Table 1.
Perinatal mortality for singleton births in Norway 1967–1976 (n = 531 098) and 1977–1986 (n = 416 735) according to LMP-based gestational age and size at birth (small-for-gestational-age [SGA] and non-SGA)
| |
Non-SGA |
SGA |
|||||
|---|---|---|---|---|---|---|---|
| Gestational age in weeks | Perinatal deaths n (per 1000) | Adjusted OR α | 95% CI | Perinatal deaths n (per 1000) | SGA% of deaths per week | Adjusted OR α | 95% CI |
|
1967–1976 | |||||||
|
37 |
192 (11.4) |
4.1 |
3.5–4.9 |
213 (89.0) |
52.6 |
35.1 |
29.5–41.7 |
|
38 |
228 (5.6) |
2.0 |
1.7–2.4 |
226 (40.7) |
49.8 |
15.3 |
13.0–18.1 |
|
39 |
293 (3.1) |
1.1 |
0.96–1.3 |
236 (18.3) |
44.6 |
6.9 |
5.8–8.1 |
|
40 |
379 (2.7) |
1.0 |
Reference |
222 (11.3) |
36.9 |
4.3 |
3.6–5.1 |
|
41 |
327 (3.0) |
1.1 |
0.98–1.3 |
187 (12.4) |
36.4 |
4.7 |
4.0–5.6 |
|
≥42 |
316 (4.8) |
1.8 |
1.6–2.1 |
150 (15.1) |
32.2 |
5.8 |
4.8–7.0 |
|
1977–1986 | |||||||
|
37 |
94 (7.3) |
5.4 |
4.2–7.0 |
103 (62.0) |
52.3 |
49.0 |
37.9–63.4 |
|
38 |
110 (3.5) |
2.6 |
2.0–3.3 |
78 (19.0) |
41.5 |
14.4 |
11.0–19.0 |
|
39 |
155 (2.1) |
1.5 |
1.2–1.9 |
87 (9.3) |
36.0 |
7.1 |
5.4–9.2 |
|
40 |
147 (1.3) |
1.0 |
Reference |
100 (7.4) |
40.5 |
5.6 |
4.4–7.3 |
|
41 |
150 (1.7) |
1.3 |
1.01–1.6 |
92 (8.8) |
38.0 |
6.7 |
5.2–8.8 |
| ≥42 | 124 (2.4) | 1.8 | 1.4–2.3 | 57 (8.8) | 31.5 | 6.7 | 4.9–9.1 |
Pregnancies with preeclampsia, pregestational and gestational diabetes and infants with congenital anomalies were excluded.
αAdjustments by logistic regression where the following confounders were included: maternal age (<20, 20–24, 25–29, 30–34 and 35+), parity (para 0, para 1+) and fetal sex.