第二极体数目与受精结局及胚胎发育潜能的相关性

目的 探讨第二极体数目与卵母细胞受精结局和胚胎发育潜能之间的关系.方法 根据受精后5 h内卵母细胞极体数目的 不同分为1个极体组（1PB组）、2个极体组（2PB组）、3个极体组（3PB组）和4个以上极体组（≥4PB组）.分别统计各组的正常/异常受精率（2PN率,1PN和3PN率）、优质胚胎率（优胚率）、移植胚胎所占比例以及相应着床率.采用χ2检验对数据进行统计学处理.结果 ① 2PB组的2PN率显著高于其它组,而异常受精率显著低于其它组;随着第二极体数目的 增加,异常受精比例逐渐增加;② 2PB组和3PB组的胚胎着床率显著高于1PB组,以2PB组为最;③ 2PB组和3PB组用于移植的胚胎比例无显著差异.结论① 短时受精后显示有两个极体的卵母细胞其受精结局和发育潜能优于其它极体数目的 胚胎;② 随着第二极体数目的 增加,异常受精比例逐渐增加,可能与卵母细胞减数分裂或基因调控异常有关;③ 1PB组的总受精率高达48.9 %.因此,短时受精后对于仅显示一个极体的卵母细胞需要延长观察时间,谨慎确定受精与否,以防止过度早补救ICSI;④ 1PB组的着床率显著低于2PB组,也不建议首选用于移植.

Relationship between Number of Secondary Polar Body and Developing Potential of Embryos

Objective To explore the relationship between the number of secondary polar body （PB） and the developing potential of embryos. Methods According to the number of PB within oocytes after short-term fertilization, four groups were divided： 1-PB group, 2-PB group, 3-PB group and 〉 3-PB group. Several items were observed： normal/abnormal fertilization rate （2PN, 1PN and 3PN contained respectively） , top quality embryos rate, percentage of transferred embryos and implantation rate of each group. Chi-square test was used. Results ① The 2PN rate in 2-PB group was significantly higher than other groups, while the abnormal fertilization rate in 2-PB group was the lowest among the four groups. With the increase of secondary PB number, the abnormal fertilization rate was increased accordingly; ② The embryo implantation rate in 2-PB and 3-PB groups was remarkably higher than 1-PB group; ③ There was no significant difference in the transferred embryo rates between 2PB and 3PB groups. Conclusion The oocytes with 2 PB after short-term fertilization are related to the rate of total fertilization, normal fertilization, top quality embryo, erabryo utilization and implantation, inferring a high developing potential these embryos. Furthermore, along with the increase of secondary PB number （ 〉 3 PB） after short-term fertilization, the abnormal fertilization rate is increased, which may be related to the abnormal mei- osis or gene regulation. These embryos are not recommended to be transferred firstly. In addition, considering the total fertilization rate of I PB group is up to 48.9%, it is necessary to prolong the oocyte-observed time after short-term fertilization, so rescue ICSI could be avoided supplement to evaluate embryos developing potential.