Table 3.

Oocyte and embryo developmental parameters

Parameter	Low proportion	Middle proportion	High proportion	P value
Total number of COCs	808	898	720	–
Grades of COCs
Oocyte maturation rate*	80.60 %	84.38 %	91.49 %	<0.001
Normal fertilization rate	70.05 %	70.58 %	72.56 %	0.89
Abnormal fertilization rate*	6.51 %	6.62 %	12.13 %	0.036
Cleavage rate*	89.80 %	89.23 %	78.08 %	0.028
Number of transferable embryos*	6.46 ± 2.82	5.50 ± 1.18	4.34 ± 1.21	0.027
High-quality embryo rate*	60.19 %	46.67 %	41.93 %	0.039
Implantation rate*	41.41 %	31.58 %	29.27 %	0.042
Pregnancy rate*	56.60 %	48.33 %	40.74 %	0.036

The variance analysis and chi-square analysis were used for data comparisons. * P < 0.05, there were significant differences among the three groups