Background: Failed fertilization post ICSI has been mainly attributed to the sperm’s inability to induce oocyte activation. Phospholipase C Zeta (PLCζ) is considered to be a primary factor for the induction of oocyte activation. The aim of this study was to quantitatively assess the expression of PLCζ in globozoospermic or individuals with previous low or failed fertilization in comparison to f...

Genital tract abnormalities and adverse pregnancy outcome are well known in women exposed in utero to diethylstilboestrol (DES). Data about adverse reproductive performance in women exposed to DES have been published, including controversial reports of menstrual dysfunction, poor responses after ovarian stimulation, oocyte maturation and fertilization abnormalities. We compared oocyte quality, ...

Objective The success rates of assisted reproduction technology (ART) could be developed with the improvement of ovarian stimulation protocols as well as the optimization of final oocyte maturation. The goal of this study was to compare oocyte maturation, fertilization and pregnancy rates among women with concomitant FSH administration at the time of hCG trigger and the hCG trigger alone. Mater...

Sexual reproduction depends upon meiosis for the generation of haploid gamete nuclei, which unite after fertilization to form the diploid zygote. The oocytes of most animal species arrest during meiotic prophase, and complete meiosis in response to intercellular signaling in a process called meiotic maturation. Oocyte meiotic maturation is defined by the transition between diakinesis and metaph...

We analyzed the expression of mRNAs for growth factor [epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I), basic fibroblast growth factor (bFGF) and platelet-derived growth factor A chain (PDGF-A)] and their receptor (R) by reverse transcription-polymerase chain reaction in bovine ova during oocyte maturation in vitro (0-21 hr) and after fertilization in vitro (6-144 hr: zygote...

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...

INTRODUCTION In vitro maturation (IVM) of oocytes and subsequent, in vitro fertilization (IVF) for the generation of embryos in the laboratory has important values. Growth factors are a component of a complex system of autocrine and paracrine factors that have a regulatory role in ovarian function and affect oocyte maturation. Therefore, the aim of this study is to evaluate the effect of IGF-I ...

Cumulus cells are a group of closely associated granulosa cells that surround and nourish oocytes. Previous studies have shown that cumulus cells contribute to oocyte maturation and fertilization through gap junction communication. However, it is not known how this gap junction signaling affects in vivo versus in vitro maturation of oocytes, and their subsequent fertilization and embryonic deve...

background: human chorionic gonadotropin (hcg) has been used as a replacement for the mid-cycle luteinizing hormone (lh) surge for several years. the recent arrival of recombinant dna technology has made recombinant hcg (rhcg) accessible. objective: to assess efficacy of rhcg compared to urinary hcg (uhcg) for triggering of ovulation and induction of final oocyte maturation in assisted reproduc...

Oocyte-specific genes play important roles in regulating ovarian development, principally through the proper and timely progression of oogenesis and folliculogenesis. Development of transgenic mouse models has been critical in revealing how oocyte-specific transcripts influence oocyte development and growth, integrity of the oocyte-granulosa cell complex, oocyte maturation, fertilization, and e...