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...

oocyte activation (aoa), results in high fertilization rates. objective: this prospective, randomized, unblinded clinical study aimed to evaluate the efficiency of calcium ionophore on fertilization and pregnancy rate after intracytoplasmic sperm injection (icsi) in infertile men suffer from teratoospermia. materials and methods: thirty eight women with teratoospermic partner underwent icsi wit...

background: artificial stimulation of mouse oocyte, in the absence of sperm contribution, can induce its parthenogenic activation of oocyte. ultrasound is one of the newest methods for artificial activation of mammal oocytes, and its successful utilization in pig oocyte activation has been recently reported. our objective was to assess the effect of ultrasound on mouse oocyte activation. materi...

Objective(s): Failed fertilization after intra-cytoplasmic sperm injection (ICSI) is mainly attributed to failed oocyte activation and can be overcome by artificial oocyte activation (AOA). The present study aims to compare in vitro outcomes of ICSI following two different assisted oocyte activation chemical procedures (SrCl2 and Ionomycin) in sibling oocytes of ICSI candidates.Materials and Me...

Low and/or total failed fertilization following ICSI is a disappointing effect that some couples may face during their treatment which may have severe social and economic consequences for these infertile couples. This phenomenon has been mainly attributed to failed oocyte activation post ICSI. Researchers have regarded this failure due to the absence or deficiency of sperm associated to oocyte ...

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...

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,...

Fertilization in vivo is a complex process consisting of six steps, namely, penetration of the cumulus complex, binding of the sperm to the zona pellucida, fusion of oocyte and sperm, oocyte activation, sperm remodelling, and formation of the pronuclei. Since ICSI bypasses the first three steps any problem related to fertilization failure after ICSI arises from oocyte activation onwards. Accord...

BACKGROUND Failed fertilization occurs in 2-3% of ICSI cycles and is mainly due to lack of oocyte activation. Heterologous ICSI of patient's sperm in mouse oocytes allows discrimination between sperm- and oocyte-related aetiologies of activation failure. Assisted oocyte activation (AOA) by Ca-ionophore treatment can initiate fertilization in subsequent therapeutic ICSI. We report on diagnosis a...