, 311
(86.2%) opted for the non-invasive approach using CTR and/or placenta. The cost
saving of this non-invasive approach was relatively small (HK$ 2,651) in comparison
to the cost of the whole prenatal screening program. On the other hand, the
non-invasive approach was more expensive than the direct invasive approach for low
MCV couples, as well as couples discordant for α-thalassemia and β-thalassemia.
ages. These results support the adoption of non-invasive approach in which routine
invasive test or karyotyping is no longer performed.
A total of 106 at-risk pregnancies and normal controls were prospectively studied
using three-dimensional ultrasonography. Placental volume (PV) at 11-14 weeks, and
PV/CRL quotient at 9-14 weeks’ gestation of affected pregnancies were significantly
greater than unaffected pregnancies (P<0.05). Using a cut-off point of 1.2ml/mm for
PV/CRL quotient to predict an affected pregnancy, the sensitivity, and specificity was
96.2%, and 100.0% respectively.published_or_final_version
Obstetrics and Gynaecology
Master
Doctor of Medicine
5
Miller, Chloe Louise. „A comparison of attitudes towards prenatal diagnosis and pre-implantation genetic diagnosis“. Thesis, University of Leeds, 2010. http://etheses.whiterose.ac.uk/1083/.
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Technological advances in prenatal screening and diagnosis mean that it is now possible to test for a wide range of congenital conditions (Hewison et al., 2007). Traditionally testing has been carried out during pregnancy (prenatal diagnosis, PND). However, advances in technology have made it possible for diagnosis of an embryo created through in vitro fertilisation, prior to implantation into the womb (pre-implantation genetic diagnosis, PGD). This means that women can avoid the birth of a child with a genetic condition without the stress of terminating a pregnancy. This raises questions about what women want from reproductive technologies, as it means they are making decisions based not only on the condition diagnosed but also on the technology used to test. Two studies were carried out to examine this further. In the first study, 216 participants completed a questionnaire either based on PND or PGD. Participants were asked whether they would terminate a pregnancy (PND condition) or avoid implantation (PGD condition) following diagnosis of five different genetic conditions, ranging in severity. The results suggest an interaction between the technology (PND or PGD) and the severity of the genetic condition diagnosed, such that for the most and least severe conditions, the number of people choosing to terminate/avoid implantation was similar for the PND and PGD groups. However for conditions in the middle range of severity significantly more people said they would avoid implantation. A within subjects interview study was carried out to explore this further and thematic analysis identified a number of themes that influenced participants’ responses. Overall, the results suggest that PGD may be more acceptable for women in some cases. Women considering diagnoses are likely to benefit from detailed information about both PND and PGD in order to make a fully informed decision as to which is best for them.
6
Lee, Sansan. „Genetic counseling perspectives on prenatal array CGH testing“. Waltham, Mass. : Brandeis University, 2009. http://dcoll.brandeis.edu/handle/10192/23259.
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7
Azri, Stephanie. „Prenatal Diagnosis and Psychosocial Support: A Study about the Impact of Psychosocial Support on Women’s Wellbeing Following an Adverse Prenatal Diagnosis“. Thesis, Griffith University, 2017. http://hdl.handle.net/10072/366774.
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Prenatal diagnosis testing, whether a woman chooses to terminate her pregnancy or carry to term after an adverse prenatal diagnosis, comes with long term, complex implications which include psychiatric, emotional and social problems (Black & Sandelowski, 2010; Fonseca, Nazare & Canavarro, 2012; Howard, 2006, Korenromp, Christiaens, Bout, Mulder, Hunfeld & Bilardo, 2005; Lathrop & VandeVuss, 2011a; Taylor, 1998).
A variety of strategies are utilised by professionals to support women prior to the decision-making process, at the point of decision-making and after the termination or birth following an adverse prenatal diagnosis. Understanding the impact of specific types of support has been limited. Additionally, it appears that attempts to develop regulatory standards and models for adequate psychosocial support have failed to date (Abramsky, 2003; Howard, 2006; Shiloh, 1996). This study focused on the impacts of particular types of support (counselling, case management, support groups, friends/family and/or written resources) on the anxiety, guilt and decisional conflict of women after a prenatal diagnosis.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Human Services and Social Work
Griffith Health
Full Text
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LaPan, Amy C. „Prenatal testing, birth outcomes, and views of social workers“. online access from Digital Dissertation Consortium, 2005. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?3202790.
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9
Leung, Wing-cheong, und 梁永昌. „Rapid aneuploidy testing or traditional karyotyping, or both, in prenatal diagnosis“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B4520553X.
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Paal, Andrea M. „Parents' Informational Needs Following Prenatal Diagnosis of Spina Bifida“. University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1276976280.
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Tedgård, Ulf. „Prenatal diagnosis of haemophilia psychological, social and ethical aspects /“. Malmö : Dept. of Pediatrics, University Hospital of Malmö, University of Lund, 1999. http://catalog.hathitrust.org/api/volumes/oclc/57455671.html.
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12
McDougall, Christopher W. „Uncertain risks, responsibilities & regulations : the ethics & control of PGD in Canada“. Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33915.
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The current state of preimplantation genetic diagnosis technology is presented, as are the biological principles and medical procedures that make it possible. The arguments of both proponents and those with social and ethical reservations about the broader implications of the technique are carefully reviewed, and the limitations of the dominant medical model approach to the technique are exposed. A discussion of reproductive autonomy in light of emerging testing applications of PGD not directly related to the avoidance of serious genetic abnormalities in the resulting child demonstrates the complexity of both clinical decision-making and public policy formulation with regard to PGD. Recently proposed legislation in Canada reflects such complexities, and highlights the lack of social consensus on the appropriate uses of, and restrictions on, PGD. A variety of "soft law" instruments, notably professional codes of practice and research guidelines implemented by institutional ethics committees, may mitigate some of the uncertainty surrounding PGD in Canada, but their limited applicability and espousal of the medical model approach render questionable their capacity to reconcile tolerance of pluralism with respect for human life, diversity, and reproductive autonomy.
13
Lo, Yuk-Ming Dennis. „Genetic analysis of fetal cells in maternal blood“. Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359448.
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14
Jafri, Syed Hussain. „Attitudes toward prenatal diagnosis and termination of pregnancy in Pakistan“. Thesis, University of Leeds, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.713499.
