Blastocysts can be rebiopsied for preimplantation genetic diagnosis and screening

Objective: To evaluate the clinical value of re-examining the test-failure blastocysts in preimplantation genetic diagnosis/screening cycles.

Design: Retrospective study.

Setting: University-affiliated center.

Patient(s): Women with test-failure blastocysts cryopreserved in preimplantation genetic diagnosis/screening cycles.

Intervention(s): Cryopreserved test-failure blastocysts were warmed and underwent a second round of biopsy, single nucleotide polymorphism microarray analysis, and vitrification, and the normal blastocysts were warmed again for ET.

Main outcome measure(s): The percentage of test-failure blastocysts for transfer, the implantation rate per transferred blastocyst, and the live birth rate.

Result(s): A total of 106 test-failure blastocysts from 77 cycles were warmed for re-examination. A total of 73 blastocysts that completely expanded were considered to have survived the warming process and were successfully rebiopsied. After single nucleotide polymorphism array analysis, 70 blastocysts yielded whole genome amplification product, and 31 had normal chromosomes (44.3%). A total of 19 normal blastocysts were warmed for ET, of which 18 survived and were transferred. The clinical pregnancy rate (implantation rate) was 50.0% in 10 single blastocyst transfer cycles, and all the implanted blastocysts resulted in healthy live births.

Conclusion(s): Test-failure blastocysts that survived from the first warming procedure can tolerate a second round of biopsy, vitrification, and warming, have a high chance of having normal chromosomes, and are worth being re-examined.