BACKGROUND This study compares the fertilization rate and embryonic development of oocytes randomly inseminated by conventional IVF or ICSI in patients with polycystic ovarian syndrome (PCOS) and normozoospermic semen during IVF cycles. METHODS Sibling oocytes were randomized to be inseminated either by ICSI or IVF. Fertilization rate (two pronuclei/COC), day 2 embryonic morphology and rate o...

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...

s:1750:"Background: We propose in this work to assess the effect of total and severe teratozoospermia on the outcome of intra cytoplasmic sperm injection( ICSI) essentially the biological side and try to highlight the factor in the success or failure of the attempt in cases of extreme or total teratozoospermia. Materials and Methods: This is a comparative retrospective study including 140 coupl...

Recent reports have suggested that when unfertilized oocytes with a spermatozoon after intracytoplasmic sperm injection (ICSI) are properly activated, the activated oocytes develop normally similar to fertilized oocytes. However, human oocytes do not easily respond to universal activators of mammalian oocytes like ethanol or calcium ionophore A23187, which induce a calcium transient in ooplasm....

A total of 740 cycles of intracytoplasmic sperm injection (ICSI) were performed: 625 cycles when < 6 x 10(5) total motile spermatozoa were harvestable from the ejaculate and 115 cycles in cases with a history of previous fertilization failure after classic in-vitro fertilization or subzonal sperm injection. An average of two pronuclei were observed in 63% of the injected oocytes, allowing 725 t...

background: conventional ivf and icsi are two common techniques to achieve fertilization. ivf has long been used for treatment of infertility, although it is not an effective treatment in severe male infertility. the use of icsi has been expanded in severe male factor and fertilization failure after ivf cycle. in spite of the widespread use of icsi in patients with non-male factor infertility, ...

Free-spawning marine invertebrates that live near shore or in estuaries may experience reduced fertilization success during low-salinity events. Although several studies have documented reproductive failure at reduced salinity in estuarine animals, few have looked at whether developmental failure is due to a failure of fertilization or to a failure of fertilized eggs to cleave. In this study, w...

A cytogenetic study was performed on uncleaved cattle oocytes after in vitro fertilization. To assess the contribution of chromosome anomalies to failure of bovine in vitro fertilization, 1044 uncleaved oocytes were investigated cytogenetically after in vitro fertilization. Uncleaved oocytes were selected after 72 h of culture post IVF and fixed for chromosomal analysis. A total of 744 oocytes ...