Table 1 Characteristics of the participants

Age, years (mean ± SD)

31.5 ± 4.4

31.7 ± 4.7

0.749

Race, n (%)

0.317

  Han

345 (95.3)

357 (96.8)

  Minorities

17 (4.7)

12 (3.3)

BMI, kg/m² (mean ± SD)

22.5 ± 3.0

22.4 ± 3.1

0.556

Drinking history, n (%)

360 (99.5)

368 (99.7)

0.621

Years of infertility (years)

3 (2,6)

4 (2,6)

0.579

History of acupuncture, n (%)

15 (4.1)

10 (2.7)

0.289

Times of IVF-ET, n (%)

0.423

  1

185 (51.1)

196 (53.1)

  2–3

175 (48.3)

168 (45.5)

  ≥ 4

2 (0.6)

5 (1.4)

Causes of infertility, n (%)

0.824

  Gamete transport disorders

333 (92.0)

341 (92.4)

  Ovulation dysfunction

18 (5.0)

14 (3.8)

  Endometriosis

6 (1.7)

8 (2.2)

  Immunological infertility

5 (1.4)

6 (1.6)

Embryo, n (%)

0.771

  Fresh

183 (50.6)

190 (51.6)

  Cryopreserved

179 (49.5)

178 (48.4)

Comorbidities (before treatment), n (%)

0.953

  Hyperlipemia

2 (0.6)

0

  Hyperprolactinemia

2 (0.6)

3 (0.8)

  Hyperthyroidism

1 (0.3)

1 (0.3)

  Subhypothyroidism

2 (0.6)

2 (0.5)

  Hypothyroidism

3 (0.8)

1 (0.3)

Uterine cavity lesions, n (%)

0.833

  Submucous myoma

8 (2.2)

11 (3.0)

  Uterine mediastinum

2 (0.6)

0

Thin endometrium due to repeated curettages

1 (0.3)

3 (0.8)

Drugs, n (%)

  Combined drug therapy after inclusion

122 (33.7)

125 (33.9)

0.938

  Continue drug therapy after inclusion

24 (6.6)

34 (9.2)

0.219