Table 1 Description of study population

Age (years)

35.49 ± 7.00

34.24 ± 7.53

34.88 ± 6.46

35.94 ± 6.86

Gravidity

1.45 ± 1.56

1.18 ± 1.31

1.39 ± 1.42

1.48 ± 1.46

Parity

0.58 ± 0.71

0.49 ± 0.63

0.63 ± 0.72

0.58 ± 0.75

Body mass index(kg/m²)

21.45 ± 3.35

21.49 ± 3.23

21.14 ± 3.01

21.85 ± 3.64

Age of first sexual(years) intercourse

21.77 ± 3.23

21.63 ± 3.11

21.69 ± 3.17

22.18 ± 3.31

Sexual age(years)

13.72 ± 6.85

12.61 ± 7.20

13.19 ± 6.82

13.76 ± 6.58

Number of sexual partners

2.92 ± 2.45

3.06 ± 2.32

2.96 ± 1.87

3.36 ± 2.64

Richness index^a

283.16 ± 214.11

301.13 ± 217.65

356.93 ± 280.61

282.15 ± 239.79

CHAO1 index^a

427.92 ± 301.70

465.17 ± 309.90

518.29 ± 372.63

429.60 ± 332.13

ACE index^a

449.03 ± 308.44

488.70 ± 320.63

540.30 ± 378.92

447.06 ± 343.05

Shannon index^a

1.32 ± 0.62

1.40 ± 0.59

1.57 ± 0.76

1.77 ± 0.84

Simpson index^a

0.47 ± 0.20

0.50 ± 0.20

0.54 ± 0.21

0.61 ± 0.21

Invsimpson index^a

2.46 ± 2.26

2.65 ± 1.81

3.20 ± 3.22

4.47 ± 5.75

Native place

 Beijing

72 (25.81%)

62 (26.61%)

34 (23.13%)

8 (24.24%)

 Others

207 (74.19%)

171 (73.39%)

113 (76.87%)

25 (75.76%)

Education

 Junior high school and below

21 (7.55%)

21 (9.01%)

19 (12.93%)

6 (18.18%)

 Junior high school to high school

59 (21.22%)

45 (19.31%)

45 (30.61%)

4 (12.12%)

 Bachelor degree or above

198 (71.22%)

167 (71.67%)

83 (56.46%)

23 (69.70%)

Family history of cancer

 No

189 (67.74%)

151 (64.81%)

94 (63.95%)

23 (69.70%)

 Yes

90 (32.26%)

82 (35.19%)

53 (36.05%)

10 (30.30%)

History of HPV infection

 No

162 (58.06%)

127 (54.51%)

79 (53.74%)

19 (57.58%)

 Yes

117 (41.94%)

106 (45.49%)

68 (46.26%)

14 (42.42%)

Contraceptive methods

 Condom

206 (73.84%)

176 (75.54%)

109 (74.15%)

22 (66.67%)

 Other methods or no contraception

73 (26.16%)

57 (24.46%)

38 (25.85%)

11 (33.33%)

HPV vaccine

 Unvaccinated

200 (71.68%)

168 (72.10%)

109 (74.15%)

28 (84.85%)

 Vaccinated

79 (28.32%)

65 (27.90%)

38 (25.85%)

5 (15.15%)

Smoking

 Non-smoking

252 (90.32%)

211 (90.56%)

132 (89.80%)

28 (84.85%)

 Smoking

27 (9.68%)

22 (9.44%)

15 (10.20%)

5 (15.15%)

TCT

 NSIL

212 (76.26%)

129 (55.36%)

76 (51.70%)

14 (42.42%)

 ASCUS

42 (15.11%)

55 (23.61%)

35 (23.81%)

5 (15.15%)

 LSIL

22 (7.91%)

46 (19.74%)

27 (18.37%)

7 (21.21%)

 ASC-H

2 (0.72%)

2 (0.86%)

4 (2.72%)

3 (9.09%)

 HSIL

0 (0.00%)

1 (0.43%)

5 (3.40%)

4 (12.12%)

Transformation zone (TZ)

 TZ-1

206 (73.84%)

180 (77.25%)

125 (85.03%)

27 (81.82%)

 TZ-2

36 (12.90%)

31 (13.30%)

17 (11.56%)

3 (9.09%)

 TZ-3

37 (13.26%)

22 (9.44%)

5 (3.40%)

3 (9.09%)

Colposcopic impression

 No signs of abnormalities

57 (20.43%)

45 (19.31%)

23 (15.65%)

3 (9.09%)

 LSIL

199 (71.33%)

152 (65.24%)

84 (57.14%)

4 (12.12%)

 HSIL

23 (8.24%)

36 (15.45%)

40 (27.21%)

26 (78.79%)