Table 2 Association between female related physiological factors and the number of teeth

Menarche age (years)

under 14

481

19.8 ± 0.7

0.24

24.3 ± 0.5

0.10

15.0 ± 1.3

0.29

15–16

822

19.5 ± 0.4

24.0 ± 0.4

15.3 ± 0.6

17+

802

18.7 ± 0.4

23.6 ± 0.6

14.0 ± 0.6

0.68

0.10

0.18

Duration of menopause (years)

under 3

544

25.4 ± 0.3

<0.01

24.0 ± 0.6

0.07

–

0.15

4–9

792

22.0 ± 1.0

24.2 ± 0.3

14.1 ± 2.9

10–14

622

22.1 ± 0.4

24.1 ± 0.5

16.8 ± 1.6

15+

1,874

18.1 ± 0.4

23.6 ± 1.1

15.1 ± 0.3

<0.01

0.35

0.90

Number of pregnancies

under 3

1,049

20.6 ± 0.5

<0.01

24.4 ± 0.3

0.39

16.0 ± 0.8

0.97

4–6

1,964

19.3 ± 0.3

24.1 ± 0.2

14.5 ± 0.4

7+

960

18.9 ± 0.4

23.6 ± 0.6

15.3 ± 0.5

0.59

0.63

0.40

Age at first child’s birth (years)

under 19

411

17.5 ± 0.5

<0.01

23.2 ± 0.7

0.43

14.1 ± 0.9

<0.01

20–24

2,176

19.2 ± 0.3

23.8 ± 0.3

14.6 ± 0.4

25+

1,305

21.6 ± 0.3

24.4 ± 0.3

16.6 ± 0.6

<0.01

0.50

0.10

Duration of taking oral contraceptives (months)

Not taking

1,740

19.0 ± 0.3

<0.05

24.0 ± 0.3

0.18

14.5 ± 0.5

0.12

under 6

319

21.0 ± 0.7

24.0 ± 0.6

17.2 ± 1.7

7–18

212

20.9 ± 0.7

23.3 ± 0.9

16.3 ± 1.3

19+

1,698

19.6 ± 0.3

24.3 ± 0.3

15.1 ± 0.4

<0.01

0.08

0.48

Duration of taking female hormone drugs(years)

Not taking

1,903

18.8 ± 0.3

<0.01

23.7 ± 0.3

<0.01

14.3 ± 0.4

<0.01

under 1

304

24.1 ± 0.5

25.2 ± 0.3

20.3 ± 2.1

more than 1

1,771

19.7 ± 0.3

24.2 ± 0.3

15.2 ± 0.5

<0.01

0.07

0.64

Calcium intake

Q1

998

17.7 ± 0.4

<0.01

22.9 ± 0.5

0.11

13.2 ± 0.6

<0.05

Q2

998

20.0 ± 0.4

24.4 ± 0.3

15.8 ± 0.6

Q3

998

20.5 ± 0.4

24.0 ± 0.3

16.4 ± 0.6

Q4

998

20.2 ± 0.3

24.6 ± 0.3

15.2 ± 0.6

<0.05

0.18

0.55