Vitrifying oocytes is a potentially valuable means of preserving the female germ line, but significantly compromises oocyte developmental competence. This study examined the hypothesis that the cumulus complex protects the oocyte during vitrification. Vitrified-warmed immature cumulus oocyte complexes (COCs) were labelled with a plasma membrane impermeant DNA marker (ethidium homodimer-1) to ex...

BACKGROUND While a complete failure of meiotic maturation following hCG administration is rare during IVF cycles, cases arise in which patients repeatedly display a high incidence of failure to complete maturation to metaphase II (MII) in vivo. For the immature oocytes of such patients, our objectives were (i) to ask whether progression to MII could be supported in vitro, and (ii) to define the...

Assisted reproductive technologies in all mammals are critically dependent on the quality of the oocytes used to produce embryos. For reasons not fully clear, oocytes matured in vitro tend to be much less competent to become fertilized, advance to the blastocyst stage, and give rise to live young than their in vivo-produced counterparts, particularly if they are derived from immature females. H...

Background: In recent years, the widespread use of microwave producing instruments specially mobile phones; result in growing concern regarding the possible effects associated with these waves on human health. Some studies highlight the possible health hazards of electromagnetic fields (EMF), while others contest the hypothesis of biological impact of EMF. The aim of this study was to evaluate ...

background: this study was aimed to assess the effects of angiotensin ii (ang ii) supplementation to the in vitro maturation (ivm) and in vitro culture (ivc) media of vitrified-warmed ovine oocytes on their developmental competence and expression of na+/k+/atpase in resulting embryos. methods: the slaughterhouse-derived immature oocytes (n=1069) were randomly distributed into four experimental ...

In canine species, in vitro maturation (IVM) rates of oocytes collected from anoestrous ovaries are low (<20%). Several IVM media have been tested without significant improvements. A critical step in the evaluation of culture conditions is the observation of the meiotic stage reached by the oocytes. The present study was designed to investigate the chromatin patterns of in vitro matured oocytes...

A major side-effect of controlled ovarian stimulation (COS) in patients with polycystic ovarian syndrome (PCOS) is the risk of ovarian hyperstimulation syndrome (OHSS). In-vitro maturation (IVM) of immature oocytes represents a potential alternative for the fertility treatment of these patients. Two patients at high risk of OHSS were primed with 10,000 IU HCG 36 h before oocyte retrieval. After...

The slaughtered cows or heifers have a large number of immature oocytes within primordial follicles or developing follicles. Therefore, it is useful to aspirate immature oocytes, which would be wasted if left unprocessed, from ovaries; subsequently they are matured in vitro (IVM), fertilized in vitro (IVF), and cultured in vitro (IVC). Also most recently it has been shown that immature oocytes ...

Cryopreservation of embryos, oocytes, or ovarian tissues is the main option for female fertility preservation. Oocyte cryopreservation has emerged as especially important: the dramatic increase in the number of infants born from vitrified oocytes indicates that it is becoming one of the most important intervention options. However, oocyte cryopreservation with standard controlled ovarian hypers...

The aim of this study was to evaluate the effect of ethylene glycol (EG) concentration, equilibration time, and the use of two disaccharides in the vitrification solution used on immature bovine oocytes that were thawed and then matured in vitro. Factorial combinations of the following were tested: three equilibration solutions (ES), containing 3, 20 or 40% EG; three equilibration times, 0.5, 5...