Saito H, Ishida G M, Kaneko T, Kawachiya S, Ohta N, Takahashi T, Saito T, Hiroi M
Department of Obstetrics and Gynecology, Yamagata University School of Medicine, Yamagata, Japan.
Gynecol Obstet Invest. 2000;49(3):145-9. doi: 10.1159/000010236.
To solve the problem of multiple pregnancies during the in vitro fertilization (IVF) and embryo transfer procedure, excess embryos must be cryopreserved for embryo transfer in future. We applied the vitrification method to cryopreservation of human embryos. A total of 31 frozen-thawed embryo transfer cycles were analyzed at the Yamagata University Hospital, Yamagata, Japan. The patients were introduced to IVF treatment and had an excess of valuable embryos to be frozen after the transfer of three fresh embryos that did not result in establishing a pregnancy. Excess human 8- to 16-cell stage embryos were exposed to vitrification solution and then frozen in liquid nitrogen. The cryoprotectant was removed by washing the embryos in media containing different concentrations of cryoprotectant. Three days after LH surge and/or 2 days after ultrasonographic ovulation the embryos were transferred. The rate of poor quality embryos significantly increased and the rate of good quality embryos decreased after thawing the embryos frozen by the vitrification method. In menstrual cycles with good quality embryo transfer, a higher rate of pregnancies was established than in the cycles in which fair or poor quality embryos were the highest grade of embryos transferred into the uterus. In total, 5 pregnancies were established from 31 embryo tansfers; 4 pregnancies were in cycles associated with the transfer of good quality embryos, and 1 pregnancy was in a cycle in which the highest grade of embryo was fair. When compared with slow embryo freezing methods, vitrification has marked advantages for clinical application in terms of cost and time. Vitrification will be an alternative method for embryo freezing.
为解决体外受精（IVF）和胚胎移植过程中的多胎妊娠问题，必须冷冻多余的胚胎以备将来进行胚胎移植。我们将玻璃化方法应用于人类胚胎冷冻保存。日本山形大学医院对总共31个冻融胚胎移植周期进行了分析。这些患者接受了体外受精治疗，在移植3个新鲜胚胎但未成功妊娠后，有多余的珍贵胚胎需要冷冻。将多余的8至16细胞期人类胚胎暴露于玻璃化溶液中，然后在液氮中冷冻。通过在含有不同浓度冷冻保护剂的培养基中洗涤胚胎来去除冷冻保护剂。在促黄体生成素激增后3天和/或超声检查排卵后2天进行胚胎移植。采用玻璃化方法冷冻的胚胎解冻后，质量差的胚胎比例显著增加，质量好的胚胎比例下降。在移植优质胚胎的月经周期中，妊娠率高于移植到子宫内的胚胎最高等级为中等或差的周期。在31次胚胎移植中总共成功妊娠5例；4例妊娠发生在与移植优质胚胎相关的周期中，1例妊娠发生在胚胎最高等级为中等的周期中。与慢速胚胎冷冻方法相比，玻璃化在成本和时间方面具有明显的临床应用优势。玻璃化将成为胚胎冷冻的一种替代方法。
