A review of 392 cycles of in-vitro fertilization (IVF) was carried out in order to identify whether any factors such as sperm concentration at insemination, sperm motility or morphology, oocyte grading, number of oocytes retrieved, patient age, follicular stimulation protocols or duration of follicular growth, could be associated with the incidence of polyploidy or completely failed fertilizati...

The oocyte is the largest cell found in multicellular organisms. Mitochondria, as the energy factories for cells, are found in high numbers in oocytes, as they provide the energy for oocyte maturation, fertilization, and embryo formation via oxidative phosphorylation. Failure of assisted reproduction is mainly attributed to oocyte aging and increased aneuploidy. As the most numerous organelle i...

Background Although ovarian tissue cryopreservation and transplantation is used for fertility preservation in patient undergoing cytotoxic treatments but obtaining good quality oocyte is still a debate. Xenotransplantation has been introduced as a reliable technique for better understanding of the transplantation conditions, but to achieve healthy embryos, the quality of obtained oocytes need t...

fertilization is triggered by changes in intracellular calcium concentration. in mammals, these transients in ooplasmic calcium concentration take the form of repetitive spikes, so called calcium oscillations (ca2+-oscillations). these oscillations are important for relieve of meiotic arrest and to induce all the other events of oocyte activation. although a surface mediated way of oocyte activ...

background: determination of oocyte fertilization and embryo quality are one of the most important purposes in art cycles. follicular fluid provides an important microenvironment for development of oocytes and some biochemical characteristics of the follicular fluid, such as pregnancy-associated plasma protein-a (papp-a), may play an important role in prediction of success rate of art. objectiv...

sperm dna is known to contribute one half of the genomic material to the offspring. the integrity of sperm dna is important in fertilization, embryonic and fetal development, and postnatal child well being. the nature has created multiple barriers that allow only the fittest sperm to reach and fertilize an oocyte. however, assisted reproductive techniques (art), like ivf and icsi, may allow spe...

Nitric oxide (NO) is a molecule involved in many reproductive processes. Its importance during oocyte in vitro maturation (IVM) has been demonstrated in various species although sometimes with contradictory results. The objective of this study was to determine the effect of NO during IVM of cumulus oocyte complexes and its subsequent impact on gamete interaction in porcine species. For this pur...

A transient increase in intracellular Ca(2+) is the universal signal for egg activation at fertilization. Eggs acquire the ability to mount the specialized fertilization-specific Ca(2+) signal during oocyte maturation. The first Ca(2+) transient following sperm entry in vertebrate eggs has a slow rising phase followed by a sustained plateau. The molecular determinants of the sustained plateau a...

We studied the effect of different storage conditions of porcine ovaries (time, temperature) on the characteristics of the follicular fluid, immature oocyte quality, meiotic competence and in vitro fertilization of oocytes. Ovaries were stored for 2, 4 or 6 h at 3 different temperatures (15 ̊C, 25 ̊C or 35 ̊C). As the storage time increased, pH and glucose concentration of the follicular fluid, pe...