953 resultados para HUMAN-REPRODUCTION


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This paper reports the results of the most recent in a series of EHSRE workshops designed to synthesize the current state of the field in Andrology and provide recommendations for future work (ESHRE 1998; 1996). Its focus is on methods for detecting sperm DNA damage and potential application of new knowledge about sperm chromatin organization, vulnerability and repair to improve the diagnosis and treatment of clinical infertility associated with that damage. Equally important is the use and reliability of these tests to identify the extent to which environmental contaminants or pharmaceutical agents may contribute to the incidence of sperm DNA damage and male fertility problems. A working group# under the auspices of ESHRE met in May 2009 to assess the current knowledgebase and suggest future basic and clinical research directions. This document presents a synthesis of the working group’s understanding of the recent literature and collective discussions on the current state of knowledge of sperm chromatin structure and function during fertilization. It highlights the biological, assay and clinical uncertainties that require further research and ends with a series of recommendations.

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STUDY QUESTION Is there an association between high levels of sperm DNA damage and miscarriage?SUMMARY ANSWERMiscarriage rates are positively correlated with sperm DNA damage levels.WHAT IS KNOWN ALREADYMost ejaculates contain a subpopulation of sperm with DNA damage, also referred to as DNA fragmentation, in the form of double or single-strand breaks which have been induced in the DNA prior to or following ejaculation. This DNA damage may be particularly elevated in some subfertile men, hence several studies have examined the link between sperm DNA damage levels and conception and miscarriage rates.STUDY DESIGN, SIZE, DURATIONA systematic review and meta-analysis of studies which examined the effect of sperm DNA damage on miscarriage rates was performed. Searches were conducted on MEDLINE, EMBASE and the Cochrane Library without any language restrictions from database inception to January 2012.PARTICIPANTS/MATERIALS, SETTING, METHODSWe used the terms 'DNA damage' or 'DNA fragmentation' combined with 'miscarriage', 'abortion' or 'pregnancy' to generate a set of relevant citations. Data extraction was performed by two reviewers. Study quality was assessed using the Newcastle-Ottawa Scale. Meta-analysis of relative risks of miscarriage was performed with a random effects model. Subgroup analyses were performed by the type of DNA damage test, whether the sperm examined were prepared or from raw semen and for pregnancies resulting from IVF or ICSI treatment.MAIN RESULTS AND THE ROLE OF CHANCEWe identified 16 cohort studies (2969 couples), 14 of which were prospective. Eight studies used acridine orange-based assays, six the TUNEL assay and two the COMET assay. Meta-analysis showed a significant increase in miscarriage in patients with high DNA damage compared with those with low DNA damage [risk ratio (RR) = 2.16 (1.54, 3.03), P <0.00001)]. A subgroup analysis showed that the miscarriage association is strongest for the TUNEL assay (RR = 3.94 (2.45, 6.32), P <0.00001).LIMITATIONS, REASONS FOR CAUTIONThere is some variation in study characteristics, including the use of different assays and different thresholds for DNA damage and the definition of pregnancy loss.WIDER IMPLICATIONS OF THE FINDINGSThe use of methods which select sperm without DNA damage for use in assisted conception treatment may reduce the risk of miscarriage. This finding indicates that assays detecting DNA damage could be considered in those suffering from recurrent pregnancy loss. Further research is necessary to study the mechanisms of DNA damage and the potential therapeutic effects of antioxidant therapy.STUDY FUNDING/COMPETING INTEREST(S)None.

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Do clinicians manage pregnancies conceived by assisted reproductive technologies (ART) differently from spontaneous pregnancies?

Clinicians decisions about prenatal testing during pregnancy depend, at least partially, on the method of conception.

Research thus far has shown that patients decisions regarding prenatal screening are different in ART pregnancies compared with spontaneous ones, such that ART pregnancies may be considered more valuable or precious than pregnancies conceived without treatment.

In this cross-sectional study, preformed during the year 2011, 163 obstetricians and gynecologists in Israel completed an anonymous online questionnaire.

Clinicians were randomly assigned to read one of two versions of a vignette describing the case of a pregnant woman. The two versions differed only with regard to the method of conception (ART; n 78 versus spontaneous; n 85). Clinicians were asked to provide their recommendations regarding amniocentesis.

The response rate among all clinicians invited to complete the questionnaire was 16.7. Of the 85 clinicians presented with the spontaneous pregnancy scenario, 37 (43.5) recommended amniocentesis. In contrast, of the 78 clinicians presented with the ART pregnancy scenario, only 15 (19.2) recommended the test. Clinicians were 3.2 (95 confidence interval [CI]: 1.66.6) times more likely to recommend amniocentesis for a spontaneous pregnancy than for an ART pregnancy.

