The Preliminary Use Of The Observation Of Human Oocytes' Spindles In The IVF Clinic Center

OBJECTIVE: (1) To observe the accurate position of spindles in metaphase II(MII) human oocytes and provide the evidence for safety of ICSI procedure. (2) To observe the relationship between the exist of spindles in Mil oocytes and the normal fertilization rate , abnormal fertilization rate , the cleavage rate and good embryos rate in day 3. (3 ) To analysis the relationship between the early cleavage and the quality of embryos. To detect whether the exist of the Mil oocyte's spindle predicts the early cleavage of the normal fertilized oocyte. ( 4 ) To observe the effect of the environmental temperature on spindles in Mil oocytes. METHODS: (1) The position of meiotic spindles were examined in 36 patients undergoing ICSI treatment. The oocytes were divided into 4 groups according to the angle between the first polar body and spindle. These groups were 0 degree, 0-80 degree, 80-100 degree and >100 degree group. At the same time, the angles were compared between the in-vivo matured human oocytes and in vitro matured oocytes. (2) Human Mil oocytes' spindles were imaged using the Polscope in 50 patients. Mil oocytes were divided into two groups according to whether the spindle was visualized. The normal fertilization rate , abnormal fertilization rate , the cleavage rate and good embryos rate were analyzed in two groups. (3) The embryos that possessed two cells at 25-27 h post ICSI were designated as 'early cleavage'(EC) embryos and those that had not yet cleaved were classified as 'no early cleavage'(NEC) embryos. The high quality embryos rates were compared in the EC group and the NEC group. (4) The structure change of the Mil unfertilizedoocytes' spindles were examined at the room temperature in 40 patients after regular in vitro fertilization. There were three different groups according to the keeping time after disappearing of the spindles at the room temperature. The three different groups were the 0, 5, and 10 min group.RESULTS'. (1 )There were 40 oocytes in the in-vitro group and 35 oocytes in the in-vivo group. 5.9% of in vitro matured oocytes and 7.7% of in vivo matured oocytes located in the 0 degree group. 88.2% and 88.5% of Mil oocytes located in the 0-80 degree group. 5.9% and 3.8% belonged to the >100 degree group. There was no oocyte in the 80-100 degree group in spite of the matuation mode. The data were analyzed in 16 patients who have both the in vitro matured oocytes and in vivo matured oocytes. The in-vitro group showed a mean deviation of the spindle from the polar body of 25.9 degree and the in-vivo group of 44.7 degree. The difference between the angle of the two groups was statistically significant(P=0.006). (2) The difference of normal fertilization rate(P=0.018), high quality embryos rate(P=0.041) between the two groups were both statistically significant. However, the difference of cleavage rate of normal fertilized oocytes between the two groups was not significant(P>0.05). ( 3 ) The value of rs was 0.422, P=0.000. The difference of high quality embryos rate between the EC group and the NEC group was statistically significant(P=0.001). (4) The spindles of the 20 unfertilized Mil oocytes disappeared after lying them at the room temperature for 5 min. The 8 oocytes' spindles reappeared in the group 1. All of the 6 group 2 oocytes' spindles reappeared also. There are only half of the oocytes' spindles reappeared in the group 3. In the control group, spindles' images did not change in the 18 oocytes that had been kept at 37C during 30 min of examination. CONCLUSIONS'. (1) The first polar body of human oocyte doesnot predict accurately the location of the metaphase II spindle. To most oocytes, the regular operation of ICSI is safe. Of course, it will much more safe to use the Polscope during the injection. ( 2 ) The existing of the spindle may have a predictive value as to the opportunity of normal fertilization and high quality embryos. ( 3 ) The existing of the early cleavage may have a predictive value on the opportunity of high quality embryos. The existing of the spindle may have a...