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1.
Hum Reprod ; 31(7): 1508-14, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27165623

RESUMO

STUDY QUESTION: In couples who have chosen and confirmed the fate of surplus frozen embryos, which factors influence their decision, with a special emphasis on their symbolic representation of the embryo(s)? SUMMARY ANSWER: Embryo representation and gamete donation use significantly influence the fate of surplus cryopreserved embryos. WHAT IS KNOWN ALREADY: Previous studies report difficulties for couples to decide whether or not to continue storing their frozen embryo(s) and different factors have been already highlighted which influence their decision, including embryo conceptualization, information and support provided by the medical institution, quality of embryo(s) and life events. Little is known, however, about couples who definitely decided to stop their parental project and finalized the process of decision-making about the fate of their cryopreserved embryo(s). STUDY DESIGN, SIZE, DURATION: This prospective study was conducted over a period of 3 years (2007-2010) and included IVF/ICSI patients with surplus frozen embryos, who made a final embryo disposition decision. Among the 280 eligible IVF/ICSI patients, 247 agreed to participate in the study. According to the available options, 91 persons chose to 'stop cryopreservation', 77 chose donation to 'research' and 48 'embryo donation' to infertile couples. Furthermore, 31 participants who chose embryo donation for a parental project were refused by the center as not compatible with their mandatory medical conditions. Among them, 27 participants then selected donation to research as a new option and were included in a fourth group: 'donation to research after Refusal of Embryo Donation for parental project' or 'research-RED' (n = 27). Four participants chose 'stop cryopreservation', however, given the small number of subjects this latter group was not included in the analysis. In all, 243 participants who made a final choice concerning the fate of their cryopreserved embryos were included in this study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were sent a letter of invitation to a semi-structured interview of 30 min with a psychologist. Interviews were conducted separately for each partner, including a questionnaire with a common part and a specific part, according to the chosen option, and allowing a quantitative evaluation. A multivariate logistic regression model was used to assess the link between their embryo representation and their decision about their embryos' fate. MAIN RESULTS AND THE ROLE OF CHANCE: After adjustment for age, gender, gamete donation, number of children and the different embryo representations, a choice to 'stop cryopreservation' is more frequent if the embryo is represented as a child [odds ratio (OR) adjusted = 3.29, 95% confidence interval (CI) = 1.62-6.66], P = 0.0009. Representing the embryo as a project prompts patients to choose 'donation to research' [OR adjusted = 3.76, 95% CI = 1.56-9.06], P = 0.0032. Respondents are more likely to choose 'embryo donation' if they represent the embryo as a potential person [OR adjusted = 3.77, 95% CI = 1.45-9.80], P = 0.0064. Furthermore, patients who benefited from gamete donation are ∼10 times more likely to donate their embryos to another couple [OR adjusted = 10.62, 95% CI = 3.99-28.30], P < 0.0001. For more than half the participants (57%) the decision-making was easy, however, deciding to stop cryopreservation was significantly more difficult than choosing research or embryo donation (P < 0.0001). LIMITATIONS, REASONS FOR CAUTION: Socio-economic status, moral and religious affiliations are known to influence the choice of couples but analyzing these factors was not an aim of the present study. WIDER IMPLICATIONS OF THE FINDINGS: When couples definitely decide to stop their parental project, the embryo symbolic representation remains the main factor that influences the fate of their frozen embryo(s). Moreover, this representation can evolve when influenced by external events and information provided. In order to support patients who are making this difficult decision, it could be helpful to explore this symbolic representation early in the IVF/ICSI procedure, before surplus embryo freezing, as a new tool enhancing the accuracy of counseling. STUDY FUNDING/COMPETING INTERESTS: this study was supported by a grant from the 'Agence de la biomedicine (ABM)', the national regulatory ART agency, under the authority of the French Ministry of Health. The authors have no conflict of interest to declare.


