Prior to ICSI the cumulus-oophorous-complex of the oocyte is commonly remove with impure animal-derived hyaluronidase of low strength. The lower strength of the enzyme, the high concentration of impurities and the necessity of extensive time-dependent mechanical denudation damages of the oocytes, increases the risk of lysing the oocytes and the transfer of animal-derived pathogens. All this can...

BACKGROUND Normal fertilization and ongoing pregnancy can be achieved using intracytoplasmic sperm injection (ICSI), even with severely immature spermatozoa. However, the published literature documents conflicting results as to the outcome of ICSI. METHODS Surgical extraction of spermatozoa in 111 ICSI treatment cycles performed over five years at the Assisted Conception Unit (ACU), Universit...

Background: The cause of fertilization failure in IVF is most often due to the absence of sperm penetration but the reason why fertilization does not occur when intracytoplasmic sperm injection (ICSI) is applied is not clear. However some intrinsic oocyte problems may also be responsible for fertilization failure. It has been reported that 13% of unfertilized oocytes after IVF show morphologica...

An assessment of the nitrogen fertilization efficiency should not only include quantitativeand qualitative yield changes, but also an analysis of formation some indicators such as: Nharvest index (NHI), N use efficiency (NUE), N utilization efficiency (NUtE), N agronomicefficiency (NAE), N physiological efficiency (NPE) and N apparent recovery fraction (NRF).The objective of the study was the e...

Objective: To assess the influence of MII oocyte morphology on the fertilization outcome and embryo development in ART cycles. Since, age may affect the quality of oocyte, the role of women's age was also evaluated following IVF or ICSI cycles. Materials and Methods: 200 MII oocytes from 30 IVF and ICSI cycles were evaluated. The morphology of oocytes that were fertilized in IVF cycles (IVF+) w...

CAPSULE Male aging effects on aneuploidy rates in embryos. OBJECTIVE Paternal age is associated with decreasing sperm quality; however, it is unknown if it influences chromosomal abnormalities in embryos. The objective of this study is to evaluate if the aneuploidy rates in embryos are affected by advanced paternal age. METHODS A total of 286 embryos, obtained from 32 in vitro fertilization...

Asymmetric division of zygote is critical for pattern formation during early embryogenesis in plants and animals. It requires integration of the intrinsic and extrinsic cues prior to and/or after fertilization. How these cues are translated into developmental signals is poorly understood. Here through genetic screen for mutations affecting early embryogenesis, we identified an Arabidopsis mutan...