Table 2.
Embryo transfer (ET) characteristics by the study group (ET-MII, ET-MIX, ET-IVMC)
| ET-MII (n = 3579) | ET-MIX (n = 264) | ET-IVMC (n = 90) | p-value1 | |
|---|---|---|---|---|
| Origin of sperm; n (%) | ||||
| Partner | 2002 (55.9) | 133 (50.4) | 60 (66.7) | 0.018 |
| Donor | 1577 (43.7) | 131 (49.6) | 30 (33.3) | |
| Status of sperm; n (%) | ||||
| Fresh | 1347 (37.7) | 90 (34.1) | 35 (38.9) | 0.48 |
| Frozen | 2228 (62.3) | 174 (65.9) | 55 (61.1) | |
| ET day; n (%) | ||||
| D2–4 | 3442 (96.2) | 258 (97.7) | 89 (98.9) | 0.18 |
| D5 | 137 (3.8) | 6 (2.3) | 1 (1.1) | |
| Transferred embryos; n (%) | < 0.001 | |||
| 1 | 747 (20.9) | 0 (0.0)* | 65 (72.2)* | |
| 2 | 2182 (61.0) | 164 (62.1) | 22 (24.4)* | |
| 3 | 650 (18.2) | 100 (37.9)* | 3 (3.3)* | |
| Mean embryo quality at D2–D3 of transferred embryos; mean (SD) | 7.7 (1.3) | 7.6 (1.3) | 6.8 (1.2)* | < 0.001 |
COC cumulus-oophorus complex, GV germinal vesicle, ICSI intracytoplasmic injection, IVMC in vitro meiotic completion, MI metaphase I oocytes (immature post-GVBD oocytes), MII metaphase II oocytes (mature oocytes), n number of cycles, OPU oocyte pick-up, SD standard deviation
*Statistically siginificant difference after pairwise comparison with Bonferroni’s correction between this group and ICSI-MII
1One-way ANOVA or Pearson’s Chi2 test, as appropriate