Search results for "Preimplantation genetic diagnosis"
showing 10 items of 18 documents
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…
FISH screening of aneuploidies in preimplantation embryos to improve IVF outcome
2005
Preimplantation genetic diagnosis (PGD) has transformed the approach to the infertility patient in the IVF setting. Although the principal applications of PGD have been to prevent the transmission of sex-linked diseases, in time and with growing knowledge of the chromosomal abnormalities observed in preimplantation embryos, its applications have widened. Nowadays, apart from its implications in the prevention of transmission of chromosomal and genetic abnormalities, PGD is being used with increased frequency to improve the IVF outcome in patients with advanced maternal age (or =38 years of age), recurrent miscarriage (or =2 miscarriages), recurrent IVF failure (or =3 failed IVF attempts) an…
Successful application of preimplantation genetic diagnosis for hypokalaemic periodic paralysis.
2009
Hypokalaemic periodic paralysis is a rare dominant inherited disease where a person suffers sudden falls of circulating potassium concentrations, producing muscle weakness and sometimes severe paralysis. Attacks can occur as frequently as several times a day or once in a year. The age of onset is usually adolescence but symptoms can appear as early as 10 years of age. Muscle weakness can compromise vital functions such as breathing or swallowing and heart arrhythmias are also frequent during attacks. Preimplantation genetic diagnosis, an early form of prenatal diagnosis for couples at risk of transmitting inherited diseases, was used to prevent the transmission of this disease. Six polymorp…
New options in assisted reproduction technology: the Cryotop method of oocyte vitrification
2008
The Cryotop vitrification method has been shown to be a very useful tool for oocyte cryopreservation, giving excellent results regarding survival and clinical outcome. There are several clinical situations in which oocyte cryopreservation provides solutions that have not been available to date. This report describes three of these situations: (i) a low-responder patient who needed a single gene diagnosis due to the presence of a genetic disease; (ii) a patient undergoing endometrial bleeding on the day of oocyte retrieval who was also affected by a genetic disorder; and (iii) a patient who failed to become pregnant after the donation of vitrified oocytes and subsequently had the re-vitrifie…
Smoking habits of parents and male: female ratio in spermatozoa and preimplantation embryos
2005
BACKGROUND Previous observations have addressed a decreased male:female ratio associated with smoking. Our aim was to assess whether this effect is observed at the spermatozoa or at the early embryo development. METHODS We retrospectively assessed smoking intake habits of 56 couples included in our preimplantation genetic diagnosis (PGD) program. Three groups were established according to male or female cigarette consumption per day: non-smokers, smokers (1-19 cigarettes per day) and heavy smokers (> or =20 cigarettes per day). Fluorescence in-situ hybridization (FISH) was performed on ejaculated sperm samples to analyse chromosomes X and Y. On day 3, embryos were also analysed. Additionall…
Egg donation, surrogate mothering, and cloning: attitudes of men and women in Germany based on a representative survey
2009
Objective To determine opinions and attitudes of the German general population toward the treatment methods of reproductive medicine: egg donation, surrogate mothering, and reproductive cloning. Design Representative survey. Setting German general population: face-to-face interviews at home with 2,110 persons, aged 18–50 years. Patient(s) Patients were not included. Intervention(s) No interventions took place. Main Outcome Measure(s) Approval and disapproval of treatment methods of reproductive medicine and preimplantation genetic diagnosis were assessed by questionnaires regarding medical, age, reasons, or general. Result(s) Overall, the diverse treatment methods of reproductive medicine f…
Impact of preimplantation genetic diagnosis on IVF outcome in implantation failure patients
2003
Implantation failure (IF) is defined as three or more failed IVF attempts, and preimplantation genetic diagnosis (PGD) is being used in these patients to improve IVF outcome. PGD was performed in 49 implantation failure patients with a mean number of 4.2 +/- 1.6 previous IVF failures, and in nine fertile controls. Fluorescence in-situ hybridization (FISH) on blastomeres from biopsied day 3 embryos was performed for chromosomes 13, 16, 18, 21, 22, X and Y. There was a significantly higher rate of chromosomal abnormalities (67.4%) compared with controls (36.3%). In 57 cycles, a pregnancy rate of 34.0% and an implantation rate of 19.8% was observed in implantation failure patients compared wit…
Preimplantation genetic diagnosis by fluorescence in situ hybridization: clinical possibilities and pitfalls.
2003
Preimplantation genetic diagnosis using the fluorescence in situ hybridization technique (FISH) is being used widely to prevent the transmission of sex-linked diseases, to screen for translocations, and for aneuploidy screenng in specific invitro fertilization (IVF) patient groups, along with FISH analysis of spematozoa in intertile men. In this study, we aim to critically analyze our clinical results in patients at risk of transmitting sex-linked diseases (n = 55), in carriers of translocations (n = 43), in women who have recurent miscarriage (two or more miscarriages) (n = 128), recurrent IVF failure (three or more failed IVF attempts) (n = 47), and patients of advanced maternal age (37 y…
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…