The study is limited by a low response rate, the relatively small sample and the hypothetical nature of the decision, as clinician recommendations may have differed in an actual clinical setting.

Our findings show that fertility history and use of ART may affect clinicians recommendations regarding amniocentesis following receipt of screening test results. This raises the question of how subjective factors influence clinicians decisions regarding other aspects of pregnancy management.

There was no funding source to this study. The authors declare no conflicts of interest.

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Macrophage inhibitory cytokine-1 (MIC-1) is a multifunctional cytokine produced in high amounts by placental tissue. Inhibiting trophoblast invasion and suppressing inflammation through inhibition of macrophage activation, MIC-1 is thought to provide pleiotropic functions in the establishment and maintenance of pregnancy. So far, little is known about the decidual cell subsets producing MIC-1 and the effect of this cytokine on dendritic cells (DCs), which are known to play a distinct role in the development of pro-fetal tolerance in pregnancy.

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Relatório de Estágio apresentado à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Ensino do 1.º e 2.º ciclo do Ensino Básico

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In this thesis, I explore how the folk-rock music of Ani DiFranco has influenced the activist commitments, sensibilities, and activities of reproductive rights activists. My interest in the relation of popular music to social movements is informed by the work of Simon Frith (1987, 1996a, 1996b), Rob Rosenthal (2001), and Ann Savage (2003). Frith argues that popular music is an important contributor to personal identity and the ways that listeners see the world. Savage (2003) writes that fans develop a unique relationship with feminist/political music, and Rosenthal (2001) argues that popular music can be an important factor in building social movements. I use these arguments to ask what the influence of Ani DiFranco's music has been for reproductive rights activists who are her fans. I conducted in-depth interviews with ten reproductive rights activists who are fans of Ani DiFranco's music. All ten are women in their twenties and thirties living in Ontario or New York. Each has been listening to DiFranco's music for between two and fifteen years, and has considered herself a reproductive rights activist for between eighteen months and twenty years. I examine these women's narratives of their relationships with Ani DiFranco's music and their activist experience through the interconnected lenses of identity, consciousness, and practice. Listening to Ani DiFranco's music affects the fluid ways these women understand their identities as women, as feminists, and in solidarity with others. I draw on Freire's (1970) understanding of conscientization to consider the role that Ani's music has played in heightening women's awareness about reproductive rights issues. The feeling of solidarity with other (both real and perceived) activist fans gives them more confidence that they can make a difference in overcoming social injustice. They believe that Ani's music encourages productive anger, which in turn fuels their passion to take action to make change. Women use Ani's music deliberately for energy and encouragement in their continued activism, and find that it continues to resonate with their evolving identities as women, feminists, and activists. My study builds on those of Rosenthal (2001) and Savage (2003) by focusing on one artist and activists in one social movement. The characteristics of Ani DiFranco, her fan base, and the reproductive rights movement allow new understanding of the ways that female fans who are members of a female-dominated feminist movement interact with the music of a popular independent female artist.

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"Mémoire présenté à la Faculté des études supérieures en vue de l'obtention du grade de LLM en maîtrise option recherche axe Droit, Biotechnologies et Société"

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Introducción: El embarazo ectópico es la primera causa de mortalidad materna durante el primer trimestre del embarazo, y la realidad sociocultural de nuestro país indica que las mujeres están exponiéndose cada vez más a factores que aumentan el riesgo para embarazo ectópico. Se pretende evaluar la asociación de los factores de riesgo en una institución de cuarto nivel. Metodología: Se realizó un estudio de casos y controles, con un caso por cada dos controles, escogidos por medio de un muestreo aleatorio simple. Resultados: Se incluyó un total de 200 pacientes. Ambas poblaciones fueron comparables. La edad promedio de casos fue 29 años y de los controles 24.6 años; la mayoría estaban casadas o en unión libre. Con respecto a los factores de riesgo con resultados estadísticamente significativos (p 0,000) se encontró que existe un mayor riesgo de embarazo ectópico con edad entre 18-35 años, estrato socioeconómico bajo, presencia de ETS, estar casada, tener periodo intergenésico prolongado, haber tenido cirugías pélvicas previas, no usar anticonceptivos, tener endometriosis y tener antecedente de embarazo ectópico (p=0,000). El factor de riesgo más alto es el antecedente de un embarazo ectópico previo OR 66.2 IC95% 60.4 – 72.0 seguido de tener endometriosis con OR 20.2 IC95% 18.6 – 21.9. (p 0,000). Discusión: Los factores de riesgo para embarazo ectópico en el presente estudio son concordantes con otros descritos en la literatura. Es importante conocer a fondo los datos presentados para mejorar los índices de esta patología a nivel nacional.