Embryology Department, The Centre For Reproductive and Genetic Health, 230-232 Great Portland St., London, W1W 5QS, UK.
Clinical Department, The Centre For Reproductive and Genetic Health, 230-232 Great Portland St., London, W1W 5QS, UK.
J Assist Reprod Genet. 2018 Aug;35(8):1509-1517. doi: 10.1007/s10815-018-1246-x. Epub 2018 Jul 6.
The aim of the study is to investigate how blastocyst contraction behaviour affects the reproductive competence in high-quality euploid embryos.
Eight hundred ninety-six high-quality blastocysts derived from 190 patients (mean age 38.05 (SD = 2.9) years) who underwent preimplantation genetic testing for aneuploidies (PGT-A) from January 2016 to October 2017 were included in this study. PGT-A results were reported as euploid or aneuploid. Aneuploid embryos were sub-classified into three categories: monosomy, trisomy and complex aneuploid. Retrospective studies of time-lapse monitoring (TLM) of those embryos were analysed and reproductive outcome of transferred embryos was collected.
A total of 234/896 were euploid (26.1%) whilst 662/896 (73.9%) blastocysts were proven to be aneuploid from which 116 (17.6%) presented monosomies, 136 (20.5%) trisomies and 410 (61.9%) were complex aneuploid. The most frequent chromosomal complements were trisomies affecting chromosome 21 and monosomies involving chromosomes 16 and 22. Data analysis showed a statistical difference in the number of contractions being reported greater in aneuploid when compared to euploid embryos (0.6 vs 1.57; p < 0.001). Analysis of the aneuploid embryos showed that monosomies present less number of contractions when compared to embryos affected with trisomies or complex aneuploidies (1.23 vs 1.53 and 1.40; p < 0.05). No difference was observed when comparing the latter two groups. Euploid embryos presenting at least one contraction resulted in lower implantation and clinical pregnancy rates when compared to blastocysts that do not display this event (47.6 vs 78.5% and 40.0 vs 59.0% respectively).
Most aneuploid blastocysts diagnosed by PGT-A have complex aneuploidies, showing that aneuploid embryos can develop after genomic activation and reaching high morphological scores. It becomes clear that embryo contraction, despite being a physiological feature during blastulation, is conditioned by the ploidy status of the embryo. Furthermore, the presence of contractions may compromise implantation rates.
本研究旨在探讨囊胚收缩行为如何影响高质量整倍体胚胎的生殖能力。
本研究纳入了 190 名患者（平均年龄 38.05（SD=2.9）岁）的 896 个高质量囊胚，这些患者于 2016 年 1 月至 2017 年 10 月接受了胚胎植入前非整倍体检测（PGT-A）。PGT-A 结果报告为整倍体或非整倍体。对这些胚胎的时间 lapse 监测（TLM）进行回顾性研究，并收集了移植胚胎的生殖结果。
234/896 个为整倍体（26.1%），而 662/896 个囊胚被证实为非整倍体，其中 116 个（17.6%）为单体，136 个（20.5%）为三体，410 个（61.9%）为复杂非整倍体。最常见的染色体倍数是影响 21 号染色体的三体和涉及 16 号和 22 号染色体的单体。数据分析显示，非整倍体胚胎的收缩次数明显少于整倍体胚胎（0.6 比 1.57；p<0.001）。对非整倍体胚胎的分析表明，单体的收缩次数明显少于三体或复杂非整倍体胚胎（1.23 比 1.53 和 1.40；p<0.05）。后两者之间没有差异。与没有发生这种情况的囊胚相比，至少有一次收缩的整倍体胚胎的着床和临床妊娠率较低（分别为 47.6%比 78.5%和 40.0%比 59.0%）。
通过 PGT-A 诊断的大多数非整倍体囊胚具有复杂的非整倍性，表明非整倍体胚胎在基因组激活后可以发育并达到高形态评分。很明显，胚胎收缩虽然是囊胚形成过程中的一种生理特征，但受到胚胎倍性状态的影响。此外，收缩的存在可能会降低着床率。
