Inconclusive results in preimplantation genetic testing: go for a second biopsy?

Abstract

The transition in biopsy timing from blastomere to trophectoderm biopsy has led to a remarkable decrease in the percentage of undiagnosed blastocysts. However, patients with few or no euploid blastocysts can be affected by this residual percentage of diagnosis failure. The aim of this study is to assess whether blastocyst rebiopsy and revitrification is an efficient and safe procedure to be applied in cases of no results after analysis. Fifty-three patients agreed to the warming of 61 blastocysts to perform a second biopsy and PGT-A by aCGH. Only 75.4% of the blastocysts survived, reexpanded, and could be rebiopsied. After the second biopsy and analysis, 95.6% of the blastocysts were successfully diagnosed with an euploidy rate of 65.9%. Eighteen euploid blastocysts were warmed and transferred to 18 patients with a 100% survival and reexpansion rate. Seven clinical pregnancies have been achieved with 4 live births, 1 ongoing pregnancy, and 2 miscarriages. Thus, although few transfers of rebiopsied and revitrified blastocysts have been performed till date, our preliminary results show that this approach is efficient and safe to be applied for undiagnosed blastocysts, as it ultimately allows the transfer of euploid blastocysts and good clinical outcomes.

摘要

活检时间从卵裂球向滋养外胚层活检的转变显著降低了未诊断囊胚的百分比。然而, 仍有多倍体或非整倍体囊胚的患者会漏诊。本研究的目的是：假如分析后无法得出结论时, 囊胚再次活检和玻璃化冻存是否是安全有效的可行手段。纳入53名患者的61个囊胚, 复苏进行二次活检并用aCGH检测PGT-A。只有75.4% 的囊胚存活, 再扩张, 能被再活检。在二次活检和分析之后, 95.6% 的囊胚可以成功得出结果, 整倍体率是65.9%。18个整倍体囊胚复苏后移植入18个患者体内, 成活率和再扩张率都是100%。7例临床妊娠获得了4例活产, 1例继续妊娠, 2例流产。因此, 虽然进行囊胚再活检和再玻璃化冻存的病例有限, 但是研究初步的结果显示本方法是安全有效可行的, 它可以使移植的整倍体囊胚获得好的临床结局。

Keywords:

• PGT-A
• blastocyst
• biopsy
• trophectoderm
• vitrification

Disclosure statement

No potential conflict of interest was reported by the authors.