三种颗粒细胞剥除方式对卵母细胞受精率及胚胎发育的影响

Comparison of three protocols of oocyte denudation on fertilization rate and embryo quality in human IVF cycles

目的对三种颗粒细胞剥除方式在常规体外受精(IVF)中对卵母细胞受精率及胚胎发育影响进行前瞻性研究。方法2004年1～12月,因输卵管因素不育在我院生殖中心行常规体外受精-胚胎移植(IVF-ET)的患者54例,患者年龄均小于35岁。采用随机表法随机分为三组,每组18例,共818个卵母细胞。对三组卵母细胞在IVF后采取不同的颗粒细胞剥除方式:第一组在受精后4h完全剥除颗粒细胞;第二组在受精后4h部分剥除颗粒细胞,受精后16～18h再将颗粒细胞完全剥除;第三组在受精后16～18h完全剥除颗粒细胞(即传统的过夜培养方式)。对三组的受精率、优质胚胎率、囊胚形成率进行比较。结果第一组及第二组的优质胚胎率高于第三组,差异有统计学意义(P<0.05)。三组在受精率及囊胚形成率方面没有显著差别。结论第一组的颗粒细胞剥除方式最好,即缩短精-卵共培养时间可以提高胚胎质量,长时间的精-卵共培养对优质胚胎的形成有不利影响。较短时间(12～14h)的颗粒细胞与卵细胞的共培养可能对胚胎发育的质量无显著影响。

Objective： This prospective, randomized study was aimed at comparing three protocols of oocyte denudation on fertilization rate and embryo quality in human IVF cycles. Methods： From January to December in 2004, a total of 54 patients younger than 35 years old with infertility because of tube obstruction were randomly assigned into three groups, with 18 patients in each group. All the oocytes were fertilized 4hrs after oocyte retrieval. In the first group, all of the oocytes were cultured with spermatozoa for 4 h, and then denudated completely. In the second group, all of the oocytes were exposed to spermatozoa for 4 h and the granulosa cells were partially denudated, and then denudated completely 16-18 h after fertilization. While in the third group, all of the oocytes were cultured with spermatozoa for 16-18 h, then denudated completely. The fertilization rate, good quality embryo rate and blastocyst formation rate of the three groups were compared. Result ： The good embryo rate of group 1 or group 2 was significantly higher than that of group 3 （P〈 0.05）. Fertilization rate and blastocyst formation rate were not significantly different among the three groups. Conclusions： Our results demonstrated that the complete denuation of the oocytes 4 hours after fertilization has a favorable effect on embryo quality. That is to say a reduced exposure of the oocyte to spermatozoa favors embryo viability, possibly due to a decrease in potential damage from sperm metabolic waste products. Short time granulose-oocyte coculture has little effect on embryo quality.