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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Ofrivillig barnlöshets påverkan på relationen : En kvalitativ litteraturstudie om påverkan på den heterosexuella relationen med ofrivillig barnlöshet

van Ieperen, Jorinde, Lundvall, Alice January 2024 (has links)
BAKGRUNDEn eventuell infertilitetsproblematik utreds först efter ett års oskyddade samlag med utebliven graviditet. Det som följer är oftast fysiska och psykiska påfrestande behandlingar och situationen har betydande inverkan på parets välbefinnande samt kan skapa ohälsa inom relationen. SYFTESyftet med studien är att belysa hur heterosexuella par upplever att ofrivillig barnlöshet påverkar relationen.METODEn kvalitativ litteraturstudie med induktiv ansats har tillämpats för att undersöka studiens syfte. Sex självbiografier har analyserats manifest och resultatet grundas i upplevelser tagna från författarnas berättelser.RESULTATResultatet indikerar att psykiskt lidande på grund av ofrivillig barnlöshet orsakar konflikter i förhållandet och kan leda till ensamhet, både inom relationen och från omgivningen. Det finns en tydlig brist att stöd och förståelse saknas både från närstående och från sjukvården.SLUTSATSRelationens hälsa påverkas både fysiskt och psykiskt hos de par som drabbas av ofrivillig barnlöshet. För att möjliggöra god hälsa behöver sjuksköterskan vara inkännande om upplevelser och vårda båda parterna som en helhet.
42

DNA METHYLATION DIFFERENCES BETWEEN CHILDREN CONCEIVED IN VITRO AND IN VIVO ARE ASSOCIATED WITH ART PROCEDURES

Song, Sisi January 2013 (has links)
Epidemiological data indicate that children conceived in vitro have a greater relative risk of low birth-weight, major and minor birth defects, and rare disorders involving imprinted genes, suggesting that epigenetic changes may be associated with assisted reproduction. DNA methylation and gene expression differences have been found in cord blood and placenta comparing children conceived in vitro using assisted reproductive technology (ART) and children conceived in vivo. The source of these differences (the effect of ART versus underlying infertility) has never been identified in humans. In order to determine what fraction of the DNA methylation and gene expression difference is attributable to the ART procedure and what fraction is attributable to underlying infertility, quasi-transcriptome-wide DNA methylation profiles were compared between (1) in vitro ART children of mothers who are infertile as a result of a physical impediment to fertilization (tubal blockage) or children conceived with the aid of donor oocytes as a group (tubal and donor egg group), and (2) children of parent(s) who have idiopathic infertility (infertility group). Both groups were compared to children conceived in vivo. Our data suggest strongly that many of the DNA methylation and gene expression differences observed between the in vitro and in vivo conceptions are associated with some aspect of ART procedure, rather than underlying infertility. / Molecular Biology and Genetics
43

Triptorelinazetat 2,1 mg versus Triptorelinazetat 4,12 mg zur ovariellen Suppression im Rahmen der In-vitro-Fertilisation

