Table II.
Characteristics of patients with pregnancy with HCG >100 IU/ml after FET according to endometrial preparation protocol.
| Total cycles | Artificial cycle (AC) | Natural cycle (NC) | Stimulated cycle (SC) | P | |
|---|---|---|---|---|---|
| Number of pregnancies with HCG >100 IU/ml | 3844 | 2214 | 812 | 818 | |
| Age (years), mean ± SD | 33.5 ± 4.3 | 33.3 ± 4.4 | 33.7 ± 4.3 | 33.8 ± 4.2 | 0.40 |
| BMI (kg/m2), mean ± SD | 21.9 ± 4.8 | 22.4 ± 4.5 | 21.4 ± 5.1 | 21.1 ± 5.6 | 0.01 |
| Smoking (%) | 879 (22.9) | 517 (23.4) | 188 (23.2) | 174 (21.3) | 0.50 |
| Ovulation disorder* (%) | 937 (24.4) | 682 (30.8) | 89 (11) | 166 (20.3) | 0.01 |
| History of early pregnancy loss (%) | 591 (13.4) | 335 (15.1) | 131 (16.1) | 125 (15.3) | 0.80 |
| History of childbirth (%) | 1919 (49.9) | 1137 (51.5) | 373 (48.4) | 409 (48.8) | 0.03 |
| Uterine disease (%) | 261 (6.8) | 152 (6.9) | 65 (8) | 44 (5.4) | 0.10 |
| Endometriosis (%) | 383 (10) | 228 (10.3) | 69 (8.5) | 86 (10.5) | 0.30 |
| Endometrial thickness (mm), mean ± SD | 9.3 ± 2.6 | 9 ± 2.8 | 9.9 ± 2.4 | 9.2 ± 2.2 | <0.01 |
| Number of embryos transferred, mean ± SD | 1.4 ± 0.5 | 1.4 ± 0.5 | 1.3 ± 0.5 | 1.5 ± 0.5 | 0.09 |
| Duration of freezing (days), mean ± SD | 363 ± 470 | 354 ± 467 | 382 ± 465 | 371 ± 484 | 0.60 |
*
Ovulation disorders include central anovulation, polycystic ovary syndrome and primary ovarian insufficiency.
FET, frozen embryo transfer.