Assuntos
Destinação do Embrião/estatística & dados numéricos , Adulto , Comportamento de Escolha , Tomada de Decisões , Destinação do Embrião/psicologia , Pesquisas com Embriões , Feminino , Humanos , Estudos Prospectivos , Técnicas de Reprodução Assistida/psicologia
2.
Gynecol Obstet Fertil ; 41(9): 554-7, 2013 Sep.
Artigo em Francês | MEDLINE | ID: mdl-23962680

RESUMO

Frozen thawed embryo transfer is currently an important part of present-day assisted reproductive technology (ART) aiming at increasing the clinical pregnancy rate per oocyte retrieval. Although slow freezing method has been the reference during 2 decades, the recent years witnessed an expansion of ultrarapid cryopreservation method named vitrification. Recently in France, vitrification has been authorized for cryopreserving human embryos. Therefore BLEFCO consortium decides to perform a descriptive study through questionnaires to evaluate the state of vitrification in the French clinical practice. Questionnaires were addressed to the 105 French centres of reproductive biology and 60 were fully completed. Data analysis revealed that embryo survival rate as well as, clinical pregnancy rate were increased after vitrification technology when compared to slow freezing procedure. Overall, these preliminary data suggest that vitrification may improve ART outcomes through an increasing of the cumulative pregnancy rate per oocyte retrieval.


Assuntos
Criopreservação/métodos , Embrião de Mamíferos , Blastocisto/fisiologia , Transferência Embrionária , Feminino , França , Humanos , Gravidez , Taxa de Gravidez , Técnicas de Reprodução Assistida , Inquéritos e Questionários , Resultado do Tratamento
3.
Reprod Biomed Online ; 22(3): 277-83, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21269879

RESUMO

Hypogonadotrophic hypogonadism (HH) is characterized by deficient gonadotrophin secretion, resulting from pituitary or hypothalamic defects. In order to induce spermatogenesis, HH patients are treated with commercially available gonadotrophins. As far as is known, quality and genetic integrity of induced sperm cells have never been investigated, although they represent an important issue, since the ultimate goal of this treatment is to have competent spermatozoa in order to achieve paternity. In order to evaluate the nuclear integrity of induced sperm cells, sperm samples from treated HH patients were compared with sperm samples from normospermic control donors. Sperm cells were analysed by fluorescence in-situ hybridization, using probes specific for chromosomes 13, 21, 18, X and Y, and by TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling assay. Results showed that the rate of aneuploid and diploid sperm cells in patients was not statistically different from controls and that the rate of sperm cells with fragmented DNA was within the normal values. Spermatozoa obtained by gonadotrophin treatment in HH patients are likely to have a balanced chromosomal content and a normal DNA integrity but this conclusion needs to be confirmed by further studies dealing with a greater number of patients.


Assuntos
Cromossomos Humanos/ultraestrutura , Gonadotropinas/farmacologia , Hipogonadismo/tratamento farmacológico , Análise do Sêmen/estatística & dados numéricos , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Gonadotropinas/uso terapêutico , Humanos , Hibridização in Situ Fluorescente , Marcação In Situ das Extremidades Cortadas , Masculino , Razão de Masculinidade
4.
Hum Reprod ; 26(3): 724-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21227944

RESUMO

DAX1/NR0B1 mutations are responsible for X-linked congenital adrenal hypoplasia (AHC) associated with hypogonadotropic hypogonadism (HH). Few data are available concerning testicular function and fertility in men with DAX1 mutations. Azoospermia as well as failure of gonadotrophin treatment have been reported. We induced spermatogenesis in a patient who has a DAX1 mutation (c.1210C>T), leading to a stop codon in position 404 (p.Gln404X). His endocrine testing revealed a low testosterone level at 1.2 nmol/l (N: 12-40) with low FSH and LH levels at 2.1 IU/l (N: 1-5 IU/l) and 0.1 IU/l (N: 1-4 IU/l), respectively. Baseline semen analysis revealed azoospermia. Menotropin (Menopur(®):150 IU, three times weekly) and human chorionic gonadotrophin (1500 IU, twice weekly) were used. After 20 months of treatment, as azoospermia persisted, bilateral multiple site testicular biopsies were performed. Histology revealed severe hypospermatogenesis. Rare spermatozoa were extracted from the right posterior fragment and ICSI was performed. Four embryos were obtained and, after a frozen-thawed single-embryo transfer, the patient's wife became pregnant and gave birth to a healthy boy. We report the first case of paternity after TESE-ICSI in a patient with DAX1 mutation, giving potential hope to these patients to father non-affected children. Furthermore, this case illustrates the fact that patients with X-linked AHC have a primary testicular defect in addition to HH.


