Variables

N

% cesarean

Prevalence ratio (crude)

CI¹

Prevalence ratio (adjusted)^**

CI²

Type of hospital

Public

149,800

32.1

1

1

-

Mixed

38,583

44.4

1.38

1.35 - 1.41

1.31

1.28 - 1.33^*

Private

116,784

82.7

2.58

2.54 - 2.62

2.20

2.17 - 2.23^*

Mother’s age (years)

≤19

43,293

32.2

0.40

0.39 - 0.41

0.74

0.72 - 0.76

20 to 34

219,317

54.4

1

1

-

≥35

42,557

68.3

1.81

1.77 - 1.85

1.17

1.15 - 1.18

Maternal education (years)

<4

62,536

38.1

1

1

-

4 to 11

180,394

50.4

1.23

1.21 - 1.25

1.02

1.00 - 1.04^*

≥12

60,574

77.0

1.99

1.59 - 1.61

1.05

1.03 - 1.07^*

Parity

Nulliparous

133,820

57.4

1.28

1.26 - 1.30

1.09

1.07 - 1.11

Multiparous

142,441

51.3

1

1

-

Grand multiparous

14,612

33.6

0.48

0.46 - 0.50

0.83

0.80 - 0.86

Newborn skin color

White

206,764

58.3

1.89

1.86 - 1.92

1.05

1.04 - 1.06

Non-white

98,403

42.4

1

1

-

Pregnancy

Single

297,717

52.3

1

1

-

Multiple

7450

87.3

1.67

1.65 - 1.68

1.48

1.44 - 1.52

Gestational age (weeks)

-

<37

27,119

58.4

1.26

1.23 - 1.30

1.03

1.01 - 1.05

≥37

278,404

52.7

1

1

-

Number of prenatal visits

≤3

16,367

27.5

1

1

-

4 to 6

63,646

39.1

1.30

1.26 - 1.34

1.23

1.18 - 1.28^*

≥7

223,831

59.1

1.72

1.67 - 1.77

1.37

1.33 - 1.41^*

Volume of hospital births (births/year)

≤1000

28,750

66.6

1.29

1.26 - 1.33

1.12

1.10 - 1.13

>1000

276,417

51.8

1

1

-

Hospital location

In the city of residence

247,597

50.3

1

1

-

Outside the city of residence

57,570

65.6

1.30

1.27 - 1.33

1.04

1.02 - 1.06

Total

305,167

53.2