New Hope Fertility Center, 784 Park Avenue, New York City, NY 10021, USA.
Reprod Biomed Online. 2011 Mar;22(3):299-302. doi: 10.1016/j.rbmo.2010.12.004. Epub 2010 Dec 15.
A 28-year-old patient presented for preimplantation genetic screening (PGS) for family balancing utilizing previously vitrified blastocysts and day-2 embryos. To synchronize endometrial development with the embryos to be transferred, five embryos vitrified on day 2 were warmed 3 days prior to scheduled transfer. Three of them developed to 8-, 8- and 7-cell stages, respectively, and were biopsied the next day, during which three vitrified blastocysts were warmed and the two surviving blastocysts underwent trophectoderm biopsy. The five biopsied embryos were subjected to two-probe fluorescence in-situ hybridization for chromosomes X and Y. As there were still 2 days before the scheduled embryo transfer following biopsy, the two biopsied blastocysts were re-vitrified. One blastocyst and two of the embryos vitrified on day 2 were normal for sex chromosomes; of these, one of the day-2 vitrified embryos was arrested and the other did not favour the patient's wish. The re-vitrified blastocyst, which was normal for sex chromosomes, was therefore warmed and transferred, resulting in delivery of one healthy boy. As far as is known, this is the first-reported live birth developed from a re-vitrified blastocyst that had been previously vitrified, warmed and undergone trophectoderm biopsy.
一位 28 岁的患者因家族平衡利用先前冷冻的囊胚和第 2 天胚胎进行植入前遗传学筛查 (PGS) 而就诊。为了使子宫内膜发育与待转移的胚胎同步，在预定转移前 3 天将 5 个第 2 天冷冻的胚胎解冻。其中 3 个分别发育到 8-、8-和 7 细胞阶段，次日进行活检，在此期间解冻了 3 个冷冻囊胚，并对 2 个存活的囊胚进行滋养外胚层活检。对 5 个活检胚胎进行了 X 染色体和 Y 染色体的双探针荧光原位杂交。由于活检后还有 2 天才能进行胚胎移植，因此将 2 个活检囊胚重新冷冻。一个囊胚和两个第 2 天冷冻的胚胎的性染色体正常；其中一个第 2 天冷冻的胚胎停滞不前，另一个不符合患者的愿望。因此，解冻并移植了性染色体正常的重新冷冻的囊胚，最终成功分娩了一名健康男孩。据所知，这是首例从先前冷冻、解冻和进行滋养外胚层活检的冷冻囊胚中诞生的活产婴儿。
