introduction: the incidence of chromosomal abnormalities was investigated in untransfered embryos reuslted from in vitro fertilization (ivf) or intracytoplasmic sperm injection (icsi) procedures. materials and methods: a total of 238 embryos of varying morphology between the pronucleated stage and 8-cells were analysed. the cytogenetic method of dyban was used for chromosome preparation. embryo...

background: selecting the best embryo for transfer, with the highest chance of achieving a vital pregnancy, is a major goal in current in vitro fertilization (ivf) technology. the high rate of embryonic developmental arrest during ivf treatment is one of the limitations in achieving this goal. chromosomal abnormalities are possibly linked with chromosomal arrest and selection against abnormal f...

Morphologic abnormalities in the oocyte are relevant for determining its developmental fate and could be related to controlled ovarian stimulation protocols and ovarian response. The contributing factors of oocyte dysmorphism incidence and its effects on fertilization potential and embryo development are the object of discussion in this study.

If no fertilization occurs at an appropriate time after ovulation, oocyte quality deteriorates rapidly as a process called postovulatory aging. Because the postovulatory aging of oocytes has detrimental effects on embryo development and offspring, many efforts have been made to prevent oocyte aging. Here we showed that quercetin prevented the decline in oocyte quality during postovulatory aging...

The monoclonal antibody MH27 recognizes an adherens junction protein present around hypodermal cells in the pharynx and the intestine. By using this antibody and an antiserum against the LIN-26 protein, which is present in hypodermal and glial-like cells, I have examined the morphogenesis of the embryo in embryos homozygous for 91 chromosomal deficiencies that cover approximately 74% of the Cae...

Background: Abnormal oocyte morphology has been associated with the hormonal environment to which the gametes are exposed. In this study, we evaluated the oocytes morphology, fertilization rate, embryos quality, and implantation rate resulted of retrieved oocytes in different times after human chorionic gonadotrophin (hCG) administration. Materials and Methods: A total of 985 metaphase II were ...

Abstract For decades we have looked for marker of embryo competence. And while come a long way in terms identifying markers related to embryonic competence, lot research is still focused on finding this simple measurable indicator predicting positive outcome the individual treatment. Many potential indicators been evaluated. This includes cumulus oocyte complex, zona pellucida, perivitelline sp...

Early life-stage bioassays have been used as an alternative to short-term adult toxicity tests since they are cost-effective. A single couple can produce hundreds or thousands of embryos and hence can be used as a simple high-throughput approach in toxicity studies. In the present study, zebrafish and sea urchin embryo bioassays were used to test the toxicity of four pharmaceuticals belonging t...

The premature death (p) mutation is a recessive lethal, which, in the homozygous condition, gives rise to a complex of abnormalities. The mutant embryos develop only to stage 37, at which time disintegration of superficial tissue begins. Many of the abnormalities observed in sections of the stage-37 mutant embryo are related to its failure to establish a functioning circulatory system, or to th...

Making use of advancements in molecular biology techniques, as well as a better understanding of the human genome, researchers have identified numerous alleles (gene variants) which are associated with certain diseases. In familial cases these problematic alleles are passed on from parent to offspring. Recently, couples have elected to undergo Preimplantation Genetic Diagnosis (PGD) in order to...