Assuntos
Receptor Nuclear Órfão DAX-1/genética , Hipogonadismo/genética , Infertilidade Masculina/genética , Infertilidade Masculina/terapia , Técnicas de Reprodução Assistida , Hiperplasia Suprarrenal Congênita/genética , Hiperplasia Suprarrenal Congênita/patologia , Hiperplasia Suprarrenal Congênita/fisiopatologia , Hiperplasia Suprarrenal Congênita/terapia , Insuficiência Adrenal , Adulto , Receptor Nuclear Órfão DAX-1/química , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Doenças Genéticas Ligadas ao Cromossomo X/fisiopatologia , Doenças Genéticas Ligadas ao Cromossomo X/terapia , Humanos , Hipoadrenocorticismo Familiar , Infertilidade Masculina/tratamento farmacológico , Masculino , Túbulos Seminíferos/citologia , Túbulos Seminíferos/patologia , Espermatogênese/efeitos dos fármacos , Resultado do Tratamento
5.
Gynecol Obstet Fertil ; 37(10): 796-802, 2009 Oct.
Artigo em Francês | MEDLINE | ID: mdl-19766037

RESUMO

OBJECTIVE: Despite normal sperm parameters, 5% of in vitro fertilization (IVF) attempts result in an unpredictable failure of fertilization. In 56% of the cases, there is no obvious oocyte anomaly, but lack of sperm binding to the zona pellucida. This study aims to contribute to clarify the male molecular causes of failures in IVF, which are undetected by classical sperm analysis. PATIENTS AND METHODS: The spermatic proteomic profiles of patients, with a complete failure of fertilization and no spermatozoa bound to the zona pellucida, is compared to controls (patients with normal fertilization and cleavage rates after a classical IVF for tubal indication). All samples are analysed by 2 Dimensional Electrophoresis-Differential In Gel Electrophoresis (2DE-DIGE) after being divided into three fractions according to their isoelectric point (acid, intermediate and basic). RESULTS: Fourteen proteins differentially expressed between all the cases and all the controls were highlighted. Twelve of these proteins were identified by mass spectrometry (six from the acid fraction and six from the basic fraction). Two of these proteins may have an interest in gametic interaction: the laminin receptor LR67 and the L-xylulose reductase. DISCUSSION AND CONCLUSION: More investigation is needed to understand the involvement of the identified proteins in the IVF fertilization failure of the infertile patients in this study.


Assuntos
Fertilização in vitro , Espermatozoides/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Espectrometria de Massas , Proteômica , Receptores de Laminina/metabolismo , Desidrogenase do Álcool de Açúcar/metabolismo , Falha de Tratamento
6.
Gynecol Obstet Fertil ; 37(9): 712-9, 2009 Sep.
Artigo em Francês | MEDLINE | ID: mdl-19682941

RESUMO

Performance and security questions in human oocyte cryopreservation have been taking researchers for about two decades. Oocytes are usually frozen at metaphase II. Immature oocytes cryopreservation is still a research alternative. Two techniques are currently available for oocyte cryopreservation: slow freezing and vitrification. Experimental data suggest that vitrification has less impact on oocyte physiology than classical slow freezing. After slow freezing of mature oocytes, survival and fertilization rates reach 70 to 80% whereas cleavage rates are around 90%, leading to five implantations and 1.2 births per 100 thawed oocytes. After vitrification of mature oocytes, survival and cleavage rates reach 90% leading to 11 implantations and 1.8 births per 100 thawed oocytes. The obstetrical and neonatal prognosis of these pregnancies is reassuring. No increased risk of congenital anomalies has been observed. However, further evaluation is needed to guarantee the safety of cryopreservation procedures. Immature oocyte cryopreservation is not currently perfected but some indications appear of great interest.


Assuntos
Criopreservação/métodos , Oócitos/fisiologia , Sobrevivência Celular , Feminino , Humanos , Metáfase , Oócitos/citologia , Técnicas de Reprodução Assistida
7.
Gynecol Obstet Fertil ; 37(3): 252-6, 2009 Mar.
Artigo em Francês | MEDLINE | ID: mdl-19251450

RESUMO

Preimplantation genetic screening (PGS) of in vitro fertilization (IVF) embryos has been used for advanced maternal age, repeated miscarriages and repeated implantation failure indications. Several non-randomized studies have been published, showing increased implantation rates, decreased miscarriages and trisomy rates. So PGS seemed to improve prognosis for this particular population. In 2004, a prospective randomized study tempered those results, being unable to demonstrate any significant difference of live birth rate with and without PGS in case of advanced maternal age. In July 2007, another multicenter randomized double-blind trial definitely reopened the controversy, reporting that PGS did not increase but instead significantly reduced pregnancy and live birth rates after IVF in women 35 years of age or older. The debate about efficiency and usefulness of PGS is ongoing and other powered randomized studies will be needed to conclude about real PGS usefulness.


