Table 2 Relationship between reproductive history and DMFT index based on Negative binomial regression analysis

Frequency of pregnancy

4 ≤

1.34

1.21–1.48

< 0.001

1.07

0.96–1.18

0.21

1.13

1.02–1.26

0.02

1.12

1.01–1.24

0.04

3

1.04

0.93–1.15

0.49

1.07

0.96–1.19

0.2

1.11

0.99–1.23

0.07

1.09

0.98–1.22

0.10

2

0.94

0.84–1.05

0.27

1.05

0.94–1.17

0.34

1.08

0.97–1.21

0.16

1.07

0.96–1.19

0.21

1

0.9

0.78–1.04

0.18

1

0.87–1.16

0.96

1.01

0.87–1.16

0.95

1

1.86–1.16

0.99

0

Age at the onset of menstrual (years)

Early (12>)

1.06

0.98–1.16

0.15

0.99

0.91–1.08

0.91

1.01

0.93–1.09

0.84

1.01

0.93–1.09

0.86

Late (14<)

1.12

1.07–1.18

< 0.001

1.01

0.96–1.06

0.77

1.02

0.97–1.07

0.34

1.03

0.98–1.08

0.25

Normal (12–14)

Age at the onset of menopause (years)

Precursor (< 40)

0.95

0.83–1.1

0.51

0.98

0.85–1.14

0.83

0.98

0.85–1.13

0.81

0.98

0.85–1.13

0.81

Early (40–45)

1

0.93–1.08

0.99

1

0.93–1.08

0.95

1.01

0.94–1.09

0.77

1.01

0.94–1.09

0.75

Normal (> 45)

Age at first pregnancy (years)

40–49

0.95

0.65–1.39

0.78

0.89

0.61–32/1

0.58

0.9

0.61–1.32

0.59

0.9

0.62–1.32

0.6

30–39

0.93

0.83–1.03

0.17

0.98

0.88–1.09

0.75

0.96

0.86–1.08

0.51

0.97

0.86–1.08

0.53

10–19

1.1

1.05–1.16

< 0.001

1.01

0.96–1.06

0.71

1.01

0.97–1.07

0.55

1.01

0.96–1.06

0.76

20–29