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Introduction: Prenatal diagnosis for genetic conditions has been available in Pakistan since 1994, however very little is known about this population's attitudes toward prenatal diagnosis or termination of affected pregnancies for different conditions. Advances in molecular biology mean it is possible to offer prenatal diagnosis for an increasing number of conditions and therefore, it is important to assess these attitudes. Objective: To explore Pakistani parents' attitudes toward prenatal diagnosis and termination of affected pregnancies for a range of conditions and the factors that contribute towards such attitudes in parents with and without children affected with conditions. Methodology: Attitudes of 400 parents (200 with affected and 200 with unaffected children) towards diagnosis and termination of pregnancy for 30 different genetic conditions were explored, using a UK questionnaire (Hewison et al., 2007). Factors that affect parents' attitudes towards diagnosis and termination of pregnancy for different genetic conditions were also explored through interviews with 40 parents (20 with affected and 20 with unaffected children). Results: Parents held favourable attitudes to prenatal diagnosis and termination of pregnancy for different conditions. Only 3% of parents wanted no prenatal diagnosis and 13.8% did not want termination of pregnancy at all. Mothers and fathers had similar attitudes towards prenatal diagnosis and termination of pregnancy but mothers had higher acceptability of prenatal diagnosis and termination of pregnancy than fathers. Similarly, parents with affected children were more in favour of prenatal diagnosis and termination of pregnancy than parents with unaffected children. The variation in parents' attitudes showed that there was more acceptability for prenatal diagnosis and termination of pregnancy for conditions perceived to be more severe. The most important factors in most parents' decision about termination of pregnancy were suffering of the child and the family, negative attitudes of society, availability of required resources to care for an affected child and and religious beliefs. There was lack of awareness about Islam's stance on termination of pregnancy. The role of family members and health care providers in decision making related to prenatal diagnosis and termination of pregnancy was considered important by some but not all parents. Conclusion: The findings challenged the stereotypes about the non acceptance of termination of pregnancy for genetic conditions in Muslim populations. There is a need to raise awareness of genetic conditions, Islam's stance on termination of pregnancy and availability of screening and prevention services of genetic conditions in Pakistan. The study also highlighted the need for a comprehensive policy on the offer of testing and termination for genetic conditions in Pakistan to ensure easy access to at-risk parents. Furthermore, clinical guidelines should be developed for healthcare providers to facilitate autonomous decision making through the provision of information for parents on testing and termination issues. Technological advances in the field of genetic testing are not only providing more reproductive choices to parents but are also presenting them with more dilemmas.
15
Morrigan, Viviane School of History & Philosophy of Science UNSW. „An ethics of reproductive choice : genetic counselling and prenatal diagnosis“. Awarded by:University of New South Wales. School of History & Philosophy of Science, 2002. http://handle.unsw.edu.au/1959.4/19396.
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For this project I describe the socio-historical development of a particular application of genetic prenatal diagnosis, in terms of changing social relations that govern an ethics of reproductive choice. I examine ways that medicine and government articulate prenatal diagnosis to problematise the maternal body and govern women's reproductive choices about chromosomal abnormality in the fetus. Since its introduction in the early 1970s, the major use of prenatal diagnosis has been to detect chromosomal abnormalities-in particular, Down syndrome-in the fetus. Medico-scientific knowledge claims negotiated in everyday practices in the genetic counselling clinic between health professionals and their clients are situated within broader social relations. Negotiations between medicine and government have produced technoscientific possibilities, realised with greater or lesser success in the co-construction of a workable prenatal diagnosis standardised package. I describe how these socio-technical relations have produced similarities and differences across time, and national and professional boundaries. My analysis draws on observations in three genetic counselling clinics, and of the health professionals' other work activities. I also draw on interviews with them and other actors in that arena, as well as claims made about prenatal diagnosis technologies in the medico-scientific literature. I analyse my data using concepts developed in social worlds/arenas theory within a Foucauldian framework of social relations that govern the body. Since the early formation of a standardised package of genetic counselling about amniocentesis, ethical decisions about prenatal diagnosis have identified multiple parts of the self to be governed. This ethics has relied on a duty to make genetically responsible decisions as a particular way to relate to oneself, although it has been expressed in different ways. Newer technologies have articulated greater ethical possibilities for governing the self by co-constructing new ways of assembling the constituent components. Throughout, there have been tensions between two major aims for governing the self: that of giving birth to a healthy baby, and that of managing maternal rationality in order to act as an autonomous rational individual. I have thus described how a woman's use of prenatal diagnosis is not simply one of individual choice. Her decision is a complex ethical one that is historically and socially contingent on relations between medicine and government that present the maternal body in certain ways for her to act upon herself.
16
Saltvedt, Sissel. „Prenatal diagnosis in routine antenatal care : a randomised controlled trial /“. Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-549-6/.
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17
Cederholm, Maria. „Consequences of amniocentesis and chorionic villus sampling for prenatal diagnosis“. Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2002. http://publications.uu.se/theses/91-554-5225-6/.
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18
Johansen, Marianne. „Trophoblast deportation : its relevance for pre-eclampsia and prenatal diagnosis“. Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337598.
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19
Smith, Marissa B. „A description of genetic counselors' views and current practice with regard to the use of array-CGH for prenatal diagnosis“. Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=case1246977726.
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20
Strange, Heather. „Non-invasive prenatal diagnosis and testing : perspectives on the emergence and translation of a new prenatal testing technology“. Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/90887/.
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This thesis presents findings from a qualitative study of the emergence and early clinical translation of non-invasive prenatal diagnosis (NIPD) in the UK. Drawing from interviews with a range of experts and users I track the enrolment and translation of this new prenatal testing technology across a variety of clinical and social spaces. I show how encounters with NIPD prompt deep critical examination of the moral, social and political implications - not only of the technology - but of the established clinical practices (routine and specialised prenatal testing) and specific policy contexts (prenatal screening programmes) within which NIPD has begun to sediment. I explore how, as NIPD advances at a rapid pace and emerges within a culturally and politically complex context, the technology both aligns with and disrupts routine practices of prenatal screening and diagnosis. I show how, as the technology divides into two major strands - NIPD and NIPT - at an early stage of development, and before becoming naturalised/normalised within the clinic, scientists, clinicians and policy makers attempt to pin down, define and ‘fix’ the technology, drawing upon and engaging in substantive practices of division, categorisation and classification. I explore ambiguities present within such accounts, highlighting dissenting voices and moments of problematisation, and following this, I show how the ‘troubling’ of boundaries prompts much examination of ethical and social concerns. As a location within which interviewees explored more contentious issues, I show how abortion emerged as central to the discussion of NIPD. I proceed to show how institutionalised, professionalised bioethical debate dominates mainstream discourse, and I explain how a particular construction of the informed, individual choice-maker is mobilised in order to locate moral and political responsibility for testing in the hands of individuals, and to distance political/organisational structures from entanglement with problematic concerns. I explore how clinicians and patients respond to this positioning in multiple ways, both assimilating and questioning the mainstream discourse of ‘informed choice’. In conclusion, I highlight the broader (bio)political aspects of NIPD’s emergence and translation within prenatal screening and diagnosis.
