Table 3.
Reproductive Outcomes After FET According To The Type Of Endometrial Preparation Treatments
| Characteristics | Letrozole (n=1569) | HMG (n=1827) | Letrozole+HMG (n=2505) | P-Valuea | P-Valueb | P-Valuec |
|---|---|---|---|---|---|---|
| Number of FET | 1569 | 1827 | 2505 | |||
| Number of thawed embryos | 3022 | 3476 | 4715 | |||
| Number of viable embryos after thawed | 2986 | 3441 | 4687 | |||
| Developmental stage at cryopreservation | ||||||
| Cleavage stage (Day 3 or 4) | 2619(87.71%) | 3043(88.42%) | 2203(87.93%) | 0.196 | 0.295 | 0.412 |
| Blastocyst stage (Day 5) | 367(12.29%) | 398(11.58%) | 302(12.07%) | |||
| Embryo quality | ||||||
| Grade I | 649(21.73%) | 690(20.06%) | 523(20.86%) | 0.245 | 0.076 | 0.091 |
| Grade II | 2332(78.09%) | 2746(79.79%) | 1970(78.66%) | |||
| Grade III | 5(0.18%) | 5(0.15%) | 12(0.48%) | |||
| Number of embryos transferred | ||||||
| 1 | 194(6.49%) | 221(6.42%) | 285(6.08%) | 0.472 | 0.279 | 0.246 |
| 2 | 2792(93.51%) | 3220(93.58) | 4402(99.92%) | |||
| Clinical pregnancy rate per transfer (%) | 52.07% (817/1569) | 47.02% (859/1827) | 52.26% (1309/2505) | 0.047 | 0.037 | 0.486 |
| Implantation rate (%) | 34.36% (1026/2986) | 31.76% (1086/3441) | 34.24% (1605/4687) | 0.048 | 0.036 | 0.481 |
| Miscarriage rate (%) | 10.53% (86/817) | 14.78% (127/859) | 14.13% (185/1309) | 0.013 | 0.381 | 0.018 |
| Multiple pregnancy rate (%) | 25.58% (209/817) | 26.43% (227/859) | 22.61% (296/1309) | 0.402 | 0.063 | 0.121 |
| Ectopic pregnancy rate (%) | 0.97% (5/833) | 1.83% (16/875) | 1.58% (21/1330) | 0.018 | 0.392 | 0.031 |
| Intrauterine and ectopic pregnancy rate (%) | 0.36% (3/833) | 0.80%(7/875) | 0.38% (5/1330) | 0.194 | 0.161 | 0.629 |
| Ongoing pregnant rate per transfer (%) | 47.61% (747/1569) | 41.32%(755/1827) | 47.27% (1184/2505) | 0.012 | 0.009 | 0.461 |
| Live birth rate (%) | 46.59% (731/1569) | 39.96%(730/1827) | 44.87% (1124/2505) | 0.008 | 0.022 | 0.265 |
Notes: aLetrozole vs HMG; bHMG vs letrozole+HMG; cLetrozole vs letrozole+HMG. Bold values represent statistical significance.