Table 4 Factors influencing the live birth rate after first embryo transfer after in vitro maturation

 Age, years^a

28.1 ± 3.5

29.1 ± 3.5

0.94 (0.90, 0.98)

0.004

0.97 (0.93, 1.02)

0.254

 Body mass index, kg/m^2a

21.5 ± 2.8

22.0 ± 3.2

0.94 (0.90, 0.99)

0.019

0.95 (0.90, 1.00)

0.06

 Anti-Müllerian hormone, ng/mL^a

12.5 ± 3.6

12.2 ± 3.6

1.02 (0.98, 1.06)

0.304

–

–

 Antral follicle count – n

34.3±17.9

34.4±18.5

1.00 (0.99, 1.01)

0.96

–

–

 Follicle-stimulating hormone, IU/mL

8.6 ± 1.9

8.5 ± 1.8

1.03 (0.95, 1.11)

0.524

–

–

 Progesterone, ng/mL

0.8 ± 1.9

0.7 ± 1.8

1.01 (0.93, 1.09)

0.761

–

–

 Luteinizing hormone, IU/L

14.3 ± 6.9

13.5 ± 6.7

1.02 (1.00, 1.04)

0.105

 Free testosterone index

4.5 ± 5.6

4.6 ± 5.2

1.00 (0.97, 1.02)

0.786

–

–

  Amenorrhea

15 (5.4)

33 (5.5)

Ref

–

–

  Oligomenorrhea

256 (92.4)

551 (92.4)

1.02 (0.56, 1.97)

0.946

–

–

  Regular

6 (2.2)

12 (2.0)

1.10 (0.33, 3.43)

0.871

–

–

  Both ovaries

228 (82.3)

488 (81.9)

Ref

–

–

  One ovary

49 (17.7)

108 (18.1)

0.97 (0.67, 1.41)

0.88

–

–

 Duration of infertility, years^a

3.3 ± 2.3

3.8 ± 2.7

0.92 (0.86, 0.98)

0.011

0.95 (0.89, 1.02)

0.161

  Primary

229 (82.7)

479 (80.4)

Ref

–

–

  Secondary

48 (17.3)

117 (19.6)

0.86 (0.59, 1.24)

0.419

–

–

  1

259 (93.5)

514 (86.2)

Ref

–

–

  2

11 (4.0)

64 (10.7)

0.34 (0.17, 0.63)

0.001

0.60 (0.32, 1.09)

0.105^c

  3

7 (2.5)

18 (3.0)

0.77 (0.30, 1.80)

0.566

–

–

  Tubal factors

3 (1.1)

14 (2.3)

Ref

–

–

  Male factors

2 (0.7)

11 (1.8)

0.85 (0.10, 6.01)

0.869

–

–

  Ovulation induction failure

267 (96.4)

550 (92.3)

2.27 (0.73, 9.89)

0.202

1.92 (0.92, 4.38)

0.097

  Previous OHSS with COH

3 (1.1)

14 (2.3)

1.00 (0.16, 6.24)

0.99

–

–

  Others

2 (0.7)

7 (1.2)

1.33 (0.15, 9.99)

0.779

–

–

 Number of oocytes retrieved^a

15.6 ± 8.4

14.7 ± 9.1

1.01 (0.99, 1.03)

0.182

0.98 (0.95, 1.01)

0.286

 Number of mature oocytes after IVM^a

9.1 ± 5.0

8.5 ± 5.3

1.02 (0.99, 1.05)

0.109

0.97 (0.92, 1.02)

0.212

 Number of embryos available for transfer^a

6.8 ± 3.6

5.7 ± 3.6

1.09 (1.05, 1.13)

< 0.001

1.14 (1.07, 1.22)

< 0.001

 Mean number of embryos transferred^a

2.6 ± 0.5

2.5 ± 0.6

1.55 (1.20, 2.01);

0.001

  1 embryo transferred

2 (0.7)

34 (5.7)

0.14 (0.02, 0.47)

0.008

0.20 (0.03, 0.69)

0.032

  2 embryos transferred

104 (37.5)

247 (41.4)

Ref

–

Ref

–

  3 embryos transferred

171 (61.7)

315 (52.9)

1.29 (0.96, 1.73)

0.092

1.25 (0.92, 1.69)

0.152

  Fresh

263 (94.9)

560 (94.0)

Ref

–

–

  Freeze-only

14 (5.1)

36 (6.0)

0.83 (0.43, 1.53)

0.56

–

–