Assuntos
Diagnóstico Pré-Implantação , Aborto Habitual , Implantação do Embrião , Feminino , Fertilização in vitro , Humanos , Idade Materna , Gravidez , Taxa de Gravidez , Diagnóstico Pré-Implantação/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
8.
Kidney Int ; 74(1): 37-46, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18368027

RESUMO

Macrophages and dendritic cells are heterogenous and highly plastic bone marrow-derived cells that play major roles in renal diseases. We characterized these cells using immunohistochemistry in 55 renal biopsies from control patients or patients with glomerulonephritis as an initial step towards postulating specific roles for these cells in kidney disease. In proliferative glomerulonephritis numerous CD68 positive (pan monocyte, macrophage and dendritic marker) cells were found in both glomeruli and the tubulointerstitial space, however, a myeloid dendritic cell marker (DC-SIGN) was identified only in the tubulointerstitium. A significant number of plasmacytoid dendritic cells (identified as BDCA-2 positive cells) were seen at sites of interstitial inflammation, including follicular aggregates of inflammatory cells. Langerin positive cells (a marker of Langerhans' cells) were detectable but rare. The area of either CD68 or DC-SIGN positive interstitial cells correlated with serum creatinine. Low levels of DC-SIGN, DC-LAMP and MHC class II mRNA were present in the tubulointerstitial space in controls and increased only in that region in proliferative glomerulonephritis. We demonstrate that the CD68 positive cells infiltrating the glomerulus lack dendritic cell markers (reflecting macrophages), whereas in the tubulointerstitial space the majority of CD68 positive cells are also DC-SIGN positive (reflecting myeloid dendritic cells). Their number correlated with serum creatinine, which further emphasizes the significance of interstitial DCs in progressive glomerular diseases.


Assuntos
Células Dendríticas/imunologia , Glomerulonefrite/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Biomarcadores/análise , Estudos de Casos e Controles , Moléculas de Adesão Celular , Movimento Celular , Progressão da Doença , Glomerulonefrite/patologia , Humanos , Imuno-Histoquímica , Imunofenotipagem , Inflamação , Glomérulos Renais/patologia , Lectinas Tipo C , Pessoa de Meia-Idade , Receptores de Superfície Celular
9.
Mol Hum Reprod ; 13(7): 461-4, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17494104

RESUMO

In elongating spermatids, human sperm chromatin undergoes a complex compaction in which the transition proteins are extensively replaced by the protamine proteins. Several human studies demonstrate that expression of the protamine proteins is altered in some men with male infertility. For this study, we screened the PRM1 (protamine 1) gene for mutations in a large cohort of 281 men seeking infertility treatment. We identified the c.102G>T transversion that results in an p.Arg34Ser amino acid change in two men. One of these patients presented with oligozoospermia associated with increased sperm DNA fragmentation. The second individual was normospermic but together with his partner sought treatment for idiopathic couple infertility. We also identified a novel missense mutation (c.119G>A, p.Cys40Tyr) in a man with oligoasthenozoospermia. These mutations were not observed in control populations. Interestingly, we also detected variants both 5' and 3' to the PRM1 open-reading frame specifically in infertile individuals. Four individuals with unexplained severe oligozoospermia were heterozygote for a c.-107G>C change that is located at -15 bp from the transcription initiation site of the gene. This mutation may influence PRM1 expression. In addition, a c.*51G>C variant was detected in the 3'UTR of PRM1 specifically in a man with severe oligoasthenozoospermia.