21
McCormack, Michael James. „Development of prenatal diagnosis of metabolic disorders using chorionic villus sampling“. Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317449.
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22
Liu, David T. Y. „Development of transcervical chorion villus sampling for first trimester prenatal diagnosis“. Thesis, University of Nottingham, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293186.
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23
Sconyers, Emma (Emma G. ). „I carry you in my heart : facing an incurable prenatal diagnosis“. Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92632.
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Thesis: S.M. in Science Writing, Massachusetts Institute of Technology, Department of Humanities, Graduate Program in Science Writing, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 38-40).
Prenatal diagnosis has given doctors the ability to predict problems before a child is even born. But what happens when the information gleaned from these tests is that the child is fatally sick? Doctors call these "futile" pregnancies. The increasing sophistication and prevalence of prenatal diagnostic tests means that prospective parents and their doctors are grappling with ethical questions unheard of just half a century ago. Legislators try to demarcate what choices are "good" and "bad". However, there is no good choice when it comes to a fatally ill infant. While archival research is used to frame modem perspectives, this thesis aims to explore the different choices women make and the difficulties they must grapple with in this day and age.
by Emma Sconyers.
S.M. in Science Writing
24
Alsulaiman, Ayman. „Attitudes toward prenatal diagnosis and termination of pregnancy in Saudi Arabia“. Thesis, University of Leeds, 2004. http://etheses.whiterose.ac.uk/536/.
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INTRODUCTION: Advances in molecular biology will soon make it possible to offer parents prenatal testing for a large number of different genetic disorders. The tests that have been offered to date are available because of technology, not because of the burden or prevalence of the condition. Parents' attitudes to different genetic disorders need to be evaluated, because little is known about how people's attitudes to testing for one disorder relate to their views on testing for other disorders. AIMS: To assess the attitudes of Saudi parents with and without an affected child, towards prenatal diagnosis and termination of pregnancy for a range of different genetic disorders, and the factors that affect their attitudes. METHODS: The study was conducted using structured questionnaires and semi-structured interviews. 400 Saudi parents with and without affected children completed a structured questionnaire and forty of these were then interviewed. The questionnaires were designed to assess parents' attitudes towards prenatal diagnosis and termination of the pregnancy, for thirty different conditions. The interviews were designed to explore the factors that affect parents' attitudes. FINDINGS: Parents had different attitudes to different conditions. Overall, there was an unexpectedly high level of acceptance of prenatal diagnosis and termination of pregnancy for a range of different conditions in this Muslim sample. It was also found that parents with an affected child held more favourable attitudes towards termination of the pregnancy than parents without an affected child. Fathers without an affected child held the least favourable attitudes towards termination of pregnancy. DISCUSSION: The evidence suggests that parents perceive genetic conditions differently according to their individual experience. Islam is not the main factor that influences Muslim parents toward prenatal diagnosis and termination of the pregnancy. New technologies provide parents with more reproductive choices but also present them with more dilemmas. Further investigation about factors associated with testing and termination choices is recommended.
25
Bridle, Lisa. „Stories of choice : mothers of children with Down syndrome and the ethics of prenatal diagnosis /“. [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18304.pdf.
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Yeoh, S. C. „The isolation and identification of fetal leucocytes in the maternal circulation“. Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.256745.
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Hui, Pui-wah, und 許佩華. „Nuchal translucency in pregnancies conceived after assisted reproduction technology“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31971040.
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28
Hui, Pui-wah, und 許佩華. „Markers of Down syndrome and fetal growth profile in pregnancies conceived with assisted reproduction“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/208518.
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Assisted reproduction technology is increasingly used for treatment of couples with subfertility. These women are usually of more advanced maternal age and carry a higher risk of fetal Down syndrome. Results from early publications showed that biochemical markers for screening of fetal Down syndrome in the second trimester were different between pregnancies from in vitro fertilization (IVF) and natural conception. This could potentially increase the false positive rate and result in unnecessary invasive diagnostic procedures. Questions were raised as to whether the alterations were related to ovarian stimulation. This laid the fundamentals of a series of studies presented in this thesis with an aim to address the variations in the concentrations of markers of fetal Down syndrome and the fetal growth profile of pregnancies conceived following different assisted reproduction treatments.
Studies were conducted on maternal serum and amniotic fluid alpha fetoprotein (AFP) and human chorionic gonadotrophin (hCG) in the second trimester in pregnancies conceived by assisted reproduction. A reduced level of AFP in maternal serum in pregnancies with fresh embryos together with an elevated level of hCG in both maternal serum and amniotic fluid in pregnancies with frozen thawed embryos were found. This pioneer piece of data showing the raised hCG in frozen thawed embryo pregnancies with unstimulated treatment cycles spoke against the ovarian driven hypothesis, but suggested placental dysfunction be a possible underlying pathophysiology.
For markers adopted in the first trimester, the level of pregnancy associated protein A (PAPP-A) was significantly reduced in pregnancies from assisted reproduction. The data on free βhCG was heterogeneous. Apart from biochemical markers, the nuchal translucency was also increased in these singleton pregnancies but not in dichorionic twins. As the direction of deviations of these markers in unaffected pregnancies from assisted reproduction resembled those observed in pregnancies affected by Down syndrome, appropriate adjustment was necessary to reduce the false positive rate for these women.
Altered biochemical markers, notably a low PAPP-A level, were also associated with adverse obstetric outcomes. The changes observed in pregnancies from assisted reproduction might be a manifestation of an intrinsic placental insufficiency or fetal developmental delay. A longitudinal study was performed to examine the intrauterine fetal growth profile in these pregnancies. The rate of increment in the mean sac size, which could represent an adaptive compensatory mechanism, was significantly greater in pregnancies from assisted reproduction compared to natural conception.
