Table 1 Demographic and clinical characteristics of the study population.

Female sex

46.2

48.6

0.96 (0.93–0.99), 0.006

 Caucasians

42.5

46.5

Reference

 African Americans

20.6

13.3

1.36 (1.31–1.42), <0.0001

 Hispanic/Latinos

15.8

18.1

0.98 (0.94–1.02), <0.0001

 Asian/Pacific Islanders

4.38

5.44

0.97 (0.89–1.04), 0.002

 Native Americans

0.81

0.65

1.18 (1.00–1.39), 0.18

Singleton

93.5

96.7

0.96 (0.90–1.02), 0.21

Cesarean delivery

72.5

32.9

5.24 (5.06–5.43), <0.0001

Small for gestational age

3.35

1.62

1.67 (1.54–1.81), <0.0001

Maternal hypertension

4.74

0.55

2.32 (2.16–2.49), <0.0001

Maternal diabetes

5.06

3.05

1.00 (0.94–1.07), 0.91

Maternal chorioamnionitis

2.49

1.01

1.13 (1.03–1.25), 0.01

Placenta previa

1.15

0.07

3.79 (3.29–4.37), <0.0001

Cord prolapse

0.45

0.05

2.18 (1.74–2.74), <0.0001

Nuchal cord

3.83

1.33

2.63, (2.44–2.84), <0.0001

Breech presentation

3.64

0.67

2.19 (2.03–2.38), <0.0001

Malpresentation

0.79

0.55

1.03 (0.87–1.22), 0.71

Congenital heart diseases

13.6

2.44

1.21 (1.16–1.27), <0.0001

Diaphragmatic hernia

0.08

0.04

1.78 (1.07–2.96), 0.026

Abdominal wall defects

0.10

0.08

1.29 (0.83–1.99), 0.26

Chromosomal disorders

0.16

0.21

0.29 (0.20–0.42), <0.0001

Respiratory distress syndrome

44.9

4.99

6.41 (6.17–6.66), <0.0001

Pneumothorax

3.38

0.47

1.52 (1.39–1.65), <0.0001

Pulmonary hemorrhage

0.16

0.01

1.75 (1.21–2.51), <0.001

Pulmonary hypertension

3.07

0.33

1.48 (1.35–1.62), <0.0001

Anemia of prematurity

21.9

1.38

1.79 (1.71–1.89), <0.0001

Early or late sepsis

13.0

1.58

1.59 (1.52–1.68), <0.0001