Table 2. Developmental potentials of oocytes and clinical outcomes of embryo transfer in case and control groups.
  Control group Case group ORa CIa
Numbers of ROa 5.2±3.5 4.4±4.2    
Numbers of FOa 3.8±2.6 2.8±2.5b    
Numbers of CEa 3.4±2.5 2.5±2.2b    
Numbers of SCEa 1.9±1.6 1.1±1.2c    
Fertilization rate
(total numbers of FO/ total numbers of RO)
72% (195/271) 63%d (144/227) 0.676 0.464-0.986
Development rate to SCE from RO
(total numbers of SCE/ total numbers of RO)
36% (98/271) 25%e (56/227) 0.578 0.392-0.853
Development rate to SCE from FO
(total numbers of SCE/ total numbers of FO)
50% (98/195) 39%d (56/144) 0.630 0.407-0.974
Development rate to SCE from CE
(total numbers of SCE/ total numbers of CE)
55% (98/177) 43%d (56/130) 0.610 0.387-0.962
Cycles of ETa (cryopreserved + fresh) 93 cycles 66 cycles        
Embryos transferred per ET cycle 1.5±0.7 1.3±0.5    
% Clinical pregnancies per ET cycle 20.4% 19/93 7.6%d 5/66 0.319 0.117-0.877
% Ongoing pregnancies per ET cycle 15.1% 14/93 7.6% 5/66    
% Live deliveries per ET cycle 14.0% 13/93 1.5%d 1/66 0.095 0.016-0.585

a RO, retrieved oocytes; FO, fertilized oocytes; CE, cleaving embryos; SCE, superior cleaving embryos; ET, embryo transfer; OR, odds ratio; CI, confidence interval.
b p<0.05 vs. control group, Mann-Whitney U test
c p<0.01 vs. control group, Mann-Whitney U test
d p<0.05 vs. control group, Chi-squared test
e p<0.01 vs. control group, Chi-squared test