I-17: Failed Fertilization: from Molecular,Diagnostic and Clinical Perspectives

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 activating factors (SAOAFs). SOAFs are believed to be present in the perinuclear theca of sperm where it fuses with oolemma and upon its entrance into the oocyte. It activates phospholipase C zeta (PLCζ) which converts phosphatidyIinositol-4, 5- biphosphate (PIP2) to Inositol1,4,5-triphosphate (IP3) and Diacylglycerols (DAG). IP3 elicits calcium release from endoplasmic stores leading to calcium oscillations which finally leads to oocyte activation. Although PLCζ is recognized as a prominent factor involved in oocyte activation, another potential candidate is PAWP. To overcome the social and economic consequences of low and/or total failed fertilization in infertile couples undergoing ICSI, assessment of fertilization potential of a semen sample may have an empirical value in assisted reproductive techniques. We showed that quantitative assessment of these two candidates at protein and RNA levels can to certain extent predicted the fertilization potential of a semen sample. Upon such a diagnosis, the couples become nominee for artificial oocyte activation following ICSI. Artificial oocyte activation (AOA) can be achieved by mechanical, electrical or chemical means which leads to calcium raise. The latter is considered as the most common approach to induce AOA and overcome low and/or total failed fertilization. Several chemicals have been used to induce AOA including Ionophore and Ionomycin. In a series of study we showed that Ionomycin can be used as a suitable agent for AOA and in pilot study, assessing children health following AOA, we observed no adverse effect for this compound.