Skip to main content

Table 3 Association of preterm birth and smoking with maternal coronary heart disease (n = 1,968)

From: Preterm birth and future risk of maternal cardiovascular disease – is the association independent of smoking during pregnancy?

 

Univariate

Multivariate 1

Multivariate 2

 

HR

95 % CI

HR

95 % CI

HR

95 % CI

CHD

         

Term birth

Ref

  

Ref

  

Ref

  

Any preterm birth

2.01

1.75

2.30

1.73

1.50

1.99

1.61

1.39

1.85

Preterm birth by severity

         

Late preterm birth

1.79

1.50

2.15

1.59

1.33

1.90

1.49

1.24

1.78

Moderately preterm birth

2.37

1.79

3.14

2.07

1.56

2.75

1.89

1.43

2.51

Extremely preterm birth

2.30

1.77

2.98

1.86

1.39

2.48

1.72

1.29

2.29

Preterm birth by onset

         

Spontaneous preterm birth

1.78

1.50

2.10

1.67

1.41

1.97

1.53

1.29

1.81

Indicated preterm birth

2.53

2.05

3.13

1.86

1.48

2.32

1.77

1.41

2.21

Preterm birth by number

         

1 preterm birth

1.88

1.63

2.17

1.65

1.43

1.92

1.54

1.33

1.79

≥2 preterm births

3.64

2.55

5.19

2.58

1.79

3.71

2.31

1.61

3.33

Smokinga

         

Never smoking during pregnancy

Ref

     

Ref

  

Smoking before last pregnancy

1.97

1.58

2.47

   

1.49

1.19

1.87

Smoking during last pregnancy

2.37

2.16

2.60

   

2.13

1.92

2.35

  1. Multivariate 1: Preterm birth adjusted for maternal age at delivery, country of birth, socioeconomic status, number of births, SGA, pregestational and gestational diabetes
  2. Multivariate 2: Variables in Multivariate 1 + maternal smoking during pregnancy
  3. a: Multivariate 2 adjusted for any preterm birth