55 research outputs found

    Impact of GnRH analogues on oocyte/embryo quality and embryo development in in vitro fertilization/intracytoplasmic sperm injection cycles: a case control study

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    <p>Abstract</p> <p>Background</p> <p>Despite the clinical outcomes of ovarian stimulation with either GnRH-agonist or GnRH-antagonist analogues for in vitro fertilization (IVF) being well analysed, the effect of analogues on oocyte/embryo quality and embryo development is still not known in detail. The aim of this case-control study was to compare the efficacy of a multiple-dose GnRH antagonist protocol with that of the GnRH agonist long protocol with a view to oocyte and embryo quality, embryo development and IVF treatment outcome.</p> <p>Methods</p> <p>Between October 2001 and December 2008, 100 patients were stimulated with human menopausal gonadotrophin (HMG) and GnRH antagonist in their first treatment cycle for IVF or intracytoplasmic sperm injection (ICSI). One hundred combined GnRH agonist + HMG (long protocol) cycles were matched to the GnRH antagonist + HMG cycles by age, BMI, baseline FSH levels and by cause of infertility. We determined the number and quality of retrieved oocytes, the rate of early-cleavage embryos, the morphology and development of embryos, as well as clinical pregnancy rates. Statistical analysis was performed using Wilcoxon's matched pairs rank sum test and McNemar's chi-square test. P < 0.05 was considered statistically significant.</p> <p>Results</p> <p>The rate of cytoplasmic abnormalities in retrieved oocytes was significantly higher with the use of GnRH antagonist than in GnRH agonist cycles (62.1% vs. 49.9%; P < 0.01). We observed lower rate of zygotes showing normal pronuclear morphology (49.3% vs. 58.0%; P < 0.01), and higher cell-number of preembryos on day 2 after fertilization (4.28 vs. 4.03; P < 0.01) with the use of GnRH antagonist analogues. The rate of mature oocytes, rate of presence of multinucleated blastomers, amount of fragmentation in embryos and rate of early-cleaved embryos was similar in the two groups. Clinical pregnancy rate per embryo transfer was lower in the antagonist group than in the agonist group (30.8% vs. 40.4%) although this difference did not reach statistical significance (P = 0.17).</p> <p>Conclusion</p> <p>Antagonist seemed to influence favourably some parameters of early embryo development dynamics, while other morphological parameters seemed not to be altered according to GnRH analogue used for ovarian stimulation in IVF cycles.</p

    Promising System for Selecting Healthy In Vitro–Fertilized Embryos in Cattle

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    Conventionally, in vitro–fertilized (IVF) bovine embryos are morphologically evaluated at the time of embryo transfer to select those that are likely to establish a pregnancy. This method is, however, subjective and results in unreliable selection. Here we describe a novel selection system for IVF bovine blastocysts for transfer that traces the development of individual embryos with time-lapse cinematography in our developed microwell culture dish and analyzes embryonic metabolism. The system can noninvasively identify prognostic factors that reflect not only blastocyst qualities detected with histological, cytogenetic, and molecular analysis but also viability after transfer. By assessing a combination of identified prognostic factors—(i) timing of the first cleavage; (ii) number of blastomeres at the end of the first cleavage; (iii) presence or absence of multiple fragments at the end of the first cleavage; (iv) number of blastomeres at the onset of lag-phase, which results in temporary developmental arrest during the fourth or fifth cell cycle; and (v) oxygen consumption at the blastocyst stage—pregnancy success could be accurately predicted (78.9%). The conventional method or individual prognostic factors could not accurately predict pregnancy. No newborn calves showed neonatal overgrowth or death. Our results demonstrate that these five predictors and our system could provide objective and reliable selection of healthy IVF bovine embryos

    In vitro fertilization does not increase the incidence of de novo copy number alterations in fetal and placental lineages

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    Although chromosomal instability (CIN) is a common phenomenon in cleavage-stage embryogenesis following in vitro fertilization (IVF)1,2,3, its rate in naturally conceived human embryos is unknown. CIN leads to mosaic embryos that contain a combination of genetically normal and abnormal cells, and is significantly higher in in vitro-produced preimplantation embryos as compared to in vivo-conceived preimplantation embryos4. Even though embryos with CIN-derived complex aneuploidies may arrest between the cleavage and blastocyst stages of embryogenesis5,6, a high number of embryos containing abnormal cells can pass this strong selection barrier7,8. However, neither the prevalence nor extent of CIN during prenatal development and at birth, following IVF treatment, is well understood. Here we profiled the genomic landscape of fetal and placental tissues postpartum from both IVF and naturally conceived children, to investigate the prevalence and persistence of large genetic aberrations that probably arose from IVF-related CIN. We demonstrate that CIN is not preserved at later stages of prenatal development, and that de novo numerical aberrations or large structural DNA imbalances occur at similar rates in IVF and naturally conceived live-born neonates. Our findings affirm that human IVF treatment has no detrimental effect on the chromosomal constitution of fetal and placental lineages

