The Effect Of Different Denuding Time On Embryonic Abnormal Fertilization And Development

Objective:It is one of the common problems that fertilization failure or low fertility rate (<30%) in In Vitro Fertilization-embryo transfer cases. At present, our country medical environment is that the infertility patients have to spend their own money at the whole treatment process. If the problem was solved, it will greatly decrease patients’ economic and psychological burden. It was concerned by medical workers, that how to prevent fertilization failure or low fertility rate with reproductive medicine development. The existing of short coincubation brings premise condition for embryologists, who can observe whether oocyte activation and remedy at once. But it is not clear whether the mechanical desorption granular cells can affect normal fertilization or embryonic development potential. So the purpose of this study is to investigate whether it will affect normal fertilization, the embryo development and pregnancy by mechanical desorption granular cells.Methods:Collecting165cases of patients to accept conventional In Vitro Fertilization-embryo transfer upon5oocytes, at the age of22-38old in January2010to February2013in the reproductive center of Yancheng Maternal and Child Health-care Hospital, oocytes and sperms of each patient are incubated for4hours before eggs, then divided into two groups (A group and B group). One group, we gently remove granular cell of the number of1/3-1/2eggs after short time fertilization4hours, until it can be clearly observed oocytes’polar body. If PB2>50%, it maybe IVF fertilization success; If2PB<50%, then go on observe2hours, it is remedied to only a very body oocyte when2PB<50%after fertilization6hours. B group is the rest of the eggs, it was not demolition granular cell after short time fertilization4hours to directly transfer to fresh culture to observe pronucleus after16hours. Contrast between the two groups in total fertility rate,2PN fertilization rate, polyspermy rate,1PN fertilization rate, OPN fertilization rate, abnormal (PB) fertilization rate, total cleavage rate, I stage embryo, II stage embryo, III stage embryo, IV stage embryo and available embryonic rate and the high quality rate of embryos, clinical pregnancy, embryo transfer rate, single birth rate, the rate of twins, ectopic pregnancy, abortion number and stop number.Results:1) There were no significant differences in total fertility rate,2PN fertilization rate, polyspermy rate,1PN fertilization rate, OPN fertilization rate, abnormal (PB) fertilization rate between A group and B group (P>0.05).2) There were no significant differences in total cleavage rate, I stage embryo, II stage embryo, III stage embryo, IV stage embryo and useful embryonic rate and the high quality rate of embryos between A group and B group (P>0.05).3) The surplus embryos of A group and B group after transplantation and vitrification freezing embryos in the third day is transfered to blastocyst medium to continue to develop the blastocyst, observed blastocyst formation rate and high blastocyst formation rate, judged its development potential, The surplus embryos of blastocyst formation rate and high blastocyst formation rate of A group was significant higher than B group(P<0.05).4) The embryonic of group A and group B in the third day separately transplanted, there were no significant differences in patients age and endometrium, observe the two groups of clinical pregnancy, embryo transfer rate, single birth rate, the rate of twins, ectopic pregnancy, abortion number and stop number. There were no significant differences between group A and group B (P>0.05).Conclusion:1) There were no effect on the total fertility rate, polyspermy rate, normal fertilization rate, abnormal fertilization rate, total cleavage rate, available embryonic rate and the high quality rate of embryos by gently remove peripheral granulosa cells of oocytes after short time fertilization4hours. But it was significant effect on the blastocyst formation rate and high blastocyst formation rate with immediately demolition of granulosa cells by mechanical operation after short-term fertilization4hours.2) This way of demolition of granulosa cells after short-term fertilization4hours does not affect the overall abnormal fertilized embryos, also it won’t affect the overall embryos development potential, and it has foreseen to the remaining embryos fertilization by observing2polar body of oocytes phenomenon. At the same time, it avoides the obstacle or low fertilization happen, and improve utilization rate of embryos in infertility patients.