Kaye Leah, Will Erica Anspach, Bartolucci Alison, Nulsen John, Benadiva Claudio, Engmann Lawrence
Center for Advanced Reproductive Services, Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Connecticut Health Center, 2 Batterson Park Road, Farmington, CT, 06032-6224, USA.
J Assist Reprod Genet. 2017 Jul;34(7):913-919. doi: 10.1007/s10815-017-0940-4. Epub 2017 May 12.
The purpose of this study was to compare clinical and ongoing pregnancy rates in cycles with single embryo transfer (SET) of blastocysts cryopreserved on day 5 or day 6. Our aim was to determine whether day 6 blastocysts perform adequately to recommend SET.
Retrospective cohort study including 468 transfer cycles for 392 women younger than age 38 undergoing SET at a university-affiliated IVF clinic in the USA. A total of 261 day 5 blastocysts and 207 day 6 blastocysts for frozen-thawed SET between 2010 and 2016 were analyzed. Data included cryopreservation by both a slow freeze method and vitrification.
In total, 59.0% of day 5 SET cycles resulted in a clinical pregnancy compared to 54.1% of day 6 blastocysts (p = 0.54). Ongoing pregnancy rates from day 5 frozen-thawed blastocysts (51.7%) were comparable to day 6 (44.9%, p = 0.14). When looking at vitrified blastocysts only, there were no significant differences between day 5 and day 6 blastocysts, with a clinical pregnancy rate of 69.2% for day 5 and 72.5% for day 6 (p = 0.68).
SETs of day 6 cryopreserved blastocysts resulted in similar clinical and ongoing pregnancy rates compared to day 5, particularly after vitrification.
本研究旨在比较第5天或第6天冷冻保存的囊胚单胚胎移植（SET）周期中的临床妊娠率和持续妊娠率。我们的目的是确定第6天的囊胚是否表现良好，足以推荐进行单胚胎移植。
回顾性队列研究，纳入了美国一家大学附属体外受精诊所中392名年龄小于38岁接受单胚胎移植的女性的468个移植周期。分析了2010年至2016年间用于冻融单胚胎移植的总共261个第5天囊胚和207个第6天囊胚。数据包括慢速冷冻法和玻璃化冷冻保存。
总体而言，第5天单胚胎移植周期的临床妊娠率为59.0%，而第6天囊胚的临床妊娠率为54.1%（p = 0.54）。第5天冻融囊胚的持续妊娠率（51.7%）与第6天（44.9%，p = 0.14）相当。仅观察玻璃化囊胚时，第5天和第6天囊胚之间没有显著差异，第5天的临床妊娠率为69.2%，第6天为72.5%（p = 0.68）。
与第5天相比，第6天冷冻保存囊胚的单胚胎移植导致的临床妊娠率和持续妊娠率相似，尤其是在玻璃化冷冻后。
