Search results for "IMPLANTATION"
showing 10 items of 733 documents
Study of nucleation status in the second cell cycle of human embryo and its impact on implantation rate
2016
Objective To study nucleation status in two- and four-cell embryos and its effect on reproductive outcomes. Design Retrospective cohort study. Setting University-affiliated private center. Patient(s) A total of 1,679 embryos from 940 oocyte donation cycles from May 2012 to May 2014. Intervention(s) None. Main Outcome Measure(s) Implantation, morphokinetics, and nucleation status restoration. Result(s) Multinucleation was present in 42.53% of embryos with known implantation data at the two-cell stage; it was present in approximately 14% of them at the four-cell stage. In all, 73.4% of the embryos were multinucleated at two cells and restored their nucleation status when they cleaved into fou…
Transcriptome of early embryonic invasion at implantation sites in a murine model
2015
Successful implantation relies on the interaction between a competent embryo and a receptive endometrium. The aim of the present study was to investigate genes differentially expressed in early invasive embryonic tissue versus decidual tissue in mice. Samples were obtained from the ectoplacental cone, the immediately surrounding deciduas and from deciduas from interimplantation sites. Microarray analysis showed that 817 genes were differentially expressed between extra-embryonic tissue and the surrounding decidua and that 360 genes were differentially expressed between the different deciduas, with a high representation of developmental processes. Genes differentially expressed in the matern…
Influence of supracrestal tissue attachment thickness on radiographic bone level around dental implants: A systematic review and meta-analysis.
2019
The present systematic review and meta-analysis was carried out to determine the extent to which supracrestal tissue attachment (STA) thickness affects marginal bone loss (MBL) around dental implants. An electronic search was conducted in PubMed (MEDLINE), EMBASE, and complementary sources covering the period up to June 2018. The studies were meta-analyzed based on implant position with respect to the alveolar bone crest (crestal/supracrestal). The MBL values were categorized according to STA width (thick/thin). Of the 1062 eligible titles, nine articles were included in the review. The implants were positioned crestal or supracrestal with respect to the alveolar ridge. The difference betwe…
Heterogeneous nuclear ribonucleoprotein C1 may control miR-30d levels in endometrial exosomes affecting early embryo implantation.
2018
Study question Is there a specific mechanism to load the microRNA (miRNA), hsa-miR-30d, into exosomes to facilitate maternal communication with preimplantation embryos? Summary answer The heterogeneous nuclear ribonucleoprotein C1 (hnRNPC1) is involved in the internalization of endometrial miR-30d into exosomes to prepare for its subsequent incorporation into trophectoderm cells. What is known already Our group previously described a novel cell-to-cell communication mechanism involving the delivery of endometrial miRNAs from the maternal endometrium to the trophectoderm cells of preimplantation embryos. Specifically, human endometrial miR-30d is taken up by murine blastocysts causing the ov…
The why, the how and the when of PGS 2.0
2016
STUDY QUESTION: We wanted to probe the opinions and current practices on preimplantation genetic screening (PGS), and more specifically on PGS in its newest form: PGS 2.0? STUDY FINDING: Consensus is lacking on which patient groups, if any at all, can benefit from PGS 2.0 and, a fortiori, whether all IVF patients should be offered PGS. WHAT IS KNOWN ALREADY: It is clear from all experts that PGS 2.0 can be defined as biopsy at the blastocyst stage followed by comprehensive chromosome screening and possibly combined with vitrification. Most agree that mosaicism is less of an issue at the blastocyst stage than at the cleavage stage but whether mosaicism is no issue at all at the blastocyst st…
Assessment of embryo morphology and developmental dynamics by time-lapse microscopy: is there a relation to implantation and ploidy?
2017
Time-lapse microscopy (TLM) is an exciting novel technology with great potential for enhancing embryo selection in the embryology laboratory. This non-invasive objective assessment of embryos has provided a new tool for predicting embryo development and implantation potential. TLM detects several morphological phenomena that are often missed with static observations using conventional incubators, such as irregular divisions, blastocyst collapse and re-expansion, timing of blastocoel appearance, and timing of formation and internalization of fragments. Nevertheless, it should be recognized that conventional morphological assessment has been widely accepted as the gold standard by most embryo…
Genetic Analysis of Human Preimplantation Embryos
2016
Preimplantation development comprises the initial stages of mammalian development, before the embryo implants into the mother's uterus. In normal conditions, after fertilization the embryo grows until reaching blastocyst stage. The blastocyst grows as the cells divide and the cavity expands, until it arrives at the uterus, where it "hatches" from the zona pellucida to implant into the uterine wall. Nevertheless, embryo quality and viability can be affected by chromosomal abnormalities, most of which occur during gametogenesis and early embryo development; human embryos produced in vitro are especially vulnerable. Therefore, the selection of chromosomally normal embryos for transfer in assis…
Uterine disorders affecting female fertility: what are the molecular functions altered in endometrium?
2020
[EN]: Objective:To determine the molecular functions of genes exhibiting altered expression in the endometrium of women with uterine disorders affecting fertility. Design: Retrospective analysis integrating case and control data from multiple cohorts with endometrium gene expression in women with uterine disorders. Setting: Infertility research department affiliated with a university hospital. Patient(s): Two hundred and forty women, 121 of whom were controls, 119 of whom had endometrial adenocarcinoma (ADC), recurrent implantation failure (RIF), recurrent pregnancy loss (RPL), or stage II–IV endometriosis. Intervention(s): None. Main Outcome Measure(s): Genomewide gene expression and alter…
Sperm chromosomal abnormalities and their contribution to human embryo aneuploidy.
2018
In this work we reviewed 18 years of experience using fluorescence in situ hybridization (FISH) for sperm aneuploidy testing. We evaluated parameters associated with increased numerical sperm chromosome abnormalities and determined the male contribution to embryo aneploidies in terms of reproductive outcome by increased sperm aneuploidy. This retrospective study analyzed data from 2008 sperm samples of infertile males undergoing FISH analysis because of clinical history of repetitive implantation failure, recurrent miscarriage, impaired sperm parameters, or mixed causes. Sperm concentration was the only sperm parameter associated with FISH results—we observed a gradual increase of abnormal …
Paving the way for a gold standard of care for infertility treatment: improving outcomes through standardization of laboratory procedures.
2016
Infertility affects over 70 million couples globally. Access to, and interest in, assisted reproductive technologies is growing worldwide, with more couples seeking medical intervention to conceive, in particular by IVF. Despite numerous advances in IVF techniques since its first success in 1978, almost half of the patients treated remain childless. The multifactorial nature of IVF treatment means that success is dependent on many variables. Therefore, it is important to examine how each variable can be optimized to achieve the best possible outcomes for patients. The current approach to IVF is fragmented, with various protocols in use. A systematic approach to establishing optimum best pra…