We concluded that pregnancies conceived after assisted reproduction technology were different from pregnancies from natural conception in terms of the concentrations of biochemical and ultrasound markers of Down syndrome. Due to the wide variation in treatment protocols and patients’ background demographics, the exact underlying pathophysiology might be difficult to be explored. Couples undergoing assisted reproduction treatment should be counseled on the increased risk of adverse pregnancy course and perinatal outcome.published_or_final_version
Medicine
Master
Doctor of Medicine
29
Ager, R. P. „Studies on some biochemical methods for the prenatal diagnosis of Down's syndrome“. Thesis, University of Salford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381649.
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Elfarawi, Hunaydah. „Alobar Holoprosencephaly: Parental Perspectives on Prenatal Decision-making, Prenatal Provider Prognostication, and Quality of Life“. University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1617108856885634.
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Varawalla, Nermeen Y. „Molecular genetics of beta thalassaemia in Asian Indians : basis for prenatal diagnosis“. Thesis, University of Oxford, 1992. http://ora.ox.ac.uk/objects/uuid:f3a2a0a7-3d14-4dcf-a6fc-616db75119bf.
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The primary aim of this thesis was to outline an approach for the prenatal diagnosis of β-thalassaemia in the Asian Indian population by DNA analysis. A polymerase chain reaction (PCR) based, nonradioactive and rapid technique, allele specific PCR, was successfully developed for the detection of β-thalassaemia mutations. A large sample of 656 unrelated carriers from seven different regions of the Indian subcontinent was studied by allele specific PCR and DNA sequence analysis. Sixteen different β-thalassaemia mutations were identified, two of which were new mutations. Of these five common mutations accounted for 91.7% of β-thalassaemia alleles. The β-globin gene haplotypes of 419 β-Th and 196 β-A chromosomes were constructed. On analysis of which it was inferred that β-thalassaemia mutations occurred relatively recently on existing chromosomal backgrounds and then they experienced positive selection. A strong but not invariant haplotype-mutation linkage was observed. A regional variation in the distribution of β-thalassaemia mutations was found. a-Globin gene mapping studies identifed the single a-globin gene deletion in 24 out of 51 unrelated Asian Indians who were suspected to have a-thalassaemia. It is likely that the remaining carriers have nondeletional a-thalassaemia determinants. To perform preimplantation diagnosis of β-thalassaemia, by analysis of a 10-30 cell embryonic biopsy, a PCR protocol was developed. Using two rounds of PCR with nested primers, successful amplification of a 597 bp fragment of the β-globin gene was achieved from as few as two embryonic cells. The problem of false positive amplification was encountered which appeared to be resolved by UV transillumination of the pre-amplification PCR mix. By allele specific PCR with nested primers it was possible to identify the presence or absence of five β-thalassaemia mutations from 10 pg of template DNA (equivalent to approximately two diploid cells). Thalassaemia control in India is a complex issue; the financial, social and demographic factors involved were considered and recommendations made.
32
Zheng, Yun-Ling. „Rapid prenatal diagnosis of common fetal aneuploidies by fluorescence in situ hybridisation“. Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318418.
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Pinto, Joana Isabel Monteiro. „Metabonomics of the blood of pregnant women for diagnosis of prenatal disorders“. Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/3156.
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Mestrado em Métodos biomolécularesA aplicação da metabonómica na pesquisa de novos biomarcadores de doenças tem ganho um interesse crescente na investigação e desenvolvimento, tanto ao nível do processamento analítico como do tratamento de dados. Nomeadamente, a análise metabonómica usando espectroscopia de Ressonância Magnética Nuclear (NMR) fornece uma grande quantidade de dados de uma forma rápida e não invasiva sobre a composição de amostras complexas como o plasma sanguíneo. Uma vez que as doenças pré-natais têm um elevado impacto no metabolismo materno e fetal, sendo responsáveis por várias complicações durante e depois da gravidez, esta estratégia foi aplicada ao estudo destas doenças através da análise de sangue de senhoras grávidas (colhido entre 15-24 semanas de gestação), com o objectivo de investigar possíveis metabolitos marcadores ou com poder de previsão para a diabetes gestacional e malformações fetais. Num primeiro passo, foram estudados os perfis metabólicos em RMN dos controlos (n=20) e gravidezes com diagnóstico ou suspeita de malformações fetais (n=11) e pré-diabetes gestacional (com posterior diagnóstico clínico entre 22-34 semanas de gestação). A análise multivariada (análise de componentes principais, PCA; análise discriminante pelo método de mínimos quadrados parcias, (PLS-DA) e duas versões deste último, interval PLS-DA e ortogonal PLS-DA (OPLS-DA)) foram aplicados com o objectivo de pesquisar por correlações de solidez estatística entre a composição do plasma e a ocorrência das doenças em estudo. Os resultados mostraram que as amostras controlo e doença podem ser diferenciadas com base no seu perfil metabólico, nomeadamente mostrando níveis mais elevados de compostos que contêm colina em mulheres que desenvolveram diabetes gestacional mais tarde na gravidez. Adicionalmente, níveis mais elevados de piruvato, manose e compostos que contêm colina, e níveis mais baixos de vários aminoácidos e acetato foram encontrados nas gravidezes afectadas por malformações fetais. Numa segunda etapa do trabalho, as mesmas amostras foram analisadas por espectroscopia de Infravermelho com Transformadas de Fourier (FTIR), um método mais barato e acessível para eventual uso clínico. O perfil dos espectros de FTIR também revelou algumas diferenças entre controlos e doenças, no entanto a sua interpretação específica torna-se difícil devido à grande sobreposição de bandas característica de espectros de infravermelho. Estes resultados mostraram que a análise metabonómica de plasma de mulheres grávidas por RMN e FTIR pode ser uma ferramenta poderosa para obter informação bioquímica sobre a saúde pré-natal e encontrar possíveis novos marcadores com potencial para prever doenças, particularmente no caso do diabetes gestacional. ABSTRACT: The use of Metabonomics to search for new disease biomarkers has gained increasing interest in the research community and continuous developments, both at the analytical and data processing levels have boosted this area into new quests in biomarker research. Namely, Nuclear Magnetic Resonance (NMR)-metabonomics provides a large amount of compositional data on complex samples such as blood plasma, in a rapid and non-invasive manner. Since prenatal diseases have a high impact on both maternal and fetal metabolisms, being responsible for a range of complications both during and after pregnancy, this strategy was hereby applied to the study of prenatal diseases, through the analysis of blood (collected at 15-24 gestational weeks), in order to probe for possible marker/predictor metabolites for gestational diabetes and fetal malformations. In the first stage of this work, the plasma metabolic profiles of controls (n=20) and pregnancies affected by diagnosed or suspected fetal malformations (n=11) and pre-gestational diabetes (with posterior clinical diagnosis at 22-34 gestational weeks) were evaluated by NMR spectroscopy. Multivariate analysis (principal component analysis, PCA; partial least squares discriminant analysis, PLS-DA and two extended versions of the latter, interval PLS-DA (iPLS-DA) and orthogonal PLS-DA (OPLS-DA) were applied in order to search for consistent statistical correlations between plasma composition and the occurrence of the diseases. It was found that controls and diseased subjects could be differentiated with basis on their plasma profile, namely showing higher levels of choline-containing compounds in pregestational diabetic women. In addition, higher contents of pyruvate, mannose and choline-containing compounds and lower contents of several amino acids and acetate were found in pregnancies affected by fetal malformations. In a second stage of the work, the same samples were analysed by Fourier Transform Infrared (FTIR) spectroscopy, a cheaper and more-accessible method, more suited to straightforward clinical use. The FTIR spectral profiles also revealed some differences between controls and diseased subjects, the interpretation of which posing a harder challenge than that of NMR. These results have shown that NMR and FTIR metabonomics of pregnant women blood plasma may be a powerful tool to gain insight into prenatal diseases and find possible new markers with potential predictive value, particularly in the case of gestational diabetes.