Heinze, Susanne 13 June 2002 (has links)
Die GnRH-Agonisten-Applikation zur Downregulation vor IvF ist "gold standard", überwiegend im sogenannten langen Protokoll. Die Behandlung soll den vorzeitigen LH-Anstieg mit vorzeitiger Ovulation verhindern. Die unerwünschten Wirkungen sind dosisabhängig und rechtfertigen die Suche nach der optimal niedrigen Dosis des GnRH-Agonisten. Mit dieser Fragestellung wurde eine prospektive randomisierte Dosisfindungsstudie durchgeführt. 200 sterile Frauen zwischen 18 und 38 Jahren erhielten vor der IvF-Behandlung im langen Protokoll die Standarddosis von 4,12 mg Triptorelinazetat-Depot (1 Amp. i.m. = Gruppe B: n = 100) versus 2,1 mg Triptorelinazetat Depot (1/2 Amp. i.m = Gruppe A. n = 100) zur Downregulation. Folgende Parameter wurden bestimmt: E2, LH, Progesteron. Die Behandlungsergebnisse wurden korreliert mittels der Anzahl der gewonnenen Oocyten, der fertilisierten Oocyten, der transferierten Embryonen und der Schwangerschaftsraten pro Embryotransfer. Abgebrochene IvF-Zyklen wurden einzeln analysiert. Bezüglich der Hormonwerte waren beide Gruppen ohne signifikanten Unterschied. In der Gruppe der Patientinnen mit der halbierten Dosis (A) kam es nur in einem Fall zu einer vorzeitigen Luteinisierung, in der Standartdosisgruppe (B) in keinem Fall. Wegen low response wurde in Gruppe A in 5 Fällen die Therapie abgebrochen, versus 3 Fälle in Gruppe B (ns). Ebenfalls vergleichbar war das IvF-outcome, nur die ET-Rate pro begonnener Stimulation zeigte einen signifikanten Unterschied: 88 % (A) versus 96 % (B), p / The GnRH agonist application for the downregulation prior to IVF is 'gold standard', mainly in the so-called long protocol. This should avoid premature ovulations. The dose-dependent, undesired effects justify the search for the optimal low dose of the GnRH agonist. A prospective randomised dose-finding study was carried out in this respect. Among 200 sterile women (18 and 38 years) for the planned IVF and/or IVF / ICSI treatment in the long protocol, n = 100 in group A received 2.1 mg Triptorelinacetate depot (1/2 amp., i.m.) and n = 100 in group B the standard dose of 4.12 mg (1 amp., i.m.) for the downregulation. The hormone values E2, LH, progesterone were determined. The treatment results were compared by means of the number and quality of the oocoytes, the embryo transfers and the pregnancy rates. Cancelled IVF cycles were analysed. With respect to the hormone values, neither of the two groups showed significant differences. A premature luteinization occurred in group A (reduced dose) in only one case; in the standard dose of group B, none occurred. Due to the low response, the therapy was cancelled in 5 cases in group A, in comparison to 3 cases in group B (ns). The IVF outcome showed a comparable result. The only significant difference was the ET rate per started stimulation (p
44

Enastående ensamstående? : Valet att bli solomamma med IVF-teknologi. / Stunningly Single? : The choice to become a solo mother by IVF-technology.

Matsdotter, Madelene January 2012 (has links)
Sveriges Riksdag beslöt våren 2012 att även ensamstående kvinnor ska få tillgång till assisterad befruktning i Sverige. Hittills, och än så länge, har ensamstående kvinnor rest utomlands för att fertilitetsbehandlas. Syftet med denna studie har varit att undersöka hur solomammor (kvinnor som valt att skaffa barn som ensamstående) resonerat och resonerar kring sitt val, samt hur de ser på faderskapsprocessen och den kommande lagändringen. Deltagare söktes via en förenings Internetsajt, där medlemmarna alla är frivilligt ensamstående mammor. Fem solomammor berättade om sina resonemang i semistrukturerade intervjuer. Sedan kategoriserades, kodades och tematiserades materialet, och analyserades med hjälp av symbolisk interaktionism, värderingsförändringar och samhällsutveckling. Resultaten visar bland annat att respondenterna verkligen tänkt igenom sitt beslut att bilda familj som ensamstående förälder. De ser främst ser lagändringen som symboliskt viktig, då deras familjeform i och med denna erkänns av samhället. Respondenterna tror att donatorbrist och åldersgränser i Sverige kommer att medföra att ensamstående kvinnor även fortsättningsvis reser utomlands för assisterad befruktning. De negativa åsikter som kommit fram rör sjukvårdskontakter i Sverige och hur en del ensamstående mammor blivit bemötta av socialtjänsthandläggare. Faderskapsprocessen skulle kunna bli mer rättssäker om tydliga, nationella regler utfärdades även för faderskapsutredningar som rör donatorbarn. / The Swedish Riksdag decided in the spring of 2012 that single women also should have access to assisted reproduction in Sweden. Up until now, and so far, single women have travelled abroad for fertility treatment. The purpose of this study has been to explore how solo mothers (women who have chosen to obtain children as a single parent) reasoned and reason about this choice, and how they view the paternity process and the upcoming legislative changes. Participants were sought through an Internet site for an association where all members are single mothers by choice. Five solo mothers talked about their reasoning in semi-structured interviews. The material was then categorized, coded and thematized, and analyzed by using symbolic interactionism, changes in values and the development of society. The results show that the respondents really thought through their decision to found a family as a single parent. They see the legislative changes mainly as symbolically important, as their form of the family will be recognized by society. They believe that the lack of donors and the age limitations in Sweden will result in that single women continues to travel abroad for assisted reproduction technology. The negative opinions that have emerged during interviews are related to health care contacts in Sweden and how some single mothers have been treated by social service caseworkers. The paternity process could become more legally secure if clear, national regulations were issued also for the paternity process regarding donor children.
45

