Table 1.
Comparison of basic clinical data and clinical outcomes among the three groups.
| Group D5 (n=5945) | Group D6(n=4094) | Group D7(n=137) | P valuea | P valueb | |
|---|---|---|---|---|---|
| Female age (years) | 32.4 ± 4.6 | 33.2 ± 5.0 | 33.4 ± 5.2 | 0.013 | 0.788 |
| Male age (years) | 33.3 ± 5.3 | 34.3 ± 5.9 | 34.4 ± 5.0 | 0.023 | 0.835 |
| Female body mass index (kg/m2) | 23.8 ± 3.3 | 23.8 ± 3.9 | 23.7 ± 3.1 | 0.878 | 0.875 |
| Infertility type (%) | 0.512 | 0.431 | |||
| Primary infertility | 2395 (40.3%) | 1626 (39.7%) | 59 (43.1%) | ||
| Secondary infertility | 3550 (59.7%) | 2468 (60.3%) | 78 (56.9%) | ||
| Main infertility cause (%) | <0.001 | <0.001 | |||
| Female | 3469 (58.4%) | 2134 (52.1%) | 46 (33.6%) | ||
| Male | 1039 (17.5%) | 944 (23.1%) | 67 (48.9%) | ||
| Mixed | 1109 (18.7%) | 741 (18.1%) | 24 (17.5%) | ||
| Other | 328 (5.5%) | 275 (6.7%) | 0 (0.0%) | ||
| Infertility duration (years) | 3.2 ± 2.6 | 3.4 ± 3.0 | 3.7 ± 3.1 | 0.023 | 0.318 |
| Basal FSH (IU/L) | 6.2 ± 2.3 | 5.2 ± 3.1 | 6.1 ± 2.2 | 0.520 | <0.001 |
| Endometrial preparation method | 0.004 | <0.001 | |||
| Artificial cycle | 2742 (46.1%) | 2671 (65.2%) | 45 (32.8%) | ||
| Natural cycle | 2190 (36.8%) | 944 (23.1%) | 68 (49.6%) | ||
| Stimulated cycle | 1013 (17.0%) | 479 (11.7%) | 24 (17.5%) | ||
| Average number of embryos transferred (per patient) | 1.193±0.395 | 1.311±0.463 | 1.314±0.466 | 0.003 | 0.947 |
| The number of embryos transferred (per patient) | <0.001 | 0.947 | |||
| 1 | 4797 (80.7%) | 2820 (68.9%) | 94 (68.6%) | ||
| 2 | 1148 (19.3%) | 1274 (31.1%) | 43 (31.4%) | ||
| Endometrial thickness (mm) | 9.3 ± 1.6 | 9.4 ± 1.6 | 9.4 ± 1.9 | 0.556 | 0.575 |
| Clinical pregnancy rate | 3741 (62.9%) | 2104 (51.4%) | 19 (13.9%) | <0.001 | <0.001 |
| Miscarriage rate | 681 (18.2%) | 434 (20.6%) | 9 (47.4%) | 0.001 | 0.004 |
| Live birth rate | 3014 (50.7%) | 1658 (40.5%) | 10 (7.3%) | <0.001 | <0.001 |
arepresents Group D7 compared with Group D5, brepresents Group D7 compared with Group D6; Group D5 represents the D5 FET cycle; Group D6 represents the D6 FET cycle; Group D7 represents the D7 FET cycle.