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Sutton, Erica J. „Prenatal testing and informed choice : the need for improved communication and understanding between health care professionals and pregnant women“. Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19653.
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This research examines the many different ethical issues that emerge in the health care setting with regards to prenatal diagnostic testing. Identifying the areas of clinical practice and religious counselling in need of improvements, particularly physician-client communication, is important to ensure that competent pregnant women make informed, considered choices about prenatal testing. This paper investigates the many factors that contribute to pregnant women's decision-making processes surrounding the acceptance or refusal of the maternal serum alpha-fetoprotein screen, ultrasonography, amniocentesis, chorionic villus sampling, and preimplantation diagnosis. Integrating scholarship in bioethics, religious studies, and the anthropological and sociological study of medicine, this dissertation offers a comparative analysis of religious attitudes toward prenatal diagnostic testing, describes the complexities of practical decision-making by pregnant women faced with genuine ethical dilemmas, and provides an analysis of ethical issues related to prenatal testing. This research will be of interest to scholars in religious studies and bioethics, prenatal genetic counsellors and obstetricians involved in the provision of prenatal diagnostic testing services, and specialists in women's health and reproductive decisionmaking.
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Sullivan, Amanda. „Genetic risk estimation and attendance for counselling among high-risk mothers-to-be“. Thesis, University of Derby, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341401.
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Jiang, Sheng. „Application of nested PCR, whole genome amplification and comparative genomic hybridisation for single cell genetic analysis“. Thesis, University of Glasgow, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366140.
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Chudleigh, Patricia Margaret. „The clinical significance of fetal renal pyelectasis as detected by routine ultrasound screening in the second trimester of pregnancy“. Thesis, King's College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327174.
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Buamah, P. K. „A study of biochemical methods for the prenatal diagnosis of neural tube defects“. Thesis, University of Newcastle Upon Tyne, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370153.
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De, Blasio Miles Jonathon. „Placental restriction and endocrine control of postnatal growth“. Title page, table of contents and abstract only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phd2869.pdf.
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Wong, Hoi-hei Vera, und 王愷曦. „Isolation of human leukocyte antigen G/cytokeratin 7 positive fetal cells from transcervical samples for potential use in prenatal genetic diagnosis“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2015. http://hdl.handle.net/10722/208587.
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There has been an increase in rates of chromosomal abnormalities in newborns as a result of reproductive aging. For the past decades, a lot of effort has been placed on identifying pregnancies at risk of genetic defects. Conventional prenatal genetic diagnosis is achieved by invasive procedures that have been associated with an increased risk of pregnancy loss. This has led the researchers to explore the use of non-/minimally invasive techniques for prenatal diagnosis.
Trophoblasts are known to be shed from regressing chorionic villi into the lower uterine pole of pregnant women during the first trimester. These cells are trapped within cervical mucus, which can be retrieved with a cytobrush. By using human leukocyte antigen G (HLA-G) and cytokeratin-7 (CK7) as trophoblast markers, this study aims to investigate the possibility of isolating individual fetal trophoblast from transcervical samples for genetic diagnosis.
195 healthy pregnant women requesting for legal termination of pregnancy (TOP) were recruited in this study. Transcervical cells were collected from them with the use of a cytobrush before TOP. HLA-G+ or CK7+ cells were then isolated by a combination of mucolytic action, fluorescent immunohistochemistry, and micromanipulation. The origin of these cells was subsequently investigated by either fluorescent in situ hybridization (FISH) or allelic profiling by quantitative fluorescent polymerase chain reaction (QF-PCR) based on chromosome 16, chromosome X, amelogenin gene and sex determining region Y (SRY) gene.
This study first demonstrated the presence of fetal cells in transcervical samples based on the detection of chromosome Y signal by ordinary PCR. Cells expressing HLA-G and CK7 were also identified among transcervical cells. Immunopositive cells were isolated by micromanipulation under fluorescent microscopy. One isolated cell expressing CK7 was shown to inherit paternal allele at a locus on chromosome 16, suggesting the possible fetal origin of this cell. However, this study was still hampered by a number of technical factors. Further optimization of the protocol is required before transcervical trophoblasts can be retrieved in a reliable manner.published_or_final_version
Obstetrics and Gynaecology
Master
Master of Philosophy
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Puszyk, William Matthew. „Epigenetics of cell-free plasma DNA for non-invasive prenatal diagnosis of fetal aneuploidies“. Thesis, University of Warwick, 2008. http://wrap.warwick.ac.uk/1059/.
