Table 2 Pregnancy and birth outcomes compared between the immediate and delayed FET groups. Data are presented as numbers (%)
| Â | Intention-to-treat analysis | Per-protocol analysis | ||||||
|---|---|---|---|---|---|---|---|---|
Immediate FET group | Delayed FET group | Relative risk (95% CI) | P-value | Immediate FET group | Delayed FET group | Relative risk (95% CI) | P-value | |
Subjects | 366 | 366 | Â | Â | 326 | 320 | Â | Â |
Positive pregnancy | 155 (42.3) | 159 (43.4) | 0.98 (0.83 to 1.15) | 0.765 | 154 (47.2) | 157 (49.1) | 0.96 (0.82 to 1.13) | 0.643 |
Embryo implantation | 157/620 (25.3) | 125/609 (20.5) | 1.23 (1.00 to 1.52) | 0.046 | 156/620 (25.2) | 123/609 (20.2) | 1.25 (1.01 to 1.53) | 0.038 |
Clinical pregnancy a | 137 (37.4) | 111 (30.3) | 1.23 (1.01 to 1.51) | 0.042 | 136 (41.7) | 109 (34.1) | 1.23 (1.00 to 1.50) | 0.045 |
Biochemical pregnancy loss | 18 (11.6) | 48 (30.2) | 0.39 (0.24 to 0.63) |  < 0.001 | 18 (11.7) | 48 (30.6) | 0.28 (0.23 to 0.63) |  < 0.001 |
Clinical pregnancy loss b | 15 (10.9) | 13 (11.7) | 0.94 (0.47 to 1.88) | 0.850 | 15 (11.0) | 12 (11.0) | 1.00 (0.49 to 2.05) | 0.996 |
Total pregnancy loss | 33 (21.3) | 61 (38.4) | 0.56 (0.39 to 0.80) | 0.001 | 33 (21.4) | 60 (38.2) | 0.56 (0.39 to 0.81) | 0.001 |
Ectopic pregnancy | 2 (1.3) | 5 (3.1) | 0.41 (0.08 to 2.08) | 0.448 | 2 (1.3) | 5 (3.2) | 0.40 (0.08 to 2.04) | 0.448 |
Multiple pregnancy | 18 (13.1) | 14 (12.6) | 1.04 (0.54 to 2.00) | 0.902 | 18 (13.2) | 14 (12.8) | 1.03 (0.54 to 1.98) | 0.928 |
Ongoing pregnancy | 122 (33.3) | 98 (26.8) | 1.25 (0.99 to 1.56) | 0.053 | 121 (37.1) | 97 (30.3) | 1.22 (0.99 to 1.52) | 0.067 |
Live birth | 120 (32.8) | 96 (26.2) | 1.25 (0.99 to 1.57) | 0.052 | 119 (36.5) | 96 (30.0) | 1.22 (0.98 to 1.52) | 0.079 |