Background
Methods
Study design
Setting
Study population
Stillbirth
Migration related factors
Other variables
Statistics
Results
Primiparous women | Multiparous women | |||
---|---|---|---|---|
Migrant | Non-migrant | Migrant | Non-migrant | |
(n = 80,119) | (n = 468,983) | (n = 115,606) | (n = 667,654) | |
n (%)
|
n (%)
|
n (%)
|
n (%)
| |
Age (years) | ||||
< 25 | 23,983 (29.9) | 163,323 (34.8) | 12,629 (10.9) | 63,940 (9.6) |
25–29 | 29,379 (36.7) | 180,607 (38.5) | 34,481 (29.8) | 212,756 (31.9) |
30–34 | 19,392 (24.2) | 93,888 (20.0) | 40,957 (35.4) | 254,405 (38.1) |
35–39 | 6338 (7.9) | 26,923 (5.7) | 22,501 (19.5) | 116,858 (17.5) |
≥40 | 1027 (1.3) | 4242 (0.9) | 5038 (4.4) | 19,695 (2.9) |
Single status b | 6652 (8.3) | 58,059 (12.4) | 8864 (7.7) | 34,807 (5.2) |
Consanguinity, second cousin or closer | 2082 (2.6) | 594 (0.1) | 4467 (3.9) | 1167 (0.2) |
Mother’s education | ||||
No education | 856 (1.1) | 4 (0.0) | 3541 (3.1) | 41 (0.0) |
Primary education | 15,538 (19.4) | 96,802 (20.6) | 30,960 (26.8) | 147,867 (22.1) |
Secondary school | 15,897 (19.8) | 180,494 (38.5) | 23,811 (20.6) | 255,916 (38.3) |
University/college | 26,002 (32.5) | 190,883 (40.7) | 29,978 (25.9) | 262,404 (39.3) |
Missing | 21,826 (27.2) | 800 (0.2) | 27,316 (23.6) | 1426 (0.2) |
Mother’s incomec | ||||
≤25 percentile | 18,250 (22.8) | 98,494 (21.0) | 26,044 (22.5) | 146,471 (21.9) |
25–50 percentile | 12,391 (15.5) | 98,342 (21.0) | 16,943 (14.7) | 163,221 (24.4) |
50–75 percentile | 8793 (11.0) | 121,703 (26.0) | 10,600 (9.2) | 148,630 (22.3) |
≥75 percentile | 9898 (12.4) | 122,450 (26.1) | 11,149 (9.6) | 142,284 (21.3) |
Missing | 30,787 (38.4) | 27,994 (6.0) | 50,870 (44.0) | 67,048 (10.0) |
Chronic hypertension | 245 (0.3) | 2043 (0.4) | 518 (0.4) | 3506 (0.5) |
Pre-eclampsia/eclampsia | 2971 (3.7) | 25,391 (5.4) | 2252 (1.9) | 15,988 (2.4) |
Pre-pregnancy diabetes d | ||||
Type 1 | 152 (0.2) | 1616 (0.3) | 314 (0.3) | 2057 (0.3) |
Type 2 | 157 (0.2) | 402 (0.1) | 476 (0.4) | 746 (0.1) |
Maternal overweight (BMI ≥ 25) e | 3501 (10.4) | 17,673 (16.1) | 7454 (16.5) | 26,520 (17.7) |
Not overweight | 12,622 (37.5) | 33,785 (30.8) | 12,887 (28.5) | 42,331 (28.2) |
Missing | 17,548 (52.1) | 58,371 (53.1) | 24,952 (55.1) | 81,359 (54.2) |
Smoking before pregnancy e | 3133 (5.0) | 21,990 (7.9) | 3014 (3.4) | 22,603 (5.7) |
Non-smoker | 21,343 (33.7) | 67,540 (24.4) | 29,655 (33.3) | 104,803 (26.6) |
Missing | 38,807 (61.3) | 187,681 (67.7) | 56,414 (63.3) | 267,054 (67.7) |
Former stillbirths | 2639 (2.3) | 9336 (1.4) | ||
Parity | ||||
0 | 80,119 (100.0) | 468,983 (100.0) | ||
