Female age at oocyte retrieval (y) |
30.58 ± 4.91 |
0.92 (0.91, 0.92) |
<0.001 |
Female age at embryo transfer (y) |
31.03 ± 4.84 |
0.92 (0.91, 0.92) |
<0.001 |
Infertility duration (y) |
3.46 ± 2.89 |
0.97 (0.95, 0.98) |
<0.001 |
BMI (kg/m2) |
|
|
|
<18.5 (n, %) |
862 (9.40%) |
Reference |
|
18.5-25 (n, %) |
6740 (73.52%) |
0.96 (0.83, 1.10) |
0.553 |
>25 (n, %) |
3065 (33.44%) |
0.77 (0.65, 0.91) |
0.003 |
AFC (n) |
12.63 ± 5.98 |
1.05 (1.04, 1.06) |
<0.001 |
No. of oocyte retrieved (n) |
13.48 ± 7.47 |
1.05 (1.04, 1.05) |
<0.001 |
Fertilization type (n, %) |
|
|
|
IVF |
6829 (73.62%) |
Reference |
|
ICSI |
2191 (23.62%) |
1.08 (0.98, 1.19) |
0.106 |
IVF+ICSI |
256 (2.76%) |
1.04 (0.81, 1.34) |
0.749 |
Infertility type (n, %) |
|
|
|
Primary infertility |
4878 (53.08%) |
Reference |
|
Secondary infertility |
4312 (46.92%) |
0.71 (0.65, 0.77) |
<0.001 |
Protocol in the fresh cycle (n, %) |
|
|
|
Agonist |
6853 (74.10%) |
Reference |
|
Antagonist |
1844 (19.94%) |
0.57 (0.52, 0.64) |
<0.001 |
Other |
551 (5.96%) |
0.38 (0.32, 0.46) |
<0.001 |
Previous fresh embryo transfer (n, %) |
4599(47.23) |
0.81(0.73,0.96) |
0.082 |
Clinical pregnancy in fresh cycles (n, %) |
2561(55.69) |
0.92(0.83,1.01) |
0.097 |
Single blastocyst transfer (n, %) |
|
|
|
No |
7825 (80.40) |
Reference |
|
Yes |
1908 (19.60) |
0.74 (0.67, 0.82) |
<0.001 |
Endometrial thickness on the day of P administration (mm) |
10.15 ± 1.66 |
1.07 (1.04, 1.09) |
<0.001 |
Triple-line endometrial pattern (n, %) |
|
|
|
A |
1414 (14.55) |
Reference |
|
B |
7662 (78.84) |
0.91 (0.81, 1.02) |
0.102 |
C |
643 (6.62) |
0.63 (0.52, 0.76) |
<0.001 |
Type of embryo transferred (n, %) |
|
|
|
Cleavage stage |
4201 (43.16) |
Reference |
|
Blastocyst stage |
5532 (56.84) |
1.61 (1.48, 1.74) |
<0.001 |
No. of transferred embryos (n, %) |
|
|
|
1 |
2587 (26.58) |
Reference |
|
2 |
7023 (72.16) |
1.80 (1.64, 1.97) |
<0.001 |
3 |
123 (1.26) |
0.74 (0.51, 1.09) |
0.129 |
No. of transferrable embryos (n) |
7.08 ± 4.34 |
1.10 (1.08, 1.11) |
<0.001 |
No. of good quality embryos transferred (n, %) |
|
|
|
0 |
3430 (35.24) |
Reference |
|
1 |
3643 (37.43) |
1.68 (1.53, 1.85) |
<0.001 |
2 |
2659 (27.30) |
2.89 (2.60, 3.22) |
<0.001 |