GENOMA Molecular Genetics Laboratory, Rome, Italy.
Curr Opin Obstet Gynecol. 2012 Aug;24(4):203-9. doi: 10.1097/GCO.0b013e328355854d.
Embryo assessment is a crucial component to the success of IVF. A high rate of embryos produced in vitro present chromosomal abnormalities and have reduced potential for achieving a viable pregnancy. The use of preimplantation genetic diagnosis by array comparative genomic hybridization, for comprehensive aneuploidy screening of embryos, to improve IVF outcomes, is reviewed.
Data from comprehensive aneuploidy screening of embryos showed that aneuploidies may occur in any of the 24 chromosomes, indicating that aneuploidy screening of all chromosomes is necessary to determine whether an embryo is chromosomally normal. Initial studies on clinical application of this technology have documented improved pregnancy outcomes following transfer of screened embryos. The optimal stage of preimplantation development at which preimplantation genetic screening (PGS) should be performed still remains to be determined.
Although clinical results have been promising, further evidence is required to establish whether PGS results in enhanced live birth rate, and if this is the case, to identify which patients may benefit from the procedure. The results from several ongoing randomized controlled trials, performed at different cell biopsy stage and categories of patients, will provide the data needed to accept or reject the clinical efficacy of PGS.
胚胎评估是体外受精成功的关键组成部分。体外产生的胚胎中存在染色体异常的比例很高，其达到可存活妊娠的潜力降低。通过使用基于阵列比较基因组杂交的胚胎植入前遗传学诊断进行胚胎全面非整倍体筛查，以提高体外受精的结局，这一方法得到了回顾。
胚胎全面非整倍体筛查的数据表明，非整倍体可能发生在 24 条染色体中的任何一条，这表明需要对所有染色体进行非整倍体筛查，以确定胚胎是否染色体正常。该技术临床应用的初步研究记录了在移植筛查胚胎后妊娠结局的改善。但仍需确定胚胎植入前遗传学筛查（PGS）应在胚胎发育的哪个最佳阶段进行。
尽管临床结果很有前景，但仍需要更多的证据来确定 PGS 是否能提高活产率，如果是这样，还需要确定哪些患者可能从该程序中受益。目前正在进行的几项随机对照试验，在不同的细胞活检阶段和不同类别的患者中进行，将提供接受或拒绝 PGS 临床疗效所需的数据。