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Since the discovery of cell-free fetal DNA in the circulation of pregnant women fetal-specific DNA biomarkers for non-invasive prenatal diagnosis of fetal aneuploidy have been sought. A model system assessing the DNA methylation of placental DNA and adult peripheral leukocyte DNA has been developed previously to represent fetal and maternal plasma DNA. To use DNA methylation to detect specific DNA molecules it is desirable that cellfree plasma DNA maintains the methylation profile of its tissue source. Using the imprinted gene GNAS1, a test has been developed to assess, for the first time the relative abundance of methylated and unmethylated DNA circulating in plasma. Methylated and unmethylated DNA sequences were found in equal abundance. If this finding is applicable to all plasma DNA sequences, we conclude that the steadystate concentration of DNA in methylated and unmethylated form is a reliable indicator of its input into the circulation. We have also investigated whether the abundances of different single copy gene sequences in cell-free plasma DNA are equal. Using real-time PCR, the relative abundances of six unique genomic DNA sequences in plasma were assessed. We find that plasma DNA from different sequences is not present in equal abundance in normal healthy individuals. The relative abundance of sequences tested differed by as much as 12.3 fold. We present a panel of novel candidate epigenetic biomarkers which have been identified using the model system. Of 366 DNA regions tested 3% were found to be differential. Further characterisation of these candidate epigenetic biomarkers has revealed limitations of the model system. In view of these results, future epigenetic biomarker development should be achieved by a direct assessment of first trimester plasma DNA.
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Yau, Hoi-ying Alice, und 邱凱盈. „Risk communication in prenatal screening for Down syndrome: a discourse analytic study of patients'risk talk“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48079790.
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Risk is a crucial concept in healthcare communication. This is attested to by a large
body of research on risk communication in psychology, sociology, and, more recently,
discourse analysis. This previous research has primarily focused on how healthcare
providers manage risk talk, whereas patients’ risk talk has received little attention.
Where it has been researched, it has been presented in an oversimplified way, namely
that the patients have been reported to perceive their risk in a simplified,
‘all-or-nothing manner’. Using theme-oriented discourse analysis (Roberts and
Sarangi, 2005), this study challenges this simplified perception by examining patients’
risk talk in prenatal screening for Down syndrome.
The data for this study comprises 14 video-recorded consultations collected in one
prenatal hospital in Hong Kong. The particular focus of the study is on patients who
have received a ‘positive’ result from the initial screening for Down syndrome that
has put them in a high-risk group by increasing their probability of having a baby with
Down syndrome. In these consultations patients are informed about further testing to
confirm the diagnosis. To examine the patients’ risk talk, the transcripts of the
interactions have been coded along the lines of structural, thematic and interactional
maps (Roberts and Sarangi, 2005) to note down risk talk by patients, what is it
concerned with and the interactional dynamics of how it is managed.
The analysis suggests that patients’ risk talk concerns three types of risks, namely the
“risk of occurrence” (that is the probability of having a child with Down Syndrome)
the “risk of knowing” (that is dealing with the knowledge about having a child with
Down Syndrome) and what has been referred to in this study as the “risk of not
knowing” (that is not finding out about the condition due to the uncertainty
surrounding the tests). In contrast to the findings in the previous studies, the patients
in the data actively initiate risk talk by raising clarification questions and talking
about their concerns. The analysis has revealed the differences in how different types
of risk talk are constructed by the patients. These differences are discussed in regards
to the phases of the consultation in which risk talk occurs and whether risk talk is
aimed at eliciting further information or making a decision about pursuing further
testing. The analysis has also noted that risk communication is a joint activity
involving the patients and the healthcare providers. In addressing patients’ risk talk
the healthcare providers in the data take on an indirect approach, thereby avoiding
influencing the patients’ decision-making and managing the uncertainty surrounding
prenatal screening. The analysis has also pointed out that the patients’ socioeconomic
and cultural backgrounds have a crucial impact on how risk talk is constructed by the
patients.published_or_final_version
Linguistics
Master
Master of Philosophy
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Lane, Jonnie A. „Evaluation of maternal serum triple screen as an identifier of trisomy 21 pregnancy“. Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1688.
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Corrochano, Fatule Mariana, Rodriguez Rodolfo Llanos und Alcides Garcia. „Quiste de colédoco en una lactante de tres meses de edad: diagnóstico prenatal y manejo quirúrgico“. Asociación Interciencia, 2014. http://hdl.handle.net/10757/333630.
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El quiste de colédoco es una patología poco común, diagnosticada generalmente después del nacimiento; pero en los
últimos tiempos el diagnóstico prenatal ha tomado mayor importancia, pues permite una intervención precoz y brinda
un mejor pronóstico a los pacientes. Se presenta el caso de una lactante que fue diagnosticada mediante ecografía
obstétrica, a las 21 semanas de vida intrauterina; confirmándose luego el diagnóstico por medio de resonancia
magnética. La paciente fue operada a los tres meses de vida, realizándosele una quistectomía, colecistectomía y
derivación biliodigestiva en Y de Roux, con evolución posoperatoria favorable.
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Emad, Ahmed Anwar Hasanin. „Development and assessment of strategies for non-invasive prenatal diagnosis using fetal cells in maternal blood“. Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5855.
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Abstract : Current prenatal diagnosis depends on invasive procedures and is thus offered only to high-risk pregnancies. Development of non-invasive prenatal diagnosis (NIPD) would change the risk-benefit ratio and make it likely that more women would benefit from prenatal testing. Scientists have documented the presence of rare fetal cells in maternal blood and envisioned targeting them with specific markers and their use in NIPD. Considering their extremely low frequency in maternal blood, fetal cells have been difficult to retrieve and use in clinical practice. Therefore, there is a pressing need for systematic sequential studies to evaluate their feasibility in NIPD.
