Table 1.
Outcome of fertilization and embryo development between fresh and vitrified oocytes
| Fresh | Vitrified | p value | |
|---|---|---|---|
| Number of stimulations | 1.0 | 1.8 | |
| COCs | 8.7 ± 6.6 | 11.8 ± 6.0 | < 0.0001 |
| MII | 6.7 ± 5.0 | 8.5 ± 4.0 | 0.001 |
| MII injected | 6.6 ± 4.8 | 7.4 ± 3.8 (87.5% survival rate) | 0.097 |
| Fertilization rate | 81% | 75% | 0.036 |
| Normal fertilization | 5.3 ± 4.2 | 5.5 ± 3.0 | 0.642 |
| EQ 1 rate on day 3 | 338 (67.6%) | 275 (53%) | < 0.0001 |
| EQ 2 rate on day 3 | 72 (14.4%) | 84 (16.2%) | |
| EQ 3 rate on day 3 | 65 (13%) | 95 (18.3%) | |
| EQ 4 rate on day 3 | 25 (5.0%) | 65 (12.5%) | |
| EQ on day 5 A | 35 (11.9%) | 17 (8.1%) | 0.171 |
| EQ on day 5 B | 135 (45.9%) | 92 (43.8%) | |
| EQ on day 5 C | 113 (38.4%) | 97 (46.2%) | |
| EQ on day 5 D | 11 (3.7%) | 4 (1.9%) | |
| number of embryos cultured to D5 | 5.3 ± 4.1 | 5.3 ± 3.0 | 0.941 |
| number of blastocysts D5 | 3.1 ± 2.9 | 2.2 ± 1.8 | 0.005 |
| Blastulation rate | 62% ± 29 | 44% ± 31 | < 0.0001 |
Results are expressed as mean ± SD. SD, standard deviation. t test and chi-squared test for categorical data
COCs, cumulus oocytes complex; MII, mature oocyte; EQ, embryo quality
EQ on day 3: EQ 1—excellent; EQ 2—good; EQ 3—moderate; or EQ 4—poor
EQ on day 5: A—excellent; B—good; C—moderate; D—poor