Assuntos
Infertilidade Masculina/genética , Protaminas/genética , Sequência de Bases , Análise Mutacional de DNA , Heterozigoto , Humanos , Masculino , Dados de Sequência Molecular , Mutação de Sentido Incorreto
11.
Mol Hum Reprod ; 13(1): 55-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17077110

RESUMO

No phenotypic effect is observed in most inversion heterozygotes. However, reproductive risks may occur in the form of infertility, spontaneous abortions or chromosomally unbalanced children as a consequence of meiotic recombination between inverted and non-inverted chromosomes. An odd number of crossovers within the inverted segment results in gametes bearing recombinant chromosomes with a duplication of the region outside of the inversion segment of one arm and a deletion of the terminal segment of the other arm [dup(p)/del(q) and del(p)/dup(q)]. Using fluorescence in-situ hybridization (FISH), the chromosome segregation of a pericentric inversion of chromosome 1 was studied in spermatozoa of a inv(1)(p22q42) heterozygous carrier. Three-colour FISH was performed on sperm samples using a probe mixture consisting of chromosome 1p telomere-specific probe, chromosome 1q telomere-specific probe and chromosome 18 centromere-specific alpha satellite DNA probe. The frequency of the non-recombinant product was 80.1%. The frequencies of the two types of recombinants carrying a duplication of the short arm and a deletion of the long arm, and vice versa, were respectively 7.6 and 7.2%, and these frequencies were not statistically significant from the expected ratio of 1:1. Sperm-FISH allows the further understanding of segregation patterns and their effect on reproductive failure and allows an accurate genetic counselling.


Assuntos
Inversão Cromossômica , Cromossomos Humanos Par 1 , Hibridização in Situ Fluorescente/métodos , Infertilidade Masculina/genética , Espermatozoides/patologia , Adulto , Humanos , Infertilidade Masculina/patologia , Masculino , Modelos Genéticos , Recombinação Genética
12.
J Gynecol Obstet Biol Reprod (Paris) ; 35(5 Pt 2): 2S47-2S48, 2006 Sep.
Artigo em Francês | MEDLINE | ID: mdl-17057625

RESUMO

Defining markers that could reliably predict good oocyte quality could improve the management of infertile patients. Although a few potentially important predictors of oocyte quality have been identified, their application in assisted reproductive technologies (ART) is discussed.


Assuntos
Oócitos/fisiologia , Ovário/fisiologia , Indução da Ovulação , Biomarcadores , Estradiol/sangue , Feminino , Humanos , Hormônio Luteinizante/sangue , Progesterona/sangue , Técnicas de Reprodução Assistida
13.
Mol Hum Reprod ; 12(10): 643-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16888075

RESUMO

Recently, mutations in the X-linked ubiquitin protease 26 (USP26) gene have been proposed to be associated with male infertility. In particular a 371insACA, 494T>C and 1423C>T haplotype, which results in a T123-124ins, L165S and H475Y amino acid change respectively, has been reported to be associated with Sertoli cell-only syndrome (SCOS) and an absence of sperm in the ejaculate. Here, we demonstrate that two of these changes actually correspond to the ancestral sequence of the gene and that the USP26 haplotype is present in significant frequencies in sub-Saharan African and South and East Asian populations, including in individuals with known fertility. This indicates that the allele is not associated with infertility. The pattern of frequency distribution of the derived haplotype (371delACA, 494T), which is present at high frequencies in most non-African populations could be interpreted as either a result of migration followed by simple genetic drift or alternatively as positive selection acting on the derived alleles. The latter hypothesis seems likely, because there is evidence of strong positive selection acting on the USP26 gene.


Assuntos
Cisteína Endopeptidases/genética , Fertilidade/genética , Haplótipos , Mutação , Testículo/enzimologia , África Subsaariana , Sudeste Asiático , Evolução Molecular , Frequência do Gene , Deriva Genética , Genética Populacional , Humanos , Infertilidade Masculina/genética , Masculino
15.
Hum Reprod ; 19(10): 2325-33, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15284215

RESUMO

BACKGROUND: Assisted hatching (AH) techniques, designed for facilitating the embryo escape out of the zona pellucida (ZP) have been used in IVF centres since 1992. The initial indications for AH were patient's age, ZP thickness, high basal FSH and repeated IVF failures. Several retrospective and prospective studies assessing AH in these indications have given disparate results. Our aims were to evaluate the benefits of AH and immunosuppressive/antibiotic treatment (IA) in patients with either a poor prognosis of success, previous implantation failures or transfers of cryopreserved embryos. METHODS: Four IVF centres allocated 426 patients, randomized for AH and IA, into four groups of AH indications between 1997 and 1999. AH was performed with a diode laser. ZP thickness, opening size and embryo score were recorded. Outcome measures were implantation and delivery rates. RESULTS: Patients coming for a first or third transfer of cryopreserved embryos and poor prognosis patients admitted for a first trial did not benefit from AH. Even patients with repeated implantation failures of fresh embryos did not gain significantly from AH. CONCLUSIONS: Among AH indications, absence of implantation after several transfers of good quality embryos remains the strongest patient selection criterion. Prescription of an immunosuppressive/antibiotic treatment is essential.


