Center for Reproductive Medicine, Cleveland Clinic, Cleveland, Ohio, USA.
J Assist Reprod Genet. 2011 Sep;28(9):833-49. doi: 10.1007/s10815-011-9608-7. Epub 2011 Jul 9.
Despite an ongoing debate over its efficacy, preimplantation genetic screening (PGS) is increasingly being used to detect numerical chromosomal abnormalities in embryos to improve implantation rates after IVF. The main indications for the use of PGS in IVF treatments include advanced maternal age, repeated implantation failure, and recurrent pregnancy loss. The success of PGS is highly dependent on technical competence, embryo culture quality, and the presence of mosaicism in preimplantation embryos. Today, cleavage stage biopsy is the most commonly used method for screening preimplantation embryos for aneuploidy. However, blastocyst biopsy is rapidly becoming the more preferred method due to a decreased likelihood of mosaicism and an increase in the amount of DNA available for testing. Instead of using 9 to 12 chromosome FISH, a 24 chromosome detection by aCGH or SNP microarray will be used. Thus, it is advised that before attempting to perform PGS and expecting any benefit, extended embryo culture towards day 5/6 should be established and proven and the clinical staff should demonstrate competence with routine competency assessments. A properly designed randomized control trial is needed to test the potential benefits of these new developments.
尽管关于其疗效仍存在争议，但胚胎植入前遗传学筛查（PGS）越来越多地被用于检测胚胎中的染色体数目异常，以提高体外受精后的胚胎着床率。PGS 在体外受精治疗中的主要适应证包括高龄产妇、反复着床失败和反复妊娠丢失。PGS 的成功高度依赖于技术能力、胚胎培养质量以及胚胎植入前存在嵌合体的情况。目前，卵裂期活检是最常用于筛查胚胎非整倍体的方法。然而，由于嵌合体的可能性降低和可供检测的 DNA 量增加，囊胚活检正在迅速成为更受青睐的方法。与使用 9 到 12 个染色体 FISH 相比，将使用 aCGH 或 SNP 微阵列进行 24 个染色体检测。因此，建议在尝试进行 PGS 并期望获得任何益处之前，应建立并证明胚胎延长培养至第 5/6 天，并证明临床人员具备常规能力评估的能力。需要进行设计合理的随机对照试验来测试这些新发展的潜在益处。