Environmental factors affecting interferon-τ expression and secretion by in vitro produced bovine blastocysts

Hickman, Cristina Fontes Lindemann January 2010 (has links)
Interferon (IFN)τ is the luteotrophic signal in ruminants and is secreted by bovine blastocysts both in vivo and in vitro. IFNτ secretion is highly variable and its control is only partly understood. Most studies on the effects of environmental factors on IFNτ production have evaluated IFNτ production during the time of embryo elongation and attachment. There is less knowledge of how IFNτ production at the blastocyst stage is modulated. Therefore, the hypothesis of this thesis was that the amounts of IFNτ expressed and/or secreted by bovine blastocysts produced in vitro were modulated by environmental factors. In the first set of experiments, bovine embryos were incubated with a cytokine (granulocyte macrophage colony stimulating factor, GM-CSF). GM-CSF had been shown previously to promote embryo viability in a range of species and to modulate IFNτ secretion by ovine blastocysts and thus was classified as a beneficial environmental factor. Three experiments were conducted to test whether GM-CSF stimulated bovine blastocyst development and IFNτ secretion. Embryos were incubated with a range of different concentrations of GM-CSF (2, 5, 10 and 50 ng mL-1) and at different stages of development (1 to 3 and 1 to 9 days post-insemination). Bovine embryos were unresponsive to GM-CSF in terms of IFNτ secretion, pyruvate oxidation, rate of development, blastocyst yield, morphological quality and apoptotic index, irrespective of timing of exposure and/or concentration of GM-CSF. In the second part of the thesis, bovine blastocysts were exposed to a mild heat treatment (42°C for four h) to determine whether heat stress affected IFNτ expression by bovine blastocysts. A novel multiplex reverse-transcription polymerase chain reaction methodology was validated to detect IFNτ and heat shock protein (HSP)70 mRNA in individual bovine embryos relative to an endogenous gene (YWHAZ) and an exogenous mRNA (α-globin) and results were expressed both in absolute terms and in relation to the endogenous control. Heat treatment upregulated IFNτ mRNA expression, suggesting that detrimental environmental factors may influence IFNτ expression. Heat treatment also caused an increase in HSP70 mRNA expression but did not affect blastocyst morphology, suggesting that the level of stress caused by the heat treatment was great enough to activate the cellular stress response, but mild enough not to cause a change in morphology. In addition, the positive correlation between HSP70 and IFNτ transcript levels and the higher IFNτ expression by embryos which showed signs of degeneration and collapse compared to those which progressed in development suggested that IFNτ expression may be indicative of stress. The relationship between IFNτ expression and secretion in vitro with morphology, pyruvate metabolism, apoptotic index and cell number was inconsistent, suggesting that IFNτ production did not correlate with ‘quality’ (defined as an index of viability). Blastocyst yield, day of blastulation and change in morphology index did account for at least part of the variation in IFNτ production, suggesting that some intrinsic factors may regulate IFNτ secretion. These intrinsic factors, however, did not explain all the variation in IFNτ secretion between blastocysts. Therefore, the amount of IFNτ secreted by bovine blastocysts is modulated by both intrinsic and environmental factors. A model was proposed where different levels of stress affect survivability to different extents, and the ability to respond to mild levels of stress may be indicative of improved survivability.
46

