Taylor Tyl H, Patrick Jennifer L, Gitlin Susan A, Michael Wilson J, Crain Jack L, Griffin Darren K
Reproductive Endocrinology Associates of Charlotte, 1524 E. Morehead St., Charlotte, NC 28207, USA; University of Kent, Department of Biosciences, Canterbury CT2 7NJ, United Kingdom.
Reproductive Endocrinology Associates of Charlotte, 1524 E. Morehead St., Charlotte, NC 28207, USA.
Reprod Biomed Online. 2014 Jul;29(1):59-64. doi: 10.1016/j.rbmo.2014.03.001. Epub 2014 Mar 15.
Trophectoderm biopsy with comprehensive chromosome screening (CCS) has been shown to increase implantation and pregnancy rates. Some patients desire CCS on previously cryopreserved blastocysts, resulting in blastocysts that are thawed/warmed, biopsied, vitrified and then warmed again. The effect of two cryopreservation procedures and two thawing/warming procedures on outcomes has not been effectively studied. Cycles were divided into two groups: group 1 patients underwent a cryopreserved embryo transfer with euploid blastocysts that were vitrified and warmed once; group 2 patients had a cryopreserved embryo transfer of a euploid blastocyst that was cryopreserved, thawed/warmed, biopsied, vitrified and warmed. Groups 1 and 2 included 85 and 17 women aged 35.6 ± 3.9 and 35.3 ± 4.9 years, respectively (not significantly different). Blastocyst survival in group 1 (114/116, 98.3%) and survival of second warming in group 2 (21/24, 87.5%) was significantly different (P = 0.0354). There was no difference between biochemical (68.2% and 62.5%) and clinical (61.2% and 56.3%) pregnancy rates, implantation rate (58.4% and 52.4%) and live birth/ongoing pregnancy rate (54.0% and 47.6%) between groups 1 and 2, respectively. Although it is unconventional to thaw/warm, biopsy, revitrify and rewarm blastocysts for cryopreserved embryo transfer, the results indicate that outcomes are not compromised. Trophectoderm biopsy and screening the embryos for chromosomal abnormalities has been reported to increase implantation and pregnancy rates. There is a category of patients requesting chromosomal screening on previously cryopreserved blastocysts. This scenario requires blastocysts to be thawed/warmed, biopsied, cryopreserved, and thawed/warmed again. The effect of double cryopreservation procedures and double thawing/warming procedures on pregnancy is unknown. Patients were divided into two groups, group 1 underwent a cryopreserved embryo transfer with a chromosomally normal blastocyst that was vitrified and warmed once and group 2 included patients that had a cryopreserved embryo transfer of a chromosomally normal blastocyst that was cryopreserved, thawed/warmed, biopsied, vitrified, and rewarmed. A total of 85 and 17 women aged 35.6 ± 3.9 and 35.3 ± 4.9 years were included in groups 1 and 2, respectively. The survival rate for group 1 (114 of 116, 98.3%) compared with the second warming for group 2 (21 of 24, 87.5%) was significantly higher. There was no difference between biochemical (68.2% and 62.5%), and clinical pregnancies (61.2% and 56.3%), implantation (58.4% and 52.4%), and live birth/ongoing rates (54.0% and 47.6%) between groups 1 and 2. Although it is unconventional to twice cryopreserve and twice thaw/warm a blastocyst, our results indicate that outcomes are not compromised.
有研究表明，进行滋养外胚层活检并结合全面染色体筛查（CCS）可提高着床率和妊娠率。一些患者希望对先前冷冻保存的囊胚进行CCS，这导致囊胚需先解冻/复温、活检、玻璃化，然后再次复温。两种冷冻保存程序和两种解冻/复温程序对妊娠结局的影响尚未得到有效研究。研究将周期分为两组：第1组患者接受移植经玻璃化冷冻并仅复温一次的整倍体囊胚；第2组患者接受移植经冷冻、解冻/复温、活检、玻璃化和再次复温的整倍体囊胚。第1组和第2组分别纳入85名和17名年龄在35.6±3.9岁和35.3±4.9岁的女性（差异无统计学意义）。第1组的囊胚存活率（114/116，98.3%）与第2组再次复温后的存活率（21/24，87.5%）有显著差异（P = 0.0354）。第1组和第2组的生化妊娠率（分别为68.2%和62.5%）、临床妊娠率（分别为61.2%和56.3%）、着床率（分别为58.4%和52.4%）以及活产/持续妊娠率（分别为54.0%和47.6%）之间无差异。虽然对冷冻保存的胚胎移植而言，对囊胚进行解冻/复温、活检、再次玻璃化和再次复温的做法并不常规，但结果表明妊娠结局并未受到影响。有报道称，滋养外胚层活检及筛查胚胎染色体异常可提高着床率和妊娠率。有一类患者要求对先前冷冻保存的囊胚进行染色体筛查。这种情况需要对囊胚进行解冻/复温、活检、冷冻保存，然后再次解冻/复温。双重冷冻保存程序和双重解冻/复温程序对妊娠的影响尚不清楚。患者被分为两组，第1组接受移植经玻璃化冷冻并仅复温一次的染色体正常囊胚，第2组包括接受移植经冷冻、解冻/复温、活检、玻璃化和再次复温的染色体正常囊胚的患者。第1组和第2组分别共纳入85名和17名年龄在35.6±3.9岁和35.3±4.9岁的女性。第1组的存活率（116个中有114个，98.3%）显著高于第2组再次复温后的存活率（24个中有21个，87.5%）。第1组和第2组在生化妊娠率（分别为68.2%和62.5%）、临床妊娠率（分别为61.2%和56.3%）、着床率（分别为58.4%和52.4%）以及活产/持续妊娠率（分别为54.0%和47.6%）方面无差异。虽然对囊胚进行两次冷冻保存和两次解冻/复温并不常规，但我们的结果表明妊娠结局并未受到影响。
