Table 1.
General characteristics of included patients transferred with cleavage embryos
| Characteristic | Single cleavage embryo (864) | Two cleavage embryos (6045) | P | |||
|---|---|---|---|---|---|---|
| Fresh-ET (456) | Frozen-thawed ET (408) | P | Total (864) | |||
| Age (years) mean (SD) | 32.0 (4.6) | 36.3 (6.4) | < 0.001 | 34.0 (6.0) | 32.9 (5.6) | < 0.001 |
| Duration of infertility (years) median (IQR) | 3.0 (3.5) | 3.0 (4.2) | 0.320 | 3.0 (3.3) | 3.0 (3.0) | 0.01 |
| BMI (kg/m2) mean (SD) | 24.0 (3.3) | 24.4 (3.2) | 0.064 | 24.22 (3.27) | 24.0 (3.3) | 0.056 |
| Endometrial thickness (mm) (IQR) | 11.0 (2.9) | 9.0 (2.0) | < 0.001 | 10.3 (3.0) | 10.0 (3.0) | 0.464 |
| Transfer protocol n (%) | ||||||
| IVF/ICSI | 456 (100%) | – | – | 456 (52.8%) | 2736 (45.3%) | < 0.001 |
| FET | – | 408 (100%) | 408 (47.2%) | 3309 (54.7%) | ||
| Type of infertility n (%) | ||||||
| Primary | 186 (40.8%) | 124 (30.4%) | 0.001 | 310 (35.9%) | 2529 (41.8%) | 0.001 |
| Secondary | 270 (59.2%) | 284 (69.6%) | 554 64.1%) | 3516 (58.2%) | ||
| Causes of infertility n (%) | ||||||
| Male factors | 110 24.0%) | 61 (15.0%) | < 0.001 | 171 (19.8%) | 1212 (20.0%) | 0.100 |
| Pelvic and fallopian tube factors | 153 (33.6%) | 108 (26.5%) | 261 (30.2%) | 2004 (33.2%) | ||
| Ovulation failure | 43 (9.4%) | 69 (16.9%) | 112 (13.0%) | 680 (11.2%) | ||
| Other female factors | 32 (7.0%) | 58 (14.2%) | 90 (10.4%) | 495 (8.2%) | ||
| Both side factors | 91 (20.0%) | 91 (22.3%) | 182 (21.0%) | 1268 (21.0%) | ||
| Unexplained | 27 (6.0%) | 21 (5.1%) | 48 (5.6%) | 386 (6.4%) | ||
| Number of top quality embryo n (%) | ||||||
| 0 | 115 (25.2%) | 136 (33.3%) | 0.009 | 251 (31.9%) | 850 (15.0%) | < 0.001 |
| 1 | 341 (74.8%) | 272 (66.7%) | 613 (78.1%) | 1738 (31.9%) | ||
| 2 | – | – | – | 3457 (63.1%) | ||
Data are expressed as the means (SD) or number (percentage). “–” refers to absence of data