Table 3 Pregnancy outcomes for NAC group versus control group—intention-to-treat analysis

Pregnancy outcomes (per cycle)

Biochemical pregnancy rate per cycles, %(n)

33.45% (95/284)

25.09% (70/279)

0.029

4.749

1.50(1.04, 2.16)

0.20

Clinical pregnancy rate per cycle, %(n)

30.99% (88/284)

23.30% (65/279)

0.040

4.204

1.48(1.02, 2.15)

0.18

Clinical pregnancy rate per cycle—strata 1 (BMI < 24), %(n)

31.05% (50/161)

25.00% (38/152)

0.234

1.419

1.35(0.82, 2.22)

0.08

Clinical pregnancy rate per cycle—strata 1 (BMI ≥ 24), %(n)

30.89% (38/123)

21.26% (27/127)

0.083

3.015

1.66(0.94, 2.93)

0.19

Cumulative clinical pregnancy (per patient)

 Cumulative clinical pregnancy rate per patient

77.88% (88/113)

58.04% (65/112)

0.001

10.175

2.55(1.42, 4.55)

0.68

 Cumulative clinical pregnancy rate—strata 1 (BMI < 24), %(n)

81.97% (50/61)

73.08% (38/52)

0.256

1.288

1.68(0.68, 4.10)

0.12

 Cumulative clinical pregnancies—strata 2 (BMI ≥ 24)

73.08% (38/52)

45.00% (27/60)

0.003

9.017

3.32(1.50, 7.36)

0.85

 Singleton pregnancy rate, %(n)

82.95% (73/88)

81.54% (53/65)

0.820

0.052

1.10(0.48, 2.55)

0.004

 Multiple pregnancy rate, %(n)

14.77% (13/88)

16.92% (11/65)

0.718

0.131

0.85(0.035, 2.04)

0.01

 Early miscarriage rate, %(n)

7.95% (7/88)

6.15% (4/65)

0.670

0.182

1.32(0.37, 4.71)

0.002

 Ectopic pregnancy rate, %(n)

2.27% (2/88)

1.54% (1/65)

1.000^$

-

1.49(0.13, 16.77)

-

 Cumulative ongoing pregnancy rate per patient

69.91% (79/113)

53.57% (60/112)

0.012

6.36

0.17(0.07, 2.55)

0.42