Prevalence vybraných polymorfizmů v genu pro receptor luteinizačního hormonu v české populaci a u pacientek s ovariálním hyperstimulačním syndromem / The prevalence of chosen polymorphisms of luteinizing hormone receptor gene in Czech population and patients with ovarian hyperstimulation syndrome

Chrudimská, Jana January 2013 (has links)
Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic potentially life-threatening complication of assisted reproduction techniques (ART). It is caused by an increased sensitivity of ovaries to gonadotropins administered during the controlled ovarian hyperstimulation (COH). Thus, the degree of ovarian response can be gently tuned by genetic polymorphisms of gonadotropins and their receptors. The aim of this study is to ascertain the prevalence of polymorphisms Asn291Ser (rs1470652), Ser312Asn (rs2293275) and insLQ (insertion of leucine and glutamine, rs58356637) in the luteinizing hormone chorionic gonadotropin receptor (LHCGR) gene in 102 Czech fertile men, 149 fertile women and 58 patients with serious grade of OHSS. Detection of the Asn291Ser and Ser312Asn polymorphisms was performed using TaqMan SNP Genotyping Assays. The insLQ variation was detected by the capillary electrophoresis with fluorescence-labeled primers. This study ascertained the prevalence of studied variants in Czech fertile population. Obtained results are in concordance with the majority of data from other European populations. There is no difference in prevalence between control-men and control-women. No relation to the development of OHSS was disclosed. The number of analyzed samples is too small for haplotype analysis. These...
47

Criopreservação de sêmen de primatas não-humanos / Cryopreservation of non-human primate sperm

