Table 2.
Embryo status and pregnancy outcomes-median (P25, P75).
| Characteristics | Before PSM | After PSM | ||||||
|---|---|---|---|---|---|---|---|---|
| Total (n = 11,491) | Group A (n = 2,371) | Group B (n = 9,120) | p | Total (n = 9,424) | Group A (n = 2,365) | Group B (n = 7,059) | p | |
| Overall pregnancy status | ||||||||
| Live birth | 5,563 (48.4%) | 1,119 (47.2%) | 4,444 (48.7%) | 0.191 | 4,603 (48.8%) | 1,117 (47.2%) | 3,486 (49.4%) | 0.074 |
| Premature birth | 2,040 (17.8%) | 417 (17.6%) | 1,623 (17.8%) | 0.573 | 1,675 (17.8%) | 416 (17.6%) | 1,259 (17.8%) | 0.240 |
| Full-term delivery | 3,494 (30.4%) | 696 (29.4%) | 2,798 (30.7%) | 0.575 | 2,902 (30.8%) | 695 (29.4%) | 2,207 (31.3%) | 0.290 |
| Biochemical pregnancy (14 day) | 7,754 (67.5%) | 1,581 (66.7%) | 6,173 (67.7%) | 0.365 | 6,386 (67.8%) | 1,576 (66.6%) | 4,810 (68.1%) | 0.185 |
| Clinical pregnancy (28 days) | 6,365 (55.4%) | 1,300 (54.8%) | 5,065 (55.5%) | 0.552 | 5,263 (55.8%) | 1,296 (54.8%) | 3,967 (56.2%) | 0.245 |
| Miscarriage | 2,192 (19.07%) | 463 (19.5%) | 1,729 (19.0%) | 0.841 | 1,783 (18.9%) | 459 (19.4%) | 1,324 (18.8%) | 0.862 |
| Fresh embryo transfer | ||||||||
| Live birth | 1,103 (41.3%) | 218 (38.3%) | 893 (42.1%) | 0.107 | 979 (43.4%) | 217 (38.4%） | 762 (45.2%) | 0.107 |
| Biochemical pregnancy (14 days) | 1,565 (58.1%) | 317 (55.7%) | 1,248 (58.8%) | 0.187 | 1,346 (59.8%) | 316 (55.9%） | 1,030 (58.1%) | 0.097 |
| Clinical pregnancy (28 days) | 1,281 (47.6%) | 256 (45.0%) | 1,025 (48.3%) | 0.163 | 1,123 (49.8%） | 258 (45.7%） | 865 (49.3%) | 0.163 |
| Miscarriage | 454 (16.8%) | 99 (17.4%) | 355 (16.7%) | 0.562 | 396 (17.5%) | 99 (17.5%) | 297 (17.6%) | 0.834 |
| Fresh embryo transfer rate (%) | 23.42 | 24 | 23.27 | 0.317 | 23.38 | 23.27 | 23.4 | 0.532 |
| Frozen embryo transfer (FET) | ||||||||
| Live birth | 4,425 (50.2%) | 901 (50.0%) | 3,551 (50.8%) | 0.654 | 3,624 (50.5%) | 900 (50.0%） | 2,724 (50.6%) | 0.654 |
| Biochemical Pregnancy (14 days) | 6,189 (70.3%) | 1,264 (70.1%) | 4,925 (70.4%) | 0.840 | 5,040 (70.2%) | 1,260 (70.0%） | 3,780 (70.3%) | 0.824 |
| Clinical Pregnancy (28 days) | 5,084 (57.8%) | 1,044 (57.9%) | 4,040 (57.7%) | 0.880 | 4,140 (57.7%) | 1,038 (57.7%） | 3,102 (57.7%) | 0.874 |
| Miscarriage | 1,738 (19.6%) | 364 (20.1%) | 1,374 (19.6%) | 0.991 | 1,387 (19.3%) | 360 (20.0%) | 1,027 (19.1%) | 0.762 |
| Oocyte and embryo status | ||||||||
| MII oocytes (mature eggs) | 12.00 (8.00, 17.00) | 12.00 (8.00, 17.00) | 12.00 (8.00, 17.00) | 0.726 | 12.00 (8.00, 17.00) | 12.00 (8.00, 17.00) | 12.00 (8.00, 17.00) | 0.059 |
| Number of 2PN embryo(s) | 9.00 (5.00, 13.00) | 9.00 (6.00, 13.00) | 9.00 (5.00, 13.00) | 0.231 | 9.00 (5.00, 13.00) | 9.00 (6.00, 13.00) | 8.00 (5.00, 13.00) | 0.011 |
| Number of usable Embryos (D3) | 8.00 (4.00, 12.00) | 7.00 (4.00, 12.00) | 8.00 (4.00, 12.00) | 0.909 | 7.00 (4.00, 12.00) | 7.00 (4.00, 12.00) | 7.00 (4.00, 12.00) | 0.143 |
| Cleavage-stage Embryos of good quality | 3.00 (1.00, 6.00) | 3.00 (1.00, 6.00) | 3.00 (1.00, 6.00) | 0.190 | 3.00 (1.00, 6.00) | 3.00 (1.00, 6.00) | 3.00 (1.00, 6.00) | 0.300 |
| Blastocysts of good quality | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | <0.001 | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | 0.00 [0.00, 0.00] | <0.001 |
| Oocyte fertilization rate (%) | 78.57 (66.67, 87.50) | 77.78 (66.67) 87.50) | 80.00 (66.67, 87.50) | 0.012 | 78.89 (66.67, 87.91) | 77.78 (66.67) 87.55) | 79.98 (66.67, 87.43) | 0.094 |