Table 8 Uni- and multivariable regression analysis of risk factors for perinatally-associated mortality in all births^a

Variables

Category

Mortality (%)

OR

95% CI

P values

 Hospital level

III

1.1

II

0.6

0.503

0.403–0.629

< 0.001

I

0.2

0.187

0.131–0.266

< 0.001

 Sex

Male

0.7

Female

0.5

0.777

0.628–0.960

0.019

 Multi-births

No

0.5

Yes

4.8

9.753

7.347–12.946

< 0.001

 Congenital anomalies

No

0.5

Yes

13.6

29.303

20.927–41.030

< 0.001

 Cesarean delivery

No

0.8

Yes

0.4

0.517

0.417–0.640

< 0.001

 High risk pregnancy

No

0.2

Yes

0.8

4.382

2.939–6.535

< 0.001

 Pregnancy complications

No

0.6

Yes

0.8

1.383

1.058–1.809

0.018

 Low birthweight (< 2500 g)

No

0.3

Yes

10.6

37.807

30.543–46.799

< 0.001

 Preterm birth (< 37 weeks)

No

0.3

Yes

8.5

34.507

27.868–42.728

< 0.001

 Maternal education (< 10 years)

No

0.7

Yes

0.5

0.720

0.585–0.887

0.002

 Maternal age (≥35 years old)

No

0.6

Yes

0.8

1.353

0.969–1.888

0.073

 AF contamination

No

0.5

Yes

1.3

2.741

2.185–3.439

< 0.001

 Abnormal amniotic fluid volume

No

0.6

Yes

0.8

1.516

1.174–1.958

0.001

 First delivery

No

0.5

Yes

0.8

1.716

1.392–2.114

<0.001

 1-min Apgar (≤7)

No

0.2

Yes

16.6

118.149

92.994–150.110

< 0.001

 5-min Apgar (≤7)

No

0.2

Yes

43.7

391.298

305.437–501.294

< 0.001

Variables

Reference^b

OR

P values

Lower

Upper

 Hospital level

I

0.729

0.456

1.166

0.187

II

0.925

0.670

1.276

0.634

 Sex

Male

0.815

0.619

1.074

0.146

 Multi-births

No

2.331

1.451

3.744

< 0.001

 Congenital anomalies

No

14.699

7.850

27.527

< 0.001

 High risk pregnancy

No

1.510

0.941

2.422

0.088

 Cesarean delivery

No

0.635

0.480

0.840

0.001

 LBW (< 2500 g)

No

 Preterm birth (< 37 weeks)

No

 Maternal education (< 10 years)

No

 Maternal age (≥ 35 years old)

No

 AF contamination

No

 Abnormal amniotic fluid volume

No

 First delivery

No

 1-min Apgar (≤7)

No

 5-min Apgar (≤7)

No