METHODS: Retrospective analysis of time-lapse images of an embryo in vitro, which resulted in a monochorionic triamniotic pregnancy following eSET on Day 5 of development.
RESULTS: A 37-year-old female patient underwent a frozen embryo transfer cycle whereby a single vitrified/warmed embryo was transferred at the hatching blastocyst stage. The subsequent pregnancy scan revealed a monochorionic triamniotic pregnancy. Because the blastocyst was cultured in an incubator incorporating TLI, retrospective scrutiny of the digital recordings demonstrated two distinct ICM structures splitting apart, which formed during the \'8-shaped hatching\'.
CONCLUSIONS: Assisted reproductive techniques and in-vitro culture have been associated with an increased frequency of embryo splitting. This has been postulated to be linked to the in-vitro hatching method observed at the blastocyst stage of development. This case report highlights the need to objectively assess any splitting of the ICM, beyond standard grading of the quality of the ICM and the trophectoderm. Such assessments of ICM splitting should be routine practice in clinical embryology when selecting embryos for transfer.
方法:对体外胚胎延时图像进行回顾性分析,在发育的第5天eSET后导致单绒毛膜羊膜妊娠。
结果:一名37岁的女性患者接受了冷冻胚胎移植周期,在孵化囊胚阶段移植了单个玻璃化/温热的胚胎。随后的妊娠扫描显示单绒毛膜羊膜妊娠。因为胚泡是在含有TLI的培养箱中培养的,对数字录音的回顾性审查表明,两个不同的ICM结构分裂开来,在'8形影线'期间形成的。
结论:辅助生殖技术和体外培养与胚胎分裂频率增加有关。据推测,这与在胚泡发育阶段观察到的体外孵化方法有关。本案例报告强调需要客观评估ICM的任何分裂,超出ICM和滋养外胚层质量的标准等级。在选择移植胚胎时,这种ICM分裂的评估应该是临床胚胎学的常规实践。