    Targeting the poorest in a performance-based financing programme in northern Cameroon

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    Performance-Based Financing (PBF) is a promising approach to improve health system performance in developing countries, but there are concerns that it may inadequately address inequalities in access to care. Incentives for reaching the poor may prove beneficial, but evidence remains limited. We evaluated a system of targeting the poorest of society (‘indigents’) in a PBF programme in Cameroon, examining (under)coverage, leakage and perceived positive and negative effects. We conducted a documentation review, 59 key informant interviews and 33 focus group discussions with community members (poor and vulnerable people—registered as indigents and those not registered as such). We found that community health workers were able to identify very poor and vulnerable people with a minimal chance of leakage to non-poor people. Nevertheless, the targeting system only reached a tiny proportion (≤1%) of the catchment population, and other poor and vulnerable people were missed. Low a priori set objectives and implementation problems—including a focus on easily identifiable groups (elderly, orphans), unclarity about pre-defined criteria, lack of transport for identification and insufficient motivation of community health workers—are likely to explain the low coverage. Registered indigents perceived improvements in access, quality and promptness of care, and improvements in economic status and less financial worries. However, lack of transport and insufficient knowledge about the targeting benefits, remained barriers for health care use. Negative effects of the system as experienced by indigents included negative reactions (e.g. jealousy) of community members. In conclusion, a system of targeting the poorest of society in PBF programmes may help reduce inequalities in health care use, but only when design and implementation problems leading to substantial under-coverage are addressed. Furthermore, remaining barriers to health care use (e.g. transport) and negative reactions of other community members towards indigents deserve attention

    Targeting the poorest in a performance-based financing programme in northern Cameroon

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    textabstractPerformance-Based Financing (PBF) is a promising approach to improve health system performance in developing countries, but there are concerns that it may inadequately address inequalities in access to care. Incentives for reaching the poor may prove beneficial, but evidence remains limited. We evaluated a system of targeting the poorest of society ('indigents') in a PBF programme in Cameroon, examining (under)coverage, leakage and perceived positive and negative effects. We conducted a documentation review, 59 key informant interviews and 33 focus group discussions with community members (poor and vulnerable people - registered as indigents and those not registered as such). We found that community health workers were able to identify very poor and vulnerable people with a minimal chance of leakage to non-poor people. Nevertheless, the targeting system only reached a tiny proportion (≤1%) of the catchment population, and other poor and vulnerable people were missed. Low a priori set objectives and implementation problems - including a focus on easily identifiable groups (elderly, orphans), unclarity about pre-defined criteria, lack of transport for identification and insufficient motivation of community health workers - are likely to explain the low coverage. Registered indigents perceived improvements in access, quality and promptness of care, and improvements in economic status and less financial worries. However, lack of transport and insufficient knowledge about the targeting benefits, remained barriers for health care use. Negative effects of the system as experienced by indigents included negative reactions (e.g. jealousy) of community members. In conclusion, a system of targeting the poorest of society in PBF programmes may help reduce inequalities in health care use, but only when design and implementation problems leading to substantial under-coverage are addressed. Furthermore, remaining barriers to health care use (e.g. transport) and negative reactions of other community members towards indigents deserve attention

    Syncytin-1 and its receptor is present in human gametes

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    MAIN PURPOSE AND RESEARCH QUESTION: To determine whether the true fusogen Syncytin-1 and its receptor (ASCT-2) is present in human gametes using qRT-PCR, immunoblotting and immunofluorescence. METHODS: Donated oocytes and spermatozoa, originating from a fertility center in tertiary referral university hospital, underwent qRT-PCR, immunoblotting and immunofluorescence analyzes. RESULTS: Quantitative RT-PCR of sperm samples from sperm donors showed that syncytin-1 is present in all samples, however, protein levels varied between donors. Syncytin-1 immunoreactivity predominates in the sperm head and around the equatorial segment. The receptor ASCT-2 is expressed in the acrosomal region and in the sperm tail. Moreover, ASCT-2, but not syncytin-1, is expressed in oocytes and the mRNA level increases with increasing maturity of the oocytes. CONCLUSIONS: Syncytin and its receptor are present in human gametes and localization and temporal appearance is consistent with a possible role in fusion between oocyte and sperm
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