Carvalho, Fernanda Maria de 30 June 2016 (has links)
O presente trabalho foi composto de dois estudos distintos. O Estudo I, com um foco conservacionista, teve como objetivo a avaliação e comparação de diferentes métodos de criopreservação de sêmen de bugio-preto (Alouatta caraya). Para tanto, o estudo foi dividido em dois experimentos: Experimento I composto de dois ensaios no primeiro ensaio foram comparados dois diluidores comerciais BotuBOV e Test-yolk buffer (TYB) e no segundo ensaio foram comparados dois métodos de criopreservação de sêmen congelação lenta e vitrificação; Experimento II avaliação dos efeitos da adição de DHA e de Trolox (análogo da vitamina E) ao diluidor para criopreservação de sêmen. O diluidor TYB apresentou melhores resultados quando comparados ao BotuBOV. A congelação lenta apresentou melhores resultados quando comparada à vitrificação. Não houve diferença entre o diluidor controle e os diluidores com Trolox, DHA ou combinação dos dois (DHAT), com exceção da integridade de acrossoma, que foi significativamente menor para o diluidor DHAT. Conclui-se que são necessários mais estudos, com utilização de outras doses de DHA e Trolox, além de outros antioxidantes. O Estudo II, com foco em pesquisa biomédica, teve como objetivo a criopreservação de sêmen de macaco-rhesus (Macaca mulata) e avaliação da qualidade pós-descongelação por meio de fecundação in vitro (FIV). Para tanto, o estudo foi dividido em três experimentos: Experimento I avaliação e comparação de dois métodos de criopreservação de sêmen congelação lenta e vitrificação; Experimento II avaliação e comparação de quatro métodos de preparação do sêmen pós-descongelação lavagem simples (LS), swim-up (SU), separação por gradiente de densidade (SGD) e filtragem em lã de vidro (FLV); Experimento III avaliação da qualidade seminal pós-descongelação por meio de FIV. A congelação lenta apresentou melhores resultados que a vitrificação (p<0,05). LS apresentou os melhores resultados, seguido por SGD e SU, enquanto FLV apresentou os piores resultados. LS e SGD foram utilizados para avaliação da qualidade seminal por meio de FIV, utilizando sêmen fresco como controle. As taxas de fecundação (média±EPM%) para oócitos MI inseminados com sêmen fresco (43.5±16.4) foram significativamente maiores (p<0,05) que LS (2.0±2.0), mas não diferiram de SGD (25.1±14.2). Não houve diferença na taxa de blastocistos (média±EPM%) entre os tratamentos (variação de 0 a 11.9±7.9). As taxas de fecundação para oócitos MII inseminados com sêmen fresco (41.4±3.6) também foram significativamente maiores que SGD e LS (18.4±6.9 e 12.7±7.7, respectivamente), assim como a taxa de blastocistos (64.7±13.6; 4.7±4.7; 30.9±13.8, respectivamente). Conclui-se que, espermatozoides criopreservados foram capazes de fertilizar oócitos e os embriões atingiram o estágio de blastocisto. A SGD selecionou espermatozoides pós-descongelação de melhor qualidade para FIV em macacos-rhesus, quando comparada à LS / This work was divided in two studies. The objective of Study I was to test and compare different cryopreservation methods for sperm from black-and-gold howler monkeys (Alouatta caraya), with a focus on species conservation. The study was divided in two experiments. Experiment I composed of two trials the first trial compared two commercial extenders BotuBOV and Test-yolk buffer (TYB), and the second trial compared two cryopreservation methods slow freezing and vitrification; Experiment II evaluation of the effects of DHA and Trolox (vitamin E analog) as additives to the freezing extender. TYB had better results when compared to BotuBOV. Slow freezing had better results when compared to vitrification. There was no difference between control extender (TYB) and extender containing Trolox, DHA or a combination of both (DHAT), except for acrosome integrity, which was significantly lower for DHAT. In conclusion, more studies are necessary, using other doses of DHA and Trolox, as well as other antioxidants. The objective of Study II was to assess the quality of frozen-thawed sperm from rhesus macaques (Macaca mulatta) by in vitro fertilization (IVF). The study was divided in three experiments. Experiment I evaluation and comparison of two cryopreservation methods slow freezing and vitrification; Experiment II evaluation and comparison of four preparation methods for frozen-thawed sperm simple wash (SW), swim-up (SU), density gradient centrifugation (DGC), and glass wool filtration (GWF); and Experiment III evaluation of frozen-thawed sperm quality by IVF. Slow freezing had better results when compared to vitrification (p<0,05). SW had better results, followed by DGC and SU, while GWF had the worse results. SW and DGC were further evaluated by IVF. Fertilization rates (mean±SEM%) with MI oocytes using fresh sperm were significantly higher (43.5±16.4) than with SW (2.0±2.0) and did not differ from DGC (25.1±14.2). There was no difference in blastocyst rates between treatments (range 0 to 11.9±7.9). Fertilization rates with MII ova were also significantly higher with fresh sperm (41.4±3.6) than DGC and SW (18.4±6.9 and 12.7±7.7, respectively), and more blastocysts developed from MIIs fertilized with fresh sperm (64.7±13.6) than SW and DGC (4.7±4.7 and 30.9±13.8, respectively). In conclusion, frozen-thawed sperm were able to fertilize oocytes and embryos reached the blastocyst stage. DGC yielded better frozen-thawed sperm for IVF in rhesus macaques, when compared with SW
48

Current Views on Creating Families: Adoption, Assisted Reproduction and Family Relationships

