Bianchi V, Coticchio G, Distratis V, Di Giusto N, Flamigni C, Borini A
Tecnobios Procreazione, Via Dante 15, 40125 Bologna, Italy.
Reprod Biomed Online. 2007 Jan;14(1):64-71. doi: 10.1016/s1472-6483(10)60765-1.
Novel protocols have increased survival and fertilization rates of cryopreserved oocytes. Nevertheless, in most cases clinical experiences have been disappointing or contradictory. Human oocytes of 141 patients were cryopreserved using a modified slow-cooling protocol involving 1.5 mol/l propane-1,2-diol (PrOH) and 0.2 mol/l sucrose during dehydration, while rehydration was conducted applying decreasing concentrations of PrOH and 0.3 mol/l sucrose. One thousand and eighty-three oocytes were frozen and 403 were thawed, with a survival rate of 75.9%. Among the 306 surviving oocytes, 252 were microinjected and 192 (76.2%) showed two pronuclei. One hundred and eighty zygotes (93.8%) cleaved. The proportion of good quality embryos (grade I and II) was 86.2%. All embryos were transferred and 17 clinical pregnancies were obtained. Pregnancy rates were 21.3% per transfer, 21.8% per patient, and 18.9% per thawing cycle. The implantation rate was 13.5% while the miscarriage rate was 11.8%. To date, four babies have been delivered, while the remaining pregnancies are ongoing. Increased oocyte survival rates can be achieved by moderately high sucrose concentrations in the freezing and thawing solutions. This also ensures elevated success rates in terms of fertilization, embryo development and clinical outcome.
新的方案提高了冷冻保存卵母细胞的存活率和受精率。然而，在大多数情况下，临床经验并不理想或相互矛盾。对141例患者的人类卵母细胞采用改良的慢速冷却方案进行冷冻保存，脱水过程中使用1.5mol/L丙二醇（PrOH）和0.2mol/L蔗糖，复水时采用浓度递减的PrOH和0.3mol/L蔗糖。共冷冻1083枚卵母细胞，解冻403枚，存活率为75.9%。在306枚存活的卵母细胞中，252枚进行了显微注射，其中192枚（76.2%）显示出两个原核。180枚受精卵（93.8%）发生分裂。优质胚胎（Ⅰ级和Ⅱ级）的比例为86.2%。所有胚胎均进行了移植，获得17例临床妊娠。移植妊娠率为21.3%，患者妊娠率为21.8%，解冻周期妊娠率为18.9%。着床率为13.5%，流产率为11.8%。迄今为止，已分娩4名婴儿，其余妊娠仍在继续。在冷冻和解冻溶液中使用适度高浓度的蔗糖可提高卵母细胞存活率。这也确保了在受精、胚胎发育和临床结局方面有更高的成功率。
