Lin Pin-Yao, Lee Chun-I, Cheng En-Hui, Huang Chun-Chia, Lee Tsung-Hsien, Shih Hui-Hsin, Pai Yi-Ping, Chen Yi-Chun, Lee Maw-Sheng
Institute of Medicine, Chung Shan Medical University, No. 110, Sec. 1, Jianguo N. Rd., South District, Taichung City 40201, Taiwan.
Division of Infertility, Lee Women's Hospital, No. 30-6, Sec. 1, Changping Road, Beitun District, Taichung City 406, Taiwan.
J Clin Med. 2020 Jun 2;9(6):1695. doi: 10.3390/jcm9061695.
Recently, reports showed that embryos identified as mosaic after preimplantation genetic testing for aneuploid (PGT-A) could result in live birth with lower pregnancy and higher pregnancy loss rates compared with euploid embryos. However, the effects of mosaicism level on reproductive outcomes remain controversial. This study aimed to examine the level of mosaicism on pregnancy outcomes. Single mosaic embryo transfer was offered to 108 women who only had mosaic embryos. Mosaic embryos were labeled by utilizing next generation sequencing (NGS) based PGT-A for day 5/6 trophectoderm (TE)biopsies. TE biopsies containing < 50% abnormal cells were classified as low-level mosaicism and ≥ 50% as high-level mosaicism. To further confirm the concordance of chromosome constitution between TE and inner cell mass (ICM), 41 remaining embryos designated as mosaic blastocysts donated for research were also analyzed. Comparable live birth rate (LBR) but higher miscarriage rate (MR) was found in the high-level group. (LBR: low vs. high: 44.5% vs. 36%; = 0.45, MR: low vs. high: 5.1% vs. 30.7%; = 0.012). Analyses of TE and ICM from the remaining mosaic blastocysts show a poor concordance. This preliminary study demonstrated that high-level mosaic embryos could result in comparable LBR but higher MR.
最近，有报告显示，在胚胎植入前非整倍体基因检测（PGT-A）后被鉴定为嵌合体的胚胎，与整倍体胚胎相比，可能会导致活产，但妊娠率较低且流产率较高。然而，嵌合水平对生殖结局的影响仍存在争议。本研究旨在探讨嵌合水平对妊娠结局的影响。对108名仅有嵌合胚胎的女性进行了单嵌合胚胎移植。利用基于下一代测序（NGS）的PGT-A对第5/6天的滋养外胚层（TE）活检样本进行嵌合胚胎标记。TE活检样本中异常细胞<50%的被归类为低水平嵌合，≥50%的被归类为高水平嵌合。为了进一步确认TE和内细胞团（ICM）之间染色体构成的一致性，还对另外41个被指定为嵌合囊胚且捐赠用于研究的胚胎进行了分析。结果发现，高水平组的活产率（LBR）相当，但流产率（MR）较高。（LBR：低水平组与高水平组：44.5%对36%；P=0.45，MR：低水平组与高水平组：5.1%对30.7%；P=0.012）。对其余嵌合囊胚的TE和ICM分析显示一致性较差。这项初步研究表明，高水平嵌合胚胎可能会导致相当的LBR，但MR较高。
