Screening High Quality Embryos By Using Time-lapse Technology

Objective:In present assisted reproductive technology area, the quality of human embryos cultrued in vitro are always evaluated by static morphology evaluation. The newly developed time-lapse technology is available to monitor the whole embryo development process so as to more precisely evaluate the embryo develop potential. In this paper, we are aiming at finding out some behavior characteristics to screen high quality embryos for clinical transfer by using time-lapse technology on mono-pronuclear and nomal fertilized bi-pronuclear embryos.Materials and Methods:The mono-pronuclear embryos are clinical discarded IVF or ICSI ones. The bi-pronuclear embryos are retrieved M2oocytes which followed ICSI. All the selected embryos are cultrued in WOW (well-of-well) dish and monitored by time-lapse camera from day1morning until day5or day7when blastocysts form (Primo Vision System,5min per capture,70ms per light exposure) Laser method biopsed about10trophoderm cells for whole genome amplification and sequencing. Analysis the effects of abnormal phenomena on cleavage time, blastocyst and chromosome.Results:1. There are some abnormal phenomena during the process of early embryo development, that is abnormal cleavage, spinning, plasma contraction without cleavage, blastomere reabsorption, uneven size, wrong cleavage order, nuclear reappear or multi-nuclear.2. Among all the abnormal phenomena, spinning is the most frequently occurred one followed by abnormal cleavage, others occurred occasionally. 3. Abnormal phenomena occurr throughout the cleavages, most appear during the fist two cleavages, complex abnormal phenomena which go through several cleavages are also seen.4. Abnormal phenomena decline the embryo potential to form a blastocyst, but some can still develop to high quality blastocysts.5. None of the abnormal phenomena affect the embryo cleavage time.6. Embryos with abnormal phenomena are more prone to chromosome abnormality, however, some can spontaneously remove the abnomal blastomeres and form a nomal blastocyst.Conclusion:By using time-lapse technology to monitor the whole development of embryos in vitro, we can give a preliminary evaluation to the blastocyst potential and chromosome outline according to the abnormal phenomena such as abnormal cleavage, spinning, plasma contraction without cleavage, blastomere reabsorption, uneven size, wrong cleavage order and nuclear reappear or multi-nuclear. To further dig up kinetic indicators and determine their validity, there still the need of large scale research, especially clinical perspective study.