Generally, detection of rare cells within a large cell population carries great potentialities for the prospects of cancer management and NIPD. Manual scanning is very cumbersome and time-consuming Therefore; the first part of our project was, dedicated to the optimization of an effective strategy to evaluate retrieval of rare cells. We have developed a way of distributing a controlled number of target cells among hundreds of thousands of other cells on microscope slides. This strategy allows the precise evaluation of the retrieval of rare events and the comparizon of the efficacy of different techniques and enrichment approaches by knowing the definite number and locations of target cells on the slides. Furthermore, it allows the evaluation of hybridization of missed events. We have also developed a robust custom-made detection algorithm for rare cells using the MetaSystems automated platform and have used this strategy in the validation of manual and automatic scanning of 60 slides with a pre-defined number of rare male cells among a pure population of female cells using XY-FISH. Consequently, we tested the developed classifier for the detection of real fetal cells from maternal blood in both normal and aneuploid pregnancies with Down syndrome. We further evaluated the number of fetal cells with different methods of enrichments in the first and second trimesters. The data collected confirmed the early presence of fetal cells in all of the pregnancies tested and their frequencies were higher in cases of aneuploidies. Fetal cells are in a state of dynamic change throughout the pregnancy. Higher numbers of these cells can be obtained by optimizing the harvest time and methods of enrichment. We found that automatic scanning is more sensitive and reliable than manual detection. Furthermore, it alleviates the burden of scanning large numbers of cells and thus is more suitable for clinical application. We also demonstrated the feasibility of using rare cells in NIPD. Five microdissected amniotic fetal cells from 26 cases of normal and aneuploid pregnancies were quite enough to provide accurate NIPD through using whole genome amplification coupled with QF-PCR. Our findings laid the ground for the use of rare fetal cells in maternal blood for NIPD. // Résumé : Le diagnostic prénatal résulte encore aujourd’hui de procédures invasives, qui présentent des risques pour la grossesse. Le développement du diagnostic prénatal non-invasif (DPNI) changerait le rapport risque : bénéfice, rendant le diagnostic prénatal plus intéressant pour les femmes enceintes. Plusieurs chercheurs ont montré la présence de cellules fœtales dans le sang maternel et des travaux ont été entrepris afin de les cibler et de les utiliser éventuellement en DPNI. Toutefois, la faible concentration des cellules fœtales dans le sang maternel réduit les possibilités d’isolement ainsi que celles de leur utilisation en clinique. Un autre aspect technique du DPNI, le balayage manuel, est très laborieux, surtout en terme de temps technique. Il y a donc un besoin certain pour des études approfondies afin d’évaluer et d’améliorer la faisabilité du DPNI. La détection d’évènements rares dans une grande population cellulaire offre un potentiel pour le diagnostic en oncologie mais aussi en diagnostic prénatal. Dans cette thèse, la première étude était dédiée à l’optimisation d’une stratégie pour détecter les cellules rares. Nous avons développé une méthode d’étalement sur lame d’un nombre précis de cellules cibles parmi des centaines de milliers de cellules. Cette stratégie a permis d’évaluer le taux de détection d’évènements rares et de comparer l’efficacité des techniques d’enrichissement en connaissant le nombre exact et la localisation de cellules cibles sur les lames. De plus, il a été possible d’évaluer les problèmes d’hybridation des évènements manqués. Nous avons, par la suite, développé un algorithme robuste pour la détection de cellules rares en utilisant la plateforme de microscopie automatisée MetaSystems et utilisé cette approche dans la validation des balayages manuel et automatique d’un nombre précis de cellules mâles parmi une large population de cellules femelles marquées avec la technique FISH. Nous avons testé ce classificateur avec des échantillons de sang de femmes enceintes de grossesses normales et aneuploïdes et évalué la fréquence de cellules fœtales isolées par différentes méthodes d’enrichissement au cours des premier et second trimestres de grossesse. Les données accumulées ont confirmé la présence de cellules fœtales chez toutes les grossesses et leur fréquence plus élevée dans les grossesses aneuploïdes. Le nombre de cellules fœtales est dynamique tout au long de la grossesse. De plus, un nombre plus élevé de cellules fœtales peut être obtenu en optimisant le moment du prélèvement et les méthodes d’enrichissement. De plus, le balayage automatique s’est avéré plus sensible et constant que le balayage manuel, ce qui permet de balayer un grand nombre de cellules et devient plus approprié pour une application clinique. Nous avons aussi montré la faisabilité d’utiliser des cellules fœtales dans le cadre du DPNI. Cinq cellules amniotiques microdisséquées, provenant de grossesses normales et aneuploïdes, ont suffi pour poser un diagnostic prénatal par une combinaison de l’amplification du génome complet et de la technique QF-PCR (réaction quantitative en fluorescence d’amplification entraînée par une polymérase) permettant la détection d’anomalies chromosomiques. Nos résultats ouvrent la voie à l’utilisation de cellules fœtales dans le sang maternel pour le DPNI.
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Rodríguez, Pérez Mª Ángeles. „Valoración ecográfica prenatal del cono medular fetal“. Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/397729.
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Con el término de disrafismos espinales se agrupan una serie heterogénea de malformaciones congénitas de la médula espinal definida por el defecto de la fusión de las estructuras neurales, óseas y mesenquimatosas de la línea media. Los disrafismos cerrados (espectro muy heterogéneo de anomalías: diastematomielia, lipomas, filum terminal engrosado, mielocistoceles, senos dérmicos), son más difíciles de diagnosticar intraútero debido a la ausencia de anomalías intracraneales. Frecuentemente se asocian a médula anclada, por lo que el cono medular (CM) se sitúa a un nivel más bajo de lo esperado, y este signo indirecto podría ayudar al diagnostico prenatal de estos defectos. Sin embargo, existen pocos estudios que traten sobre la metodología para valorar adecuadamente el CM fetal.
La importancia del diagnóstico prenatal de los disrafismos ocultos es que el diagnóstico precoz y tratamiento de estas anomalías mejora el pronóstico en cuanto a índice y severidad de las secuelas.
Las hipótesis del trabajo fueron:
1. La ecografía prenatal detallada de la columna vertebral puede determinar la localización del cono medular e identificar los fetos con un CM a un nivel inadecuadamente bajo.
2. La incorporación de la valoración del CM en la ecografía de rutina permite mejorar el diagnóstico prenatal de los defectos de tubo neural cerrados.
Los objetivos:
1. Describir y determinar cuál es el método más reproducible para valorar el cono medular (CM) fetal mediante ecografía prenatal.
2. Analizar cómo factores maternos (índice de masa corporal) y factores fetales (edad gestacional y estática fetal) influyen en la valoración del CM.
3. Analizar la posibilidad de incorporar la evaluación del CM en la ecografía de rutina .
Con este trabajo hemos querido averiguar si alguno de los métodos descritos para valorar el CM (CM level: nivel vertebral, y CS distance: distancia del CM al sacro) podría tener utilidad en la práctica clínica. Con el primer estudio quisimos evaluar cuál de estos métodos era más reproducible. Encontramos poca reproducibilidad interobservador en la valoración del CM level y alta concordancia interexplorador en la valoración de la CS distance. La principal limitación es que se realizó sobre volúmenes en 3D almacenados. Con el propósito de averiguar la posibilidad de incorporar la valoración del CM en la ecografía de rutina realizamos la segunda parte del trabajo. Se pudo valorar el CM en el 82% de las ecografías de rutina. En los casos en donde se pudo valorar el CM se pudo valorar además la CS distance en el 81% de los casos (66,81% del total). Se encontró una asociación entre la valoración del CM y el IMC y la posición fetal, pero no con la EG. La evaluación de la CS distance se asoció con el IMC y la EG pero no con la posición fetal. Se observó una asociación significativa entre la CS distance y la LF, así como entre la CS distance y la EG.