1 | 64,191 (55.5) | 411,085 (61.6) | ||
2 | 29,859 (25.8) | 189,681 (28.4) | ||
3 | 12,127 (10.5) | 48,959 (7.3) | ||
4 | 5043 (4.4) | 11,999 (1.8) | ||
≥5 | 4386 (3.8) | 5930 (0.9) | ||
Gestational age (weeks) | ||||
Very preterm (22–27 weeks) | 403 (0.5) | 2247 (0.5) | 591 (0.5) | 2576 (0.4) |
Moderately preterm (28–36 weeks) | 4951 (6.2) | 30,779 (6.6) | 6481 (5.6) | 31,701 (4.7) |
Term (37–41 weeks) | 66,354 (82.8) | 367,439 (78.3) | 98,033 (84.8) | 552,939 (82.8) |
Post term (≥ 42 weeks) | 6454 (8.1) | 49,734 (10.6) | 6969 (6.0) | 52,688 (7.9) |
Missing | 1957 (2.4) | 18,784 (4.0) | 3532 (3.1) | 27,750 (4.2) |
Primiparous | Multiparous | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
n | Stillbirths | (%) | Crude OR (95% CI) | Adjusteda OR (95% CI) | n | Stillbirths | (%) | Crude OR (95% CI) | Adjustedb OR (95% CI) | |
Paternal origin | ||||||||||
Foreign-born (ref) | 47,109 | 233 | (0.5) | 1.00 | 1.00 | 73,487 | 313 | (0.4) | 1.00 | 1.00 |
Norwegian-born | 30,175 | 119 | (0.4) | 0.80 (0.63 to 1.00) | 0.73 (0.58 to 0.93) | 31,643 | 106 | (0.3) | 0.79 (0.63 to 0.98) | 0.83 (0.65 to 1.05) |
Missing c | 4029 | 90 | (2.2) | 4.60 (3.59 to 5.89) | 6.29 (4.64 to 8.51) | 12,077 | 247 | (2.0) | 4.88 (4.12 to 5.79) | 5.72 (4.70 to 6.96) |
Reason for immigration d | ||||||||||
Nordic migrants (ref) | 56 | (0.6) | 1.00 | 1.00 | 9145 | 37 | (0.4) | 1.00 | 1.00 | |
Work/Education | 13,410 | 46 | (0.3) | 0.54 (0.36 to 0.80) | 0.58 (0.39 to 0.88) | 9057 | 38 | (0.4) | 1.04 (0.66 to 1.64) | 1.21 (0.76 to 1.92) |
Family reunion or establishment | 38,083 | 196 | (0.5) | 0.81 (0.60 to 1.09) | 0.76 (0.55 to 1.06) | 53,209 | 281 | (0.5) | 1.31 (0.92 to 1.86) | 1.22 (0.85 to 1.74) |
Refuge | 9467 | 62 | (0.7) | 1.03 (0.71 to 1.48) | 0.92 (0.62 to 1.37) | 20,623 | 138 | (0.7) | 1.66 (1.14 to 2.41) | 1.41 (0.95 to 2.11) |
Length of residence | ||||||||||
< 2 years (ref) | 30,801 | 148 | (0.5) | 1.00 | 1.00 | 18,029 | 99 | (0.5) | 1.00 | 1.00 |
2–5 years | 28,095 | 158 | (0.6) | 1.17 (0.93 to 1.47) | 1.20 (0.94 to 1.53) | 42,549 | 221 | (0.5) | 0.95 (0.75 to 1.20) | 0.97 (0.76 to 1.24) |
6–9 years | 10,299 | 64 | (0.6) | 1.30 (0.96 to 1.75) | 1.28 (0.93 to 1.77) | 27,294 | 160 | (0.6) | 1.07 (0.83 to 1.37) | 1.04 (0.80 to 1.36) |
≥ 10 years | 12,118 | 72 | (0.6) | 1.24 (0.93 to 1.65) | 1.27 (0.93 to 1.74) | 29,335 | 186 | (0.6) | 1.16 (0.90 to 1.48) | 1.06 (0.81 to 1.39) |
Birthplace of firstborn child | ||||||||||
Norway (ref) | 52,834 | 231 | (0.4) | 1.00 | 1.00 | |||||
Other than Norway | 40,483 | 267 | (0.7) | 1.51 (1.26 to 1.81) | 1.28 (1.06 to 1.55) |