Weiss, Allison R January 2003 (has links)
Thesis advisor: Diane Scott-Jones / The purpose of this study was to explore young adults' views on building their future families; methods of having children including adoption, in vitro fertilization (IVF), donor insemination, egg donation, and surrogacy; disclosure of these methods to children; and the importance of children's contact with extended family. The sample consisted of 82 Boston College students, 41 males and 41 females, with a mean age of 20.67 years. Participants completed a questionnaire and an open-ended interview. The majority of the participants expected to have a life-long partner, raise at least one child, and help their children build relationships with extended relatives. Males and females did not differ on most questions; however females reported thinking about their future families more often than did males (p = .01), and females expected to start their families earlier than did males (p = .02). Participants were more open to adoption than to assisted reproduction technology (ART). IVF was the most preferred among the methods of ART (p < .001). Participants reported they would be most likely to disclose information to their child had they used adoption or ART and were the genetic parent. Some participants emphasized the importance of disclose to a child had they used ART and were not the genetic parents; approximately one-fourth of participants affirmed that a child has a right to know. Participants reported it would be easier to answer their children's questions about adoption or ART than to initiate a discussion on these topics with their children (p < .001). The majority of participants reported that it was important to help their children build connections with extended family and they planned to accomplish this through visiting and preserving family traditions. The findings provide insight into young adults' expectations for creating their families. / Thesis (BA) — Boston College, 2003. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Psychology. / Discipline: College Honors Program.
49

Aspectos morfológicos, vasculares e endócrinos de prenhezes produzidas por técnicas de reprodução assistida em bovinos / Morphological, vascular, and endocrine aspects of pregnancies derived of assisted reproduction techniques in bovines