Las conclusiones del trabajo son las siguientes:
1. El método más reproducible para valorar el CM es la medición de la distancia del cono al sacro (CS distance).
2. Los factores maternos (IMC) y fetales (EG y presentación fetal) influyen en la valoración del CM, siendo factores limitantes en su valoración el IMC elevado, edades gestacionales avanzadas y la presentación de nalgas.
3. La medición de la distancia del cono al sacro (CS distance) puede introducirse en la exploración ecográfica morfológica de rutina.
4. El disponer de curvas de normalidad permitiría seguir con más detalle a fetos y recién nacidos con riesgo de presentar un disrafismo espinal oculto.Subtle skin-covered spinal dysraphism are very difficult to detect in utero due to their lack of intracranial anomalies. They are usually associated to tethered cord and the conus medullaris (CM) is located in a lower level than expected. This could be a clue that could lead us to its prenatal diagnosis. The aims of this study were: 1. To determine the most reproducible method in the sonographic evaluation of the conus medullaris (CM). 2. To analyze the ability to measure the conus-sacrum distance (CS distance), and its relationship with gestational age (GA), body mass index (BMI) and fetal position. 3. To analyze if the evaluation of CM distance could be introduced to routine scans for the assessment of prenatal skin-covered spinal dysraphism. With this study we wanted to evaluated if any of the methods described to evaluate the CM (CM level: vertebral level and CS distance: CM-sacrum distance) could be useful in the clinical practice. With the first study we wanted to evaluate which of these methods was the most reproducible. We found low reliability for CM level and high reliability for CS distance. The second study aims to explore the feasibility of routinely measuring the CS distance in CM assessments. We found that the CM and CS distance could be evaluated in 82 and 81% (66.81% of all cases) of cases respectively The CM assessment was statistically associated with BMI and fetal position but not with GA. We observed a significant association between CS distance and FL and GA. The conclusions of this study are: 1. The most reproducible method to assess CM is the measurement of CS distance. 2. The maternal and fetal factors have an effect on the assessment of the CM. High BMI, advanced GA and breech presentation could be potential factors limiting the feasibility of evaluating the CM. 3. The evaluation of the CS distance can be introduced in the routine scans in the assessment of prenatal skin-covered spinal dysraphism. 4. Normality curves would be useful for the follow up of fetuses and newborns in high risk of prenatal skin-covered spinal dysraphism.
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Smolska, Andriana. „Selective abortion on the basis of prenatal genetic diagnosis: ethical problems faced by the doctor“. Thesis, Linköping University, Centre for Applied Ethics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6683.
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The modern world is facing a revolutionary development in the clinical medicine and biomedical sciences. Due to the different life supporting systems, it is easily possible to keep patients with severe diseases alive. With organ transplantation a lot of people, who would otherwise die can live long and happy lives. In vitro fertilization allows a woman to bear the child that is not genetically related to her. Due to the possibility of contraception, safe abortions and prenatal diagnosis, women and couples can make preferable choices concerning their future child. Such medical developments and improvements have a great impact on our life, and provoke a lot of ethical questions and moral dilemmas.
The aim of this thesis is to answer the question whether prenatal diagnosis can be justified as it mainly leads to the selective abortion, whether and when the fetus counts as a person and whether the prospective parents can perform selective abortion on the basis of fetal disability; and to discuss ethical problems that are experienced by the doctor, who brings the news into the family and what is his/her role in the decision-making process.
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Mamalis, Marios [Verfasser], und R. [Akademischer Betreuer] Axt-Fliedner. „Absent Pulmonary Valve Syndrome: Prenatal Diagnosis, Association and Outcome / Marios Mamalis ; Betreuer: R. Axt-Fliedner“. Marburg : Philipps-Universität Marburg, 2019. http://d-nb.info/1178672042/34.
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Gardner, Patricia Emma. „Antibodies to secretory acetylcholinesterase : their possible role in the prenatal diagnosis of neural tube defects“. Thesis, University of Bath, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277120.
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Swarts, Elfriede. „The outcome of prenatal sonographic diagnosis of fetal talipes in the Cape Town Metro district“. Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/27550.
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Background: Talipes equinovarus, also termed club foot, is a congenital deformity of the ankle joint. Despite its prevalence of approximately 1 per 1000 live births, fetal talipes is relatively poorly studied since the introduction of percutaneous tendo Achilles tenotomies. Objectives: To document the associations, outcomes and prognosis of patients with antenatally diagnosed fetal talipes. The study aims to examine the association between, and prevalence of, fetal talipes and other abnormalities, structural and chromosomal, as well as the outcome in relation to postnatal surgery. The accuracy of prenatal ultrasound in diagnosing fetal talipes is also examined. Methods: A retrospective observational study was made of all cases presenting to the Fetal Medicine Unit between 1 January 2009 and 31 December 2014. All the identified cases were analysed to identify isolated talipes, associated abnormalities, and chromosomal abnormalities. The pregnancy outcomes were determined using the Astraia database as well as maternity records. When the outcome resulted in a live infant, these infants were followed up using the files at the referral hospital to determine the treatment method used and the number requiring surgery. Results: There were 155 cases, all referred to the Fetal Medicine Unit. Antenatal data included 75 who had other structural abnormalities and 75 who had isolated talipes. In five of the cases were no sufficient data could be found. Twenty-five cases were lost to follow-up, and 12 cases had no clubfoot at birth. Only one was labelled as having positional clubfoot. There were 91 live births. Of the cases of talipes with associated abnormalities, 21.19% were live births (excluding ENND). All terminations of pregnancy as well as 90.9% of intrauterine fetal deaths were complex talipes, and 94.52% of the cases of isolated talipes were live births. The most common associated abnormalities were of the central nervous system. Seventeen of the live births were lost to follow-up. Of the cases of isolated talipes, 53.19% had tenotomies and Ponseti treatment. The false positive rate of detecting fetal talipes on ultrasound was 7.74%. Conclusion: The study made it evident that complex talipes is associated with a poor pregnancy outcome defined as pregnancy loss, where isolated talipes is usually associated with a good pregnancy outcome. Ultrasound is a good diagnostic tool when diagnosing talipes antenatally but cannot diagnose the severity of the clubfoot. False negatives were not studied. The introduction of tenotomy can make a difference in the outcome of clubfoot in comparison with previous studies where tenotomies were not performed. Medical professionals need to address the importance of counselling, and a multidisciplinary team should be involved in cases involving prenatal counselling.