Skip to main content

Table 2 Constitution of GA-specific mortality rates or corrected by the total births of whole region

From: A birth population-based survey of preterm morbidity and mortality by gestational age

GA, weeks

25–27

28–31

32–33

34–36

25–36

Preterm births, n

85

314

428

1824

2651

Prevalence, ‰1

1.4

5.3

7.2

30.8

44.7

Perinatal mortality, n

49

83

32

60

224

R1, %

57.6

26.4

7.5

3.3

8.4

R2, ‰

0.8

1.4

0.5

1.0

3.8

Fetal deaths / stillbirths, n

31

49

20

37

137

R1, %

36.5

15.6

4.7

2.0

5.2

R2, ‰

0.5

0.8

0.3

0.6

2.3

Deaths at DR, n

12

11

2

2

27

R1, %

14.1

3.5

0.5

0.1

1.0

R2, ‰

0.2

0.2

0.0

0.0

0.5

Neonatal mortality, n

24

42

15

26

107

R1, %2

44.4

15.8

3.7

1.5

4.3

R2, ‰3

0.4

0.7

0.3

0.4

1.8

All deaths, n

61

93

35

63

252

R1, %

71.8

29.6

8.2

3.5

9.5

R2, ‰

1.0

1.6

0.6

1.1

4.3

  1. Abbreviations: GA, gestational age; DR, delivery room. Values are number (n) or rate. GA-specific mortality rate (R1, %) = (number of deaths of each GA stratum / number of births of the same GA stratum) × 100; GA-specific mortality rate corrected by the number of total births (including term and post term births) of whole region (R2, ‰) = GA-specific mortality rate × prevalence of each GA in the total births = (number of deaths of each GA stratum / the number of total births [59,245]) × 1000. For definition of all-death see Table 1 legends, note 6
  2. 1. Prevalences of each GA in the total births (‰) = (number of births of each GA stratum / the number of total births) × 1000
  3. 2. R1, calculated by number of neonatal deaths of each GA stratum divided by number of livebirths in the same GA stratum
  4. 3. R2, calculated by number of neonatal deaths of each GA stratum divided by the number of livebirths (including term and post term births) of whole region (59,056)