Table 4 Logistic regressions of breastfeeding measures and demographic and socioeconomic characteristics. (Data from 2014 to 2018)

Maternal-based characteristics

 Age at delivery (year)

  < 25 (Ref.)

1.00

1.00

1.00

1.00

  25–34

0.92

0.75

1.13

0.44

0.93

0.81

1.06

0.29

1.10

0.98

1.25

0.12

1.51

1.08

2.12

0.02

   ≥ 35

0.87

0.67

1.14

0.32

0.81

0.68

0.97

0.02

0.98

0.83

1.15

0.78

1.58

1.03

2.41

0.04

 Educational level

  Illiterate or primary school (Ref.)

1.00

1.00

1.00

1.00

  Secondary school

1.28

1.02

1.61

0.03

0.86

0.73

1.03

0.10

0.99

0.85

1.15

0.89

0.58

0.42

0.79

 < 0.01

  High school or higher

1.96

1.52

2.52

 < 0.01

1.07

0.89

1.29

0.45

0.94

0.79

1.10

0.43

0.73

0.51

1.04

0.08

 Residence

  Urban (Ref.)

1.00

1.00

1.00

1.00

  Rural

1.15

0.97

1.36

0.11

0.64

0.57

0.72

 < 0.01

1.10

1.00

1.22

0.06

1.10

0.85

1.43

0.47

 Ethnicity

  Han (Ref.)

1.00

1.00

1.00

1.00

  Other

1.34

1.05

1.71

0.02

1.14

0.98

1.32

0.09

0.47

0.41

0.55

 < 0.01

1.40

1.04

1.89

0.03

 Parity

  1 (Ref.)

1.00

1.00

1.00

1.00

  ≥ 2

1.47

1.24

1.73

 < 0.01

1.24

1.12

1.39

 < 0.01

0.93

0.84

1.03

0.15

0.84

0.64

1.10

0.20

 Household income quartiles

  Quartile 1 (Ref.)

1.00

1.00

1.00

1.00

  Quartile 2

1.08

0.88

1.32

0.45

0.97

0.84

1.11

0.63

1.11

0.98

1.26

0.10

0.85

0.64

1.13

0.26

  Quartile 3

1.10

0.90

1.34

0.37

1.15

1.00

1.31

0.05

1.01

0.89

1.14

0.89

0.54

0.39

0.74

 < 0.01

  Quartile 4

1.04

0.81

1.35

0.76

1.36

1.16

1.60

 < 0.01

0.98

0.84

1.14

0.78

0.54

0.35

0.82

0.01

Healthcare-based characteristics

 Frequency of antenatal visit

   < 5 (Ref.)

1.00

1.00

1.00

1.00

  5 ~ 7

1.37

1.08

1.73

0.01

1.03

0.86

1.23

0.74

1.12

0.96

1.31

0.16

0.82

0.60

1.12

0.22

   ≥ 8

1.65

1.32

2.07

 < 0.01

1.09

0.92

1.29

0.32

0.88

0.75

1.02

0.10

0.46

0.33

0.64

 < 0.01

 Mode of delivery

  Vaginal delivery (Ref.)

1.00

1.00

1.00

1.00

  Caesarean section

0.70

0.61

0.81

 < 0.01

0.54

0.49

0.59

 < 0.01

0.89

0.81

0.97

0.01

1.06

0.84

1.33

0.64

 Frequency of postnatal visit

  0(Ref.)

1.00

1.00

1.00

1.00

   ≥ 1

1.31

1.12

1.54

 < 0.01

1.42

1.26

1.59

 < 0.01

0.99

0.90

1.10

0.89

0.90

0.71

1.15

0.42

Infant-based characteristics

 Sex

  Male (Ref.)

1.00

1.00

1.00

1.00

  Female

1.04

0.90

1.20

0.59

1.03

0.94

1.13

0.54

0.99

0.91

1.08

0.86

0.91

0.73

1.14

0.40

 Birth weight (g)

   < 2500 (Ref.)

1.00

1.00

1.00

1.00

  2500 ~ 4000

2.20

1.69

2.87

 < 0.01

1.08

0.85

1.38

0.52

1.43

1.15

1.79

 < 0.01

0.67

0.42

1.07

0.09

   > 4000

2.17

1.53

3.09

 < 0.01

0.87

0.65

1.17

0.36

1.77

1.36

2.31

 < 0.01

0.84

0.48

1.48

0.55