Pinaffi, Fábio Luis Valério 15 December 2016 (has links)
Perdas embrionárias e alterações gestacionais são frequentemente observadas em prenhezes de embriões bovinos manipulados in vitro. Sabe-se que tais anormalidades são resultantes de alterações epigenéticas ocasionadas pela manipulação dos gametas e/ou do embrião durante as técnicas de reprodução assistida (ARTs), com destaque para as técnicas de fecundação in vitro (FIV) e da clonagem por transferência nuclear de células somáticas (SCNT). Tais alterações resultam em distúrbios no desenvolvimento do concepto em algum momento crítico entre a fertilização e o parto, fornecendo bons modelos de estudos sobre a fisiopatologia de perdas embrionárias e dos distúrbios de desenvolvimento. Caracterizam-se como momentos críticos após a transferência do embrião (TE) o desenvolvimento embrionário no útero, o reconhecimento materno da gestação, a placentação e o desenvolvimento da placenta e do feto, os quais tem de ser transpassados sem nenhuma falha, permitindo um desenvolvimento normal do concepto até o termo. Sendo assim, o presente trabalho abordou três fases distintas do amplo período gestacional em prenhezes por ARTs. O Estudo 1 foi realizado durante o período peri-reconhecimento materno da gestação e objetivou descrever a abundância de expressão de genes estimulados pelo interferon tau (ISGs) de células mononucleares do sangue periférico (PBMCs) maternas em gestações oriundas de ARTs no primeiro mês de gestação; o Estudo 2 compreendeu os primeiros 35 dias de gestação e objetivou descrever as mudanças morfológicas e vasculares do complexo útero-concepto-ovário e o estímulo à expressão de ISGs em PBMCs em gestações de conceptos clonados por SCNT com diferentes fenótipos de desenvolvimento, sendo esses denominados gestação anembrionada e CL persistente; e o Estudo 3 foi conduzido durante o período pré-parto e objetivou descrever as alterações na produção de esteroides sexuais e corticosteroides em gestações produzidas por ARTs. Três hipóteses foram testadas: (1) Gestações de conceptos clonados por SCNT apresentam uma baixa e mais tardia estimulação de ISGs em PBMCs maternas quando comparadas com gestações de conceptos produzidos por FIV e IA; (2) O concepto clonado por SCNT apresenta um menor estímulo sobre mudanças morfológicas e vasculares do complexo útero-ovário e ISGs em PBMCs maternas durante os primeiros 35 dias de gestação, quando comparado com conceptos oriundos de IA; e (3) Gestações de embriões oriundos de ARTs apresentam alterações na dinâmica esteroidogênica no pré-parto quando comparados com gestações de IA. No estudo 1 foram coletadas amostras de sangue de gestações produzidas por inseminação artificial (IA), FIV e clonagem por SCNT, nos dias 15, 18, 20, 22, 24, 26, 28 e 31 pós-ovulação e foi realizada mensuração da abundância de transcritos de ISGs (OAS1 e ISG15) em PBMCs maternas. No estudo 2, gestações produzidas por IA e clonagem por SCNT, foram submetidas a escaneamentos ultrassonográficos dos ovários, útero e concepto a cada 3 dias do dia 14 ao 35 (dia 0 = ovulação) e amostras de sangue foram coletadas nos dias 15, 18, 20, 22, 24, 26, 28 e 31 para mensuração da abundância de transcritos de ISGs (OAS1 e ISG15) em PBMCs maternas. No estudo 3, foram coletadas amostras de sangue no último mês em gestações naturais, oriundas de FIV e de clonagem por SCNT para análise hormonal de 10 esteroides utilizando o método de espectrometria de massas multi-hormonal de alta resolução LC-MS/MS. O primeiro estudo mostrou semelhanças na expressão de genes estimulados pelo IFNT em gestações oriundas de ARTs e produzidas por IA. Entretanto, a estimulação nas gestações oriundas de ARTs aparentou ser quatro dias mais prolongada, sugerindo uma maior funcionalidade do trofectoderma em conceptos oriundos de ARTs. O segundo estudo demonstrou um aumento na expressão de ISGs em PBMCs maternas tanto em gestações de conceptos normais quanto em anormais, justificando a manutenção da função luteal mesmo na ausência de detecção do concepto por ultrasonografia. No terceiro estudo, demonstrou-se alterações na esteroidogênese nas gestações de embriões FIV e clonados no último mês de gestação, sendo essas compatíveis com a hiperativação da enzima aromatase durante todo o último mês de gestações oriundas de FIV e hiperativação das enzimas P450C11 e P450C21 trinta dias antes do parto em gestações oriundas de clonagem por SCNT. O presente estudo concluiu que conceptos oriundos de FIV e clonagem por SCNT apresentam um prolongamento no estímulo de ISGs pelo IFNT, conceptos clonados anormalos apresentam estímulo de ISGs, o que justifica a manutenção da função luteal, e, por fim, a cascata esteroidonênica que culmina com o parto apresenta-se alterada em gestações oriundas de FIV e clonagem por SCNT. / Pregnancy losses and gestational abnormalities are frequently observed in pregnancies from in vitro produced embryos in bovines. It is known that these abnormalities are due to epigenetic changes from the manipulation of gametes and/or embryo during the use of assisted reproduction techniques (ARTs), especially for the in vitro fertilization (IFV) and cloning by somatic cells nuclear transfer (SCNT). These changes results in disturbances of conceptus development in any critical stage between the fertilization and parturition, which provides good models for the study of physiopathology of embryo losses and disturbances of development. Critical stages after the embryo transfer (ET) to the uterus are characterized as the maternal recognition of pregnancy, placentation, and fetal-placental development, which needs to be surpassed without failures, in order to develop a normal conceptus until term. Therefore, the present work approached three distinct phases of the wide gestational period in pregnancies from ARTs. The Study 1 was conducted during the maternal peri-recongnition of pregnancy period and aimed to describe the expression of interferon stimulated genes (ISGs) in maternal peripheral blood mononuclear cells (PBMCs) in pregnancies derived of ARTs; the Study 2 comprise the first 35 days of pregnancy and aimed to describe morphological and vascular changes of the complex uterus-ovaries-conceptus, as well as the expression of ISGs in maternal PBMCs in pregnancies of conceptus cloned by SCNT with different phenotypes of development, denominated as anembryonic gestation and persistent CL; the Study 3 was conducted during the pre-partum period and aimed to describe changes in the production of sexual steroids and corticosteroids during the last month of pregnancies derived of ARTs. Three hypothesis were tested: (1) Pregnancies of conceptus cloned by SCNT presented a decrease and delay in the stimulation of ISGs in maternal PBMCs when compared with conceptuses produced by IFV and AI; (2) Stimulus from the conceptus for changes in the morphology and vasculature of the the uterus-ovarian complex, detected by ultrasonography in B and Doppler modes, and the stimulation of ISGs in maternal PBMCs during the first 35 days of pregnancy of conceptus cloned by SCNT are less intense when compared with conceptus derived from AI; and (3) Pregnancies derived of ARTs present changes in the steroidogenic dynamics in the pre-partum, when compared with pregnancies derived from AI. In Study 1 blood samples were collected from pregnancies produced by AI, IVF, and cloning by SCNT, at days 15, 18, 20, 22, 24, 26, 28, and 31 post-ovulation for the measurement of abundance of transcripts of ISGs (OAS1 and ISG15) in maternal PBMCs. In Study 2, pregnancies derived of AI and cloning by SCNT, were submitted to ultrasonographic scans for the evaluation and description of morphological and vascular changes in ovaries, uterus, and conceptus every 3 days from day 14 to 35 (day 0 = ovulation) and blood samples were collected on days 15, 18, 20, 22, 24, 26, 28 e 31 for the measurement of the abundance of transcripts of ISGs (OAS1 and ISG15) in maternal PBMCs. In Study 3, blood samples were collected during the last month of pregnancies naturally conceived, derived of IVF, and cloned by SCNT for the analysis of 10 steroids using the method of mass spectrometry high resolution LC-MS/MS. The first study showed similarities in the ISGs expression stimulation in pregnancies derived of ARTs and AI. However, the stimulation in the ART derived pregnancies was apparently 4 days longer, suggesting a greater placental function in conceptus derived of ARTs. The second study showed an increase in ISG expression in both normal and abnormal conceptus development, which justifies the maintenance of CL in the absence of a conceptus structure detected by ultrasonography. In the third study, was detected changes in the steroidogenesis of pregnancies derived of IFV and cloning by SCNT during the last month of pregnancy, which are compatible with the hyperactivation of the aromatase enzyme during the last month of IFV derived pregnancies, and hyperactivation of the enzymes P450C11 and P450C21 thirty days before parturition in pregnancies derived of cloning by SCNT. The present study concludes that conceptus derived of IFV and cloning by SCNT present a prolonged stimulus of ISGs, cloned conceptus with anomalous development presents a stimulus of ISGs, which justifies the CL function maintenance, and, ultimately, the steroidogenic cascade that culminates with the term is altered in pregnancies derived from IFV and cloning by SCNT.
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Controlled ovarian stimulation and intrauterine insemination vs in vitro fertilisation as the first line treatment for unexplained subfertility : a randomised controlled trial

