Table 1.
Patients who had cryopreserved‐thawed embryo transfer in a natural or hormone‐replacement cycle
| Natural cycle | Hormone‐replacement cycle | |
|---|---|---|
| No. cycles | 720 | 136 |
| Age (years, mean ± SD) | 34.7 ± 3.4 | 34.5 ± 3.6 |
| Age range (years) | 24–44 | 25–44 |
| Average infertility period (months) | 42.6 ± 30.7 | 39.5 ± 30.8 |
| Mean number of embryos transferred | 1.58 ± 0.57 | 1.52 ± 0.54 |
| Number of transferred embryo (%) | ||
| 1 | 332 (46.1%) | 68 (50.0%) |
| 2 | 359 (49.9%) | 65 (47.8%) |
| 3 | 29 (4.0%) | 3 (2.2%) |
| Cycles of cleavage stage and blastocyst stage (%) | ||
| Cleavage stage | 149 (20.7%) | 29 (21.3%) |
| Blastocyst stage | 571 (79.3%) | 107 (78.7%) |
| Cycles of conventional IVF and ICSI cycles (%) | ||
| Conventional IVF | 412 (57.2%) | 81 (59.6%) |
| ICSI | 295 (41.0%) | 54 (39.7%) |
| Conventional IVF and ICSI | 13 (1.8%) | 1 (0.7%) |
| Cycles involving assisted hatching (%) | 568 (78.9%) | 104 (76.5%) |
| Endometrial thickness (mm) | 11.5 ± 3.7 | 10.9 ± 2.0 |
None of the differences between the two groups were statistically significant for any of the variables.
ICSI, intracytoplasmic sperm injection; IVF, in vitro fertilization.