Department of Obstetrics and Gynecology, Faculty of Medicine, University of Montreal, Montreal, QC, Canada.
OVO Fertility Center, 8000 Decarie Blvd, Montreal, QC, H4P 2S4, Canada.
J Assist Reprod Genet. 2021 Nov;38(11):2849-2860. doi: 10.1007/s10815-021-02279-x. Epub 2021 Sep 2.
The purpose of this review and meta-analysis is to standardize the practice of mosaic embryo transfer, based on the current available evidence.
This is a systematic review and meta-analysis. Relevant studies published were comprehensively selected using PubMed, Medline, Embase, and CENTRAL until 5 March 2021. Prospective and retrospective studies reporting the genetic analysis and clinical outcomes of mosaic embryo transfer were included. Risk of bias assessment was based on the Newcastle-Ottawa scale for the non-randomized studies. The primary and secondary outcomes were combined ongoing pregnancy and live birth rate and miscarriage rate, respectively.
There were no differences between low and high mosaic embryos when a cut-off of 40% was used in terms of OP/LBR and SAB. However, low mosaics with a cut-off of 50% compared to high mosaics showed a significantly higher OP/LBR in the NGS but not in the a-CGH group, and a significantly lower risk of SAB. No differences were noted between mosaic monosomies versus trisomies and single versus double mosaics for both OP/LBR and SAB. Finally, segmental mosaics showed a higher OP/LBR and a lower SAB compared to whole chromosomes, and single and double mosaics had a higher OP/LBR compared to complex mosaics.
A cut-off of 50% in defining low versus high mosaic embryos is preferable to a threshold of 40% when using NGS platform. No priority was established for mosaic trisomies over monosomies. Single and double mosaics must be preferred over complex mosaics and segmental mosaics must be preferred over whole chromosome mosaics. These results should be interpreted in the context of specific chromosomes involved in the mosaicism.
本综述和荟萃分析旨在基于现有证据规范马赛克胚胎移植的实践。
这是一项系统综述和荟萃分析。通过使用 PubMed、Medline、Embase 和 CENTRAL 全面选择发表的相关研究，直到 2021 年 3 月 5 日。纳入报告马赛克胚胎移植的遗传分析和临床结局的前瞻性和回顾性研究。非随机研究的偏倚风险评估基于纽卡斯尔-渥太华量表。主要和次要结局分别是持续妊娠和活产率以及流产率。
当使用 40%的截止值时，低和高马赛克胚胎在 OP/LBR 和 SAB 方面没有差异。然而，与高马赛克相比，使用 50%截止值的低马赛克在 NGS 中显示出显著更高的 OP/LBR，但在 a-CGH 组中没有，并且 SAB 的风险显著降低。在 OP/LBR 和 SAB 方面，马赛克单体与三体以及单倍体与双倍体之间没有差异。最后，与整条染色体相比，节段性马赛克显示出更高的 OP/LBR 和更低的 SAB，与复杂马赛克相比，单倍体和双倍体具有更高的 OP/LBR。
当使用 NGS 平台时，定义低与高马赛克胚胎的截止值为 50%优于 40%。马赛克三体与单体之间没有优先级。单倍体和双倍体必须优先于复杂马赛克，节段性马赛克必须优先于整条染色体马赛克。这些结果应在涉及马赛克的特定染色体的背景下进行解释。
