Intracellular Ca(2+) oscillations at fertilization are responsible for triggering egg activation. The aim of this study was to examine the effect of the age of the oocyte donor and in-vitro maturation on the generation of Ca(2+) transients at fertilization. The results show that <10% of in-vivo and in-vitro matured oocytes from 19-day old mice develop to the blastocyst stage in vitro. In contra...

BACKGROUND Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder in women. The developmental competence of oocytes and embryos in PCOS patients is reduced to a certain extent (comparing to non-PCOS patients, the high quality embryo rate was decreased by 16% from the data of our centre) during the in vitro fertilization (IVF) process. Cross-talk between the oocyte and cum...

The aim of this study was to determine if a low response to gonadotrophin stimulation could be considered as an indication for intracytoplasmic sperm injection (ICSI). This prospective study included a total of 96 non-male infertile couples with six or fewer retrieved oocytes, who underwent 104 in-vitro fertilization (IVF) cycles between January 1996 and April 1997. They were randomly divided i...

Previous studies relating hormone and cytokine concentrations in follicular fluid to oocyte fertilizability were flawed by the uncertainty about the actual oocyte maturity status at the time of recovery and by the possible contribution of the male factor to failures of conventional in-vitro fertilization. This is the first study in which oocyte maturity was assessed immediately after recovery a...

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...

Background: The aim of our study was to determine the metabolic profile: glucose, triglycerides (TG), high density lipoprotein (HDL) and cholesterol (CHT) in women undergoing ART (Assisted reproductive technology) cycles and estimate its effect on In Vitro Fertilization (IVF) outcomes Materials and Methods: Forty three women undergoing IVF treatment were included in the study. Patients were all...

OBJECTIVE To investigate fertilization and embryo quality of dysmorphic mature oocytes with specific morphological abnormalities obtained from intracytoplasmic sperm injection (ICSI). METHODS The fertilization rate (FR) and embryo quality were compared among 58 dysmorphic and 42 normal form oocytes (control 1) obtained from 35 consecutive ICSI cycles, each of which yielded at least one dysmor...

Background The best time of final oocyte maturation triggering in assisted reproduction technology protocols is unknown. This time always estimated by combined follicular size and blood progesterone level. Objective The aim of this study was evaluation of the effect of delaying oocyte maturation triggering by 24 hr on the number of mature oocytes (MII) and other in vitro fertilization cycle c...

Reproductive failure in livestock can result from failure to fertilize the oocyte or embryonic loss during gestation. Although fertilization failure occurs, embryonic mortality represents a greater contribution to reproductive failure. Reproductive success varies among species and production goals but is measured as a binomial trait (i.e., pregnancy), derived by the success or failure of multip...