Search results for "genetic diagnosis"
showing 10 items of 26 documents
Impact of chromosomal abnormalities on preimplantation embryo development.
2007
Objectives To evaluate the influence of numerical chromosomal abnormalities on preimplantation embryo development. Methods This study includes 6936 embryos from 1245 women undergoing preimplantation genetic diagnosis (PGD). Indications for aneuploidy screening were: recurrent miscarriages, implantation failure, severe male factor, advanced maternal age, and mixed causes. Embryo biopsy was performed on day 3, and embryos were co-cultured until day 5, when embryo transfer was performed. Results In the aneuploidy screening regimen, normal euploid embryos showed significantly higher blastocyst rates (68.2%) compared to chromosomally abnormal (42.8%, p < 0.0001) and mosaic (53.7%, p < 0.0001) em…
Vitrification of preimplantation genetically diagnosed human blastocysts and its contribution to the cumulative ongoing pregnancy rate per cycle by u…
2008
Objective To evaluate the survival rate and clinical results of our vitrification procedure on preimplantation genetic diagnosis (PGD) blastocysts and to calculate its actual contribution to the reproductive outcome per cycle. Design Retrospective clinical study. Setting University Institute IVI, Valencia, Spain. Patient(s) Patients who requested cryotransfer of surplus PGD blastocysts after failed fresh elective transfer. Intervention(s) Retrospectively collected data during 2 years of experience with blastocyst vitrification. Main Outcome Measure(s) Primary outcome measures were the following: blastocyst recovery and survival; cryotransfer cancellation; and the implantation, pregnancy (PR…
Ultrastructure of preimplantation genetic diagnosis-derived human blastocysts grown in a coculture system after vitrification
2006
Objective To evaluate ultrastructural features of preimplantation genetic diagnosis (PGD) blastocysts before and after vitrification. Design Descriptive study of both vitrified and fresh hatching blastocysts. Setting PGD program at the Instituto Universitario, Instituto Valenciano de Infertilidad. Patient(s) Patients undergoing PGD donated their abnormal embryos for research (n = 26). Intervention(s) Biopsied embryos were cultured in the presence of human endometrial cells until day 6. Sixteen blastocysts were vitrified. A total of 11 high-scored hatching blastocysts, 6 warmed and 5 fresh, were fixed for ultrastructure. Main Outcome Measure(s) The cytoskeleton structure, type of intercellul…
First trimester biochemical screening for Down's syndrome in singleton pregnancies conceived by assisted reproduction
2005
BACKGROUND: Serum biochemical markers [free betahCG (fbetahCG); pregnancy-associated plasma protein-A (PAPP-A)] used in first trimester Down's syndrome screening have not been fully investigated in pregnancies achieved by assisted reproduction techniques. We present data on pregnancies conceived by all types of assisted reproduction techniques, including pregnancies following ovum donation (OD) and a large sample by ICSI. METHODS: First trimester Down's syndrome screening was performed in 1054 normal singleton pregnancies: natural conception (n = 498), ovulation induction (OS, n = 97), IVF (n = 47), ICSI (n = 222) and OD (n = 190). RESULTS: No differences in maternal levels of fbetahCG and …
The impact of next-generation sequencing technology on preimplantation genetic diagnosis and screening.
2013
Largely because of efforts required to complete the Human Genome Project, DNA sequencing has undergone a steady transformation with still-ongoing developments of high-throughput sequencing machines for which the cost per reaction is falling drastically. Similarly, the fast-changing landscape of reproductive technologies has been improved by genetic approaches. Preimplantation genetic diagnosis and screening were established more than two decades ago for selecting genetically normal embryos to avoid inherited diseases and to give the highest potential to achieve stable pregnancies. Most recent additions to the IVF practices (blastocyst/trophectoderm biopsy, embryo vitrification) and adoption…
Secular citizens, pious MPs: why German attitudes about genetic testing are much more permissive than German laws
2020
Germany has lifted its total ban on Preimplantation Genetic Diagnosis (PGD, a form of genetic testing), but the new rules are still much stricter than those in other European countries. Results fro...
Changes in sex ratio from fertilization to birth in assisted-reproductive-treatment cycles
2014
Background: In Western gender-neutral countries, the sex ratio at birth is estimated to be approximately 1.06. This ratio is lower than the estimated sex ratio at fertilization which ranges from 1.07 to 1.70 depending on the figures of sex ratio at birth and differential embryo/fetal mortality rates taken into account to perform these estimations. Likewise, little is known about the sex ratio at implantation in natural and assisted-reproduction-treatment (ART) cycles. In this bioessay, we aim to estimate the sex ratio at fertilization and implantation using data from embryos generated by standard in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) in preimplantation gene…
Differential metabolic profiling of non-pure trisomy 21 human preimplantation embryos.
2012
Objective To investigate the metabolomic signature of trisomy 21 preimplantation human embryos by a noninvasive approach using mass spectrometry– (MS-) and nuclear magnetic resonance spectroscopy– (NMR-) based metabolic profiling platforms. Design A total of 171 spent media samples were collected from day 3 embryos and comparatively analyzed by MS analysis (chromosomally normal embryos, n=15; trisomy 21 embryos, n=15) and a matched control media group (without embryo, n=14) and by NMR spectroscopy (normal embryos, n=39; trisomy 21 embryos, n=35; monosomy 21 embryos, n=24) and a matched control media group (without embryo, n=29). Setting IVF clinic/preimplantation genetic diagnosis (PGD) uni…
Preconception genome medicine: current state and future perspectives to improve infertility diagnosis and reproductive and health outcomes based on i…
2021
Abstract BACKGROUND Our genetic code is now readable, writable and hackable. The recent escalation of genome-wide sequencing (GS) applications in population diagnostics will not only enable the assessment of risks of transmitting well-defined monogenic disorders at preconceptional stages (i.e. carrier screening), but also facilitate identification of multifactorial genetic predispositions to sub-lethal pathologies, including those affecting reproductive fitness. Through GS, the acquisition and curation of reproductive-related findings will warrant the expansion of genetic assessment to new areas of genomic prediction of reproductive phenotypes, pharmacogenomics and molecular embryology, fur…
What do French patients and geneticists think about prenatal and preimplantation diagnoses in Marfan syndrome?
2012
Objectives Marfan syndrome (MFS) is an autosomal dominant connective tissue disorder with manifestations mainly involving the skeletal, ocular, and cardiovascular systems. The phenotypic variability observed in MFS makes genetic counselling difficult. Prenatal diagnosis (PND) and preimplantation genetic diagnosis are technically feasible when a causal mutation is identified, but both raise many ethical questions in this condition. Little is known about opinions and practices in such reproductive issues in MFS. The goal of this study was to report on patients' points of view and geneticists' standard practices. Methods Two different questionnaires were produced. Results Fifty geneticists fil…