Nandi, Arupa January 2017 (has links)
Background: This thesis is based on a randomised controlled trial comparing the effectiveness of intrauterine insemination (IUI) plus Controlled Ovarian Hyperstimulation (COH) versus in vitro fertilisation (IVF) as the first line treatment option for couples with unexplained subfertility. Subfertility of a couple is classed as unexplained when they fail to conceive after one year of regular unprotected intercourse and when all the standard investigations for ovulation, tubal patency and semen analysis have been found to be normal. It affects 30-40% of couples. The age-old methods of treating these couples have included the empirical use of clomiphene or gonadotrophins to correct any possible subtle defects in ovulation with or without IUI (to overcome any existing cervical barrier to natural conception) or IVF. However, the best treatment options for these couples have yet to be determined. The matter has been made even more controversial by the issue of NICE (National Institute for Health and Care Excellence) guidelines in the UK that suggest IUI be abandoned completely for these women in favour of IVF after 2 years of expectant management. A systematic review of the available literature comparing IUI + COH versus IVF for unexplained subfertility revealed limited numbers of available studies and high clinical and statistical heterogeneity among them. An online survey was also conducted among fertility specialists to establish the general consensus regarding management of such couples. The results revealed a lack of agreement among fertility specialists with regards to the first line treatment of couples with unexplained subfertility. The mixed 8 response to this survey demonstrated the ongoing dilemma among practitioners, much of which was due to the lack of robust evidence. A randomised controlled trial was then designed to examine the effectiveness of COH with gonadotrophins + IUI versus IVF as the first line approach to the treatment of unexplained subfertility (Figure 1). This was the first UK-based randomised controlled trial comparing these two first-line management options for unexplained subfertility.

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