Assuntos
Antibacterianos/uso terapêutico , Fertilização in vitro , Imunossupressores/uso terapêutico , Terapia a Laser , Zona Pelúcida/efeitos da radiação , Adulto , Método Duplo-Cego , Quimioterapia Combinada , Implantação do Embrião , Feminino , Humanos , Prontuários Médicos , Seleção de Pacientes , Gravidez , Taxa de Gravidez , Prognóstico , Retratamento , Falha de Tratamento
16.
Eur J Obstet Gynecol Reprod Biol ; 113 Suppl 1: S17-23, 2004 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-15041125

RESUMO

The microtubular meiotic spindle of most mammals, including humans, is very sensitive to cooling [Hum. Reprod. 16 (2001) 2374; Fertil. Steril. 54 (1990) 102; Fertil. Steril. 75 (2001) 769; Zygote 3 (1995) 357] and is rapidly depolymerised even after a slight reduction in temperature to 33 degrees C. Spindle disassembly is dependent on the extent of temperature decrease and its duration. After rewarming, the recovery is far from complete. Cryoprotectants themselves may alter the spindle structure, depending on the duration and temperature of exposure, the duration of recovery at 37 degrees C and the species [Hum. Reprod. Update 2 (1996) 193]. Damage to the meiotic spindle is considered to be the cause of aneuploid embryos, by inducing chromatid non-disjunction and chromosome scattering and by disturbing the sequence of events leading to the completion of meiosis and fertilisation. Nevertheless, a consensus arose from all the studies: appropriate exposure to cryoprotectants and appropriate rates of cooling and thawing allow the cryopreservation of mature oocytes without any significant changes in their second meiotic spindle organisation and without any increase in the rate of aneuploid embryos [Mol. Hum. Reprod. 2 (1996) 445; Hum. Reprod. 8 (1993) 1101; Hum. Reprod. 9 (1994) 684; Microsc. Res. Technol. 27 (1994) 165; Fertil. Steril. 75 (2001) 354]. These fundamental studies in humans, showing good preservation of cell structures after freeze-thaw procedures opened the way to new successful clinical trials with embryos derived from cryopreserved mature oocytes [Fertil. Steril. 68 (1997) 724]. Considering immature oocyte freezing at prophase I (germinal vesicle (GV) stage), a stage which was thought to be less sensitive to cryoinjury, pooled data from the literature showed no advantage in terms of survival rates, fertilisation rates of in vitro matured oocytes and developmental ability of the resulting embryos, especially in unstimulated cycles. Moreover, conflicting results are reported on the effects of freezing on the spindle-chromosome configuration of immature oocytes or in vitro matured oocytes, highlighting the need for large scale studies [Hum. Reprod. 10 (1995) 1816; Hum. Reprod. 13 (Suppl. 3) (1998) 161; Hum. Reprod. 17 (2002) 1885; Microsc. Res. Technol. 27 (1994) 165; Fertil. Steril. 68 (1997) 920]. One child has been born after the use of cryopreserved immature oocytes at GV stage, matured in vitro and fertilised by ICSI [Hum. Reprod. 13 (1998) 3156], demonstrating at least the feasibility of this technique. Improvements are required so as to make mature and immature oocyte cryopreservation an established and safe technique for ART.


Assuntos
Temperatura Baixa , Criopreservação/métodos , Metáfase/fisiologia , Oócitos/fisiologia , Feminino , Temperatura Alta , Humanos , Meiose/fisiologia , Microscopia Confocal
17.
J Health Soc Behav ; 42(3): 235-57, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11668772

RESUMO

The social discovery of Gulf War-related illnesses, like other occupational and environmental disease, is firmly rooted in ongoing disputes over causation. Pressure from veterans groups, as well as intra-governmental disputes, have driven innovative research directions and challenged the dominant epidemiological paradigm. This dominant epidemiological paradigm was originally a position that viewed stress as the primary causal factor. In the emerging dominant epidemiological paradigm, researchers view veterans' symptoms as similar to other multi-symptom diseases and conditions, but with a firmer respect for the reality of those symptoms. In addition, some researchers pursue interactions between stress and physical exposure. We examine the evolution of the DEP to demonstrate that in many disease disputes, an affected population challenges government and science decision-making, and even ways of knowing, in an attempt to negotiate a disease definition and etiology that results in better treatment and prevention. After considerable research effort, only limited evidence has been found for environmental causation, and even many researchers sympathetic to veterans are doubtful that much more will be found. We analyze the social discovery and ongoing contestation of these illnesses, and the consequent effects on health and public policy. For extension to other disease disputes, we provide an overall model of disease discovery and contestation, examining the key forces of government, science, and citizens.


