Table 1 Characteristics of FET cycles comparing endometrial patterns on cleavage-stage embryo transfer day
A (n = 9) | B (n = 41) | B-C (n = 30) | C (n = 58) | F/H/χ2 | P value | |
|---|---|---|---|---|---|---|
Age, years, mean (± SD) | 35.44 ± 7.62 | 31.39 ± 5.34 | 34.4 ± 7.51 | 34.38 ± 6.19 | 2.346 | 0.076 |
BMI, kg/m2, mean (± SD) | 22.49 ± 2.57 | 22.76 ± 3.63 | 24.33 ± 3.23 | 23.84 ± 3.41 | 1.704 | 0.169 |
Duration of infertility, years, median (25th, 75th percentile) | 4.00 (1.50, 7.75) | 3.00 (2.00, 4.00) | 2.50 (1.50, 4.13) | 3.00 (2.00, 5.13) | 1.732 | 0.528 |
Infertility type | ||||||
Primary infertility, n (%) | 4 (44.44%) | 25 (60.98%) | 17 (56.67%) | 30 (51.72%) | 1.284 | 0.733 |
Secondary infertility, n (%) | 5 (55.56%) | 16 (30.02%) | 13 (43.33%) | 28 (48.28%) | ||
Main infertility cause | ||||||
Non-severe male infertility, n (%) | 1 (11.11%) | 1 (2.44%) | 0 (00.00%) | 1 (1.72%) | 11.360 | 0.878 |
Severe male infertility, n (%) | 2 (22.22%) | 5 (12.30%) | 3 (10.00%) | 7 (12.07%) | ||
Diminished ovarian reserve | 1 (11.11%) | 4 (9.76%) | 5 (16.67%) | 9 (15.52%) | ||
Endometriosis, n (%), n (%) | 0 (00.00%) | 0 (00.00%) | 0 (00.00%) | 0 (00.00%) | ||
Ovulatory dysfunction, n (%) | 0 (00.00%) | 3 (7.32%) | 2 (6.67%) | 7 (12.07%) | ||
Tubal factor, n (%) | 3 (33.33%) | 20 (48.78%) | 13 (43.33%) | 25 (43.10%) | ||
Multiple female factors, n (%) | 2 (22.22%) | 5 (12.30%) | 4 (13.33%) | 7 (12.07%) | ||
Unexplained infertility, n (%) | 0 (00.00%) | 4 (9.76%)) | 3 (10.00%) | 2 (3.45%) | ||
Endometrial preparation protocol | ||||||
HRT | 6 (66.67%) | 31 (75.61%) | 22 (73.33%) | 33 (56.90%) | 4.567 | 0.206 |
GnRHa-HRT | 3 (33.33%) | 10 (24.39%) | 8 (26.67%) | 25 (43.10%) | ||
The day of progesterone initiation | ||||||
Endometrial thickness, mm, mean (± SD) | 9.37 ± 1.53 | 10.36 ± 1.62 | 10.26 ± 2.04 | 10.58 ± 2.43 | 0.923 | 0.432 |
Serum estrogen level, pmol/L, median (25th, 75th percentile) | 1971.0 (1594.0, 2072.0) | 1999.0 (1372.0, 5406.0) | 1738.0 (1178.0, 2750.0) | 2050.0 (1228.0, 6570.0) | 1.253 | 0.740 |
Serum progesterone level, pmol/L, median (25th, 75th percentile) | 1.37 (1.08, 1.69) | 1.42 (0.66, 1.89) | 1.44 (0.83, 2.16) | 1.05 (0.80, 1.62) | 2.840 | 0.417 |
The day of embryo transfer | ||||||
Endometrial thickness, mm, mean (± SD) | 10.06 ± 2.13 | 10.93 ± 3.04 | 10.5 ± 2.23 | 10.97 ± 2.4 | 0.511 | 0.675 |
Serum estrogen level, pmol/L, median (25th, 75th percentile) | 1680.0 (1441.0, 2284.0) | 1659.0 (1062.0, 2276.0) | 1695.5 (1196.0, 2268.0) | 1714.5 (1109.0, 2540.0) | 0.958 | 0.811 |
Serum progesterone level, pmol/L, median (25th – 75th percentile) | 25.05 (23.06, 26.88) | 26.46 (19.92, 33.42) | 32.71 (26.31, 39.23) | 29.81 (22.84, 36.11) | 5.066 | 0.167 |
The increase percentage of endometrial thickness on embryo transfer day compared with progesterone initiation day (%) | 5.88 (1.22, 19.77) | 5.83 (-6.31, 15.79) | 4.15 (-10.64, 15.91) | 5.39 (-8.09, 11.28) | 0.712 | 0.870 |
No. of embryos transferred | ||||||
1, n (%) | 2 (22.22%) | 4 (9.76%) | 8 (26.67%) | 15 (25.86%) | 4.537 | 0.209 |
2, n (%) | 7 (77.78%) | 37 (90.24%) | 22 (73.33%) | 43 (74.14%) | ||
Number of embryos transferred, n, mean (± SD) | 1.78 ± 0.44 | 1.90 ± 0.30 | 1.73 ± 0.45 | 1.74 ± 0.48 | 1.393 | 0.248 |
Grade of transferred embryos | ||||||
High-score embryo, number/total transferred embryos (%) | 13/16 (81.25%) | 72/78 (92.31%) | 44/52 (84.62%) | 94/101 (93.07%) | 4.651 | 0.199 |
Low-score embryo, number/total transferred embryos (%) | 3/16 (18.75%) | 6/78 (7.69%) | 8/52 (15.38%) | 7/101 (6.93%) | ||
Fertilization method of transferred embryos | ||||||
Embryos from IVF cycles/total transferred embryos (%) | 11/16 (68.75%) | 63/78 (80.77%) | 42/52 (80.77%) | 75/101 (74.26%) | 4.855 | 0.563 |
Embryos from ICSI cycles with ejaculated sperm/total transferred embryos (%) | 5/16 (31.25%) | 15/78 (19.23%) | 9/52 (17.31%) | 24/101 (23.76%) | ||
Embryos from ICSI cycles with sperm aspiration/total transferred embryos (%) | 0/16 (0.00%) | 0/78 (0.00%) | 1/52 (1.92%) | 2/101 (1.98%) | ||