STUDY QUESTION Could the mitochondrial DNA (mtDNA) content of cumulus granulosa cells (CGCs) be related to oocyte competence? SUMMARY ANSWER The quality of embryos obtained during IVF procedures appears to be linked to mtDNA copy numbers in the CGCs. WHAT IS KNOWN ALREADY Oocyte quality is linked to oocyte mtDNA content in the human and other species, and the mtDNA copy number of the oocyte...

Influence of oxidative stress on oocyte quality and protective role of melatonin as an antioxida Poor oocyte quality is an important cause of female infertility. Reactive oxygen species (ROS) are produced within ovarian follicles, especially during ovulation process, and it is thought that increased ROS activity may be a cause of impaired oocyte maturation. Pineal hormone, melatonin, is detecte...

2012 School of Biological Science 2 Acknowledgements I would like to acknowledge, with appreciation, everyone who has contributed to this research. Firstly I would like to thank my primary supervisor Professor Ken McNatty for making it possible for me to do this research and for his patience and understanding in the face of some dumb moments on my part. I couldn't have completed this without hi...

In women, oocytes arrest development during prophase of meiosis I and remain inactive for years. Over time the quality and quantity of these oocytes decreases; therefore, fertility declines as human females age. C. elegans display a similar trend showing a decrease in the quality of oocytes as they grow older. Oocyte quality is assayed in C. elegans by determining the fraction of oocytes that p...

Recent studies challenge the previous view that apoptosis within the granulosa cells of the maturing ovarian follicle is a reflection of aging and consequently a marker for poor quality of the contained oocyte. On the contrary, apoptosis within the granulosa cells is an integral part of normal development and has limited predictive capability regarding oocyte quality or the ensuing pregnancy ra...

PURPOSE To investigate the direct relationship between the follicular fluid (FF) level of soluble human leukocyte antigen G (HLA-G) and fertilizability of the corresponding oocyte as well as the morphological quality of the corresponding embryo. MATERIALS AND METHODS Sixty-three patients were stimulated with recombinant FSH combined with gonadotropin-releasing hormone (GnRH) agonist long (n=5...

BACKGROUND Abnormalities of oocyte morphology affect embryo quality and viability. Whether morphological abnormalities of the oocyte influence cryosurvival and further development of derived embryos is not known. The aim of this study was to compare cryosurvival and progression to the blastocyst stage of frozen-thawed embryos derived from normal and abnormal oocytes. METHODS A total of 5292 G...

Gametes and embryo tissues are known to represent a sensitive target to environmental toxicants exposure. Oocyte quality can impact subsequent developmental competence, pregnancy course and even adult health. The major health concern from depleted uranium (DU) is mainly centred on its chemotoxic properties as a heavy metal. Little attention was paid to the impact of uranium on female gamete qua...

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...

OBJECTIVE The present study aimed to simultaneously evaluate the association between expression of three potential factors [post-acrosomal sheath WW domain-binding protein (PAWP), phospholipase Cζ (PLCζ), and truncated form of the kit receptor (TR-KIT)] as candidates of oocyte activation with fertilization rate and early embryonic development. MATERIALS AND METHODS In this experimental study,...