Assuntos
Política de Saúde , Síndrome do Golfo Pérsico/epidemiologia , Causalidade , Humanos , Militares , Síndrome do Golfo Pérsico/etiologia , Síndrome do Golfo Pérsico/psicologia , Ciência , Estados Unidos/epidemiologia , Veteranos
18.
Bull Acad Natl Med ; 185(2): 373-84; discussion 384-5, 2001.
Artigo em Francês | MEDLINE | ID: mdl-11474591

RESUMO

This is the perfect example of the problems which are the consequences of the actual medicine. We carried out an ovocyte donation study at the Tenon Hospital, in Paris, between 1994 and 1999 involving 177 cryopreserved thawed embryo transfers among 300 recipients. This study enables us to stress the ethical difficulties posed by the so called bioethical laws of 1994. Simultaneously two consequences became clearly evident: a paucity of donors, and the necessity to only transfer frozen embryos due to decree of 1996 upon sanitary security that imposes the quarantine of embryos for six months. On the other hand, the use of this method has yielded important new information regarding embryo implantation and the importance of ovocyte quality that is closely correlated to donor age.


Assuntos
Bioética , Oócitos , Doadores de Tecidos/legislação & jurisprudência , França , Humanos
19.
Hum Reprod ; 15(10): 2241-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11006207

RESUMO

Education has always been a priority for the European Society of Human Reproduction and Embryology (ESHRE). Many efforts have been dedicated to promoting knowledge of techniques, procedures and strategies in order to ensure use of the highest quality practices in reproductive medicine. The need to develop a set of guidelines was a logical consequence that found its first expression in 1990, when Focus on Reproduction (vol. 1, pp. 10-38) published the first guidelines which were distributed among the membership. Five years later a new, more complete edition with several novel techniques and developments appeared in Human Reproduction (vol. 10, pp. 1246-1271). Both have proved to be invaluable references. Five more years have now passed. The necessity to produce current guidelines for good IVF laboratory practice has provided the strongest motivation. This originated from the increasing awareness that embryologists have a duty to prevent unintentional incidents that might result from poor practice in the laboratory. Therefore, the Embryology Special Interest Group (SIG) undertook to draw up guidelines aimed at giving support and guidance to the laboratory staff. All the aspects required to provide a safe working system were taken into consideration by members of the SIG and their effort produced this document. We hope that it will assist staff in achieving the best clinical outcome for their patients.


Assuntos
Fertilização in vitro , Laboratórios Hospitalares/normas , Criopreservação , Embrião de Mamíferos , Feminino , Humanos , Masculino , Oócitos , Gravidez , Diagnóstico Pré-Implantação , Controle de Qualidade , Espermatozoides
20.
Gynecol Obstet Fertil ; 28(3): 205-10, 2000 Mar.
Artigo em Francês | MEDLINE | ID: mdl-10786401

RESUMO

Many reports suggested that the high rate of miscarriage in women with polycystic ovaries may be due to increased urine and/or plasma LH concentration. In fact, with the exception of pulsatile GnRH, any treatment likely to increase the plasma LH level results in unchanged or rather low miscarriage rates. Conversely, a reduction in this rate by GnRH agonists is not conclusive. Excess weight may also increase the risk of miscarriage. In women with incipient ovarian failure, the miscarriage rate is mainly linked to age. No stimulation has been found to be effective in these patients. There is a need for more extensive evaluation in GnRH analog microdoses, recombinant FSH and GnRH antagonists. Oocyte donations from younger women are difficult to obtain because of the lack of donors in France.


Assuntos
Aborto Espontâneo/etiologia , Doenças Ovarianas/terapia , Peso Corporal , Feminino , Hormônio Foliculoestimulante/uso terapêutico , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/uso terapêutico , Humanos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Doenças Ovarianas/complicações , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/terapia , Gravidez
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