TABLE 1.
Maternal and treatment characteristics by group of embryo transfer.
| Demographics | SET-GQE (n = 2991) | SET-PQE (n = 510) | DET-2GQE (n = 20,980) | DET-GQE+PQE (n = 1807) | DET-2PQE (n = 388) | P-value |
| Patients with eSET or eDET | 1266 (42.33) | 170 (33.33) | 16,135(76.91) | 971 (53.74) | 195 (50.26) | |
| Maternal age(y), n (%) | <0.001 | |||||
| ≤30 | 1080 (36.11) | 157 (30.78) | 9793 (46.68) | 686 (37.96) | 144 (37.11) | |
| 31–34 | 866 (28.95) | 164 (32.16) | 6521 (31.08) | 553 (30.60) | 117 (30.15) | |
| ≥35 | 1045 (34.94) | 189 (37.06) | 4666 (22.24) | 568 (31.43) | 127 (32.73) | |
| Type of infertility, n (%) | 0.271 | |||||
| Primary infertility | 1599 (53.46) | 264 (51.76) | 11,370(54.19) | 958 (53.02) | 193 (49.74) | |
| Second infertility | 1392 (46.54) | 246 (48.24) | 9610 (45.81) | 849 (46.98) | 195 (50.26) | |
| Parity, n (%) | <0.001 | |||||
| Nulliparous | 2577 (86.16) | 421 (82.55) | 18,862(89.90) | 1568 (86.77) | 330 (85.05) | |
| Pluriparous | 414 (13.84) | 89 (17.45) | 2118 (10.10) | 239 (13.23) | 58 (14.95) | |
| Duration of infertility, mean ± SD | 3.95 ± 3.07 | 4.09 ± 3.10 | 3.72 ± 2.71 | 4.02 ± 2.91 | 4.20 ± 3.02 | <0.001 |
| Infertility causes, n (%) | 0.008 | |||||
| Female factor | 1816 (60.72) | 294 (57.65) | 12,725(60.65) | 1054 (58.33) | 241 (62.11) | |
| Male factor | 282 (9.43) | 49 (9.61) | 2281 (10.87) | 194 (10.74) | 44 (11.34) | |
| Combined factor | 631 (21.10) | 102 (20.00) | 4219 (20.11) | 377 (20.86) | 70 (18.04) | |
| Unexplained | 262 (8.76) | 65 (12.75) | 1755 (8.37) | 182 (10.07) | 33 (8.51) | |
| Stage of embryo development | <0.001 | |||||
| Cleavage-stage embryo | 2235 (74.72) | 148 (29.02) | 20,461(97.53) | 1541 (85.28) | 228 (58.76) | |
| Blastocyst | 756 (25.28) | 362 (70.98) | 519 (2.47) | 266 (14.72) | 160 (41.24) |
SET, single embryo transfer; DET, double embryos transfer; GQE, good quality embryo; PQE, poor quality embryo; FET: frozen-thawed embryo transfer; eSET, elective SET; eDET, elective DET.