Table 1 General data of all enrolled patients and relevant data in IVF/ICSI-ET cycles

Female age (y)

29.79 ± 3.72

BMI (kg/m²)

23.13 ± 3.24

Infertility duration (y)

3.27 ± 2.15

Infertility type

 Primary infertility

54.99% (1224/2226)

 Secondary infertility

45.01% (1002/2226)

Infertility factors

 Tubal factor

67.21% (1496/2226)

 Ovulatory obstacle

17.25% (384/2226)

 Reproductive tract

0.09% (2/2226)

 Endometriosis or adenomyosis

2.20% (49/2226)

 Male factors

8.22% (183/2226)

 Unexplained infertility

4.81% (107/2226)

 Basal FSH (mIU/mL)

7.09 ± 1.76

 Basal LH (mIU/mL)

6.17 ± 4.04

 Basal E₂ (pg/mL)

44.17 ± 51.57

 AFC (n)

20.54 ± 5.24

 Initiated Gn dose (IU)

129.27 ± 34.76

 FSH after GnRHa (mIU/mL)

3.46 ± 1.44

 LH after GnRHa (mIU/mL)

0.64 ± 0.38

 Total Gn dose (IU)

1966.18 ± 613.15

 Gn duration (y)

12.04 ± 2.39

 E₂ on hCG day (pg/mL)

2892.95 ± 1324.46

 LH on hCG day (mIU/mL)

1.61 ± 0.78

 P on hCG day (ng/mL)

0.64 ± 0.40

 Em (mm)

12.00 ± 2.54

 Total rLH dose (IU)

192.66 ± 102.63

 No. of of retrieved oocytes (n)

12.12 ± 3.69

 No. of MII oocytes (n)

10.60 ± 3.57

 MII rate

0.88 ± 0.13

 No. of fertilized oocytes (n)

9.99 ± 3.54

 No. of normally fertilized oocytes (2PN) (n)

9.06 ± 3.37

 2PN rate

0.91 ± 0.11

 No. of available embryos (n)

5.17 ± 2.47

 Available embryo rate

0.59 ± 0.21

 No. of transferred embryos (n)

1.56 ± 0.50

Type of transferred embryo

 cleavage-stage embryo

81.45% (1813/2226)

 blastocyst

18.55% (413/2226)

 No. of implanted embryos (n)

1.29 ± 0.48

 OHSS rate

8.221% (183/2226)

 Clinical pregnancy rate

71.29% (1587/2226)

 cleavage-stage embryo transfer

70.49% (1278/1813)

 blastocyst transfer

74.82% (309/413)

 Early miscarriage rate

7.18% (114/1587)

 cleavage-stage embryo transfer

7.04% (90/1278)

 blastocyst transfer

7.77% (24/209)

 Live birth rate

63.16% (1406/2226)

 cleavage-stage embryo transfer

62.49% (1133/1813)

 blastocyst transfer

66.10% (273/413)