Time lapse(胚胎即時監測)常用指標
5 cell 時間----time to division to 5 cells (t5),
第3次分裂時間----time period of the third cell cycle (CC3),
2 cell 到 5 cell 時間----time from 2 cell division to 5 cell division (t5-t2)
Time lapse(胚胎即時監測)仍具相當多盲點,無法取代PGD(胚胎基因染色體診斷)
65%正常染色體胚胎會形成囊胚
60%異常染色體胚胎會形成囊胚
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4915281/
Morphokinetic behavior of euploid and aneuploid embryos analyzed by time-lapse in embryoscope.
Abstract
BACKGROUND:
Embryonic aneuploidy may result in miscarriage, implantation failure, or birth defects. Thus, it is clinically necessary to avoid the selection of aneuploid embryos during in vitro fertilization treatment.
AIM:
The aim of this study was to identify the morphokinetic differences by analyzing the development of euploid and aneuploid embryos using a time-lapse technology. We also checked the accuracy of a previously described model for selection of euploid embryos based on morphokinetics in our study population.
MATERIALS AND METHODS:
It is a retrospective study of 29 cycles undergoing preimplantation genetic screening from October 2013 to April 2015 at our center. Of 253 embryos, 167 suitable for biopsy embryos were analyzed for their chromosomal status using array-comparative genome hybridization (CGH). The morphokinetic behavior of these embryos was further analyzed in embryoscope using time-lapse technology.
RESULTS:
Among the analyzed embryos, 41 had normal and 126 had abnormal chromosome content. No significant difference in morphokinetics was found between euploid and aneuploid embryos. The percentage of embryos with blastulation was similar in the euploid (65.85%, 27/41) and aneuploid (60.31%, 76/126) embryos (P = 0.76). Although hard to define, majority of the chromosomal defects might be due to meiotic errors. On applying embryo selection model from Basile et al., embryos falling within optimal ranges for time to division to 5 cells (t5), time period of the third cell cycle (CC3), and time from 2 cell division to 5 cell division (t5-t2) exhibited greater proportion of normal embryos than those falling outside the optimal ranges (28.6%, 25.9%, and 26.7% vs. 17.5%, 20.8%, and 14.3%).
CONCLUSION:
Keeping a track of time interval between two stages can help us recognize aneuploid embryos at an earlier stage and prevent their selection of transfer. However, it cannot be used as a substitute for array CGH to select euploid embryos for transfer.
沒有留言:
張貼留言