Table 1. Background characteristics and distress measures according to preterm birth.
| Early preterm | Late preterm | Term | ||
| 22–31 weeks | 32–36 weeks | ≥37 weeks | ||
| n = 272 | n = 1,763 | n = 38,042 | ||
| n (%) | n (%) | n (%) | ||
| Emotional distress at 17 weeks | ||||
| Yes | 21 (7.7) | 125 (7.1) | 2,805 (7.4) | |
| No | 251 (92.3) | 1,638 (92.9) | 35,237 (92.6) | |
| Emotional distress at 30 weeks * | ||||
| Yes | 19 (7.0) | 105 (6.0) | 2,286 (6.0) | |
| No | 94 (34.6) | 1,484 (84.2) | 32,820 (86.3) | |
| Missing | 159 (58.5) | 174 (9.9) | 2,936 (7.7) | |
| Change in emotional distress | ||||
| Increase | 17 (6.3) | 61 (3.5) | 1,254 (3.3) | |
| Decrease or sustained low | 94 (34.6) | 1,484 (84.2) | 32,820 (86.3) | |
| Sustained high | 2 (0.7) | 44 (2.5) | 1,032 (2.7) | |
| Missing | 159 (58.5) | 174 (9.9) | 2,936 (7.7) | |
| Answered questionnaire at 30 weeks * | ||||
| Yes | 125 (46.0) | 1,610 (91.3) | 35,582 (93.5) | |
| No | 147 (54.0) | 153 (8.7) | 2,460 (6.5) | |
| Age (years) | ||||
| <26 | 75 (27.6) | 520 (29.5) | 11,065 (29.1) | |
| 26–30 | 106 (39.0) | 736 (41.7) | 16,956 (44.6) | |
| 31–36 | 74 (27.2) | 429 (24.3) | 8,797 (23.1) | |
| >36 | 17 (6.2) | 78 (4.4) | 1,224 (3.2) | |
| Educational level | ||||
| Primary school | 13 (5.1) | 53 (3.2) | 984 (2.7) | |
| Secondary/Grammar school | 93 (36.2) | 607 (36.2) | 11,887 (32.8) | |
| University/college <4 years | 96 (37.4) | 633 (37.7) | 14,506 (40.0) | |
| University/college ≥4 years | 55 (21.4) | 384 (22.9) | 8,853 (24.4) | |
| Married or cohabiting | 256 (94.1) | 1,663 (94.9) | 35,980 (95.0) | |
| Smoking | 18 (6.6) | 160 (9.1) | 3,001 (7.9) | |
| Pre-pregnancy body mass index (kg/m2) | ||||
| <20 | 33 (12.5) | 238 (13.9) | 5,295 (14.4) | |
| 20–24 | 133 (50.2) | 935 (54.7) | 21,369 (58.0) | |
| 25–29 | 57 (21.5) | 349 (20.4) | 7204 (19.6) | |
| ≥30 | 42 (15.8) | 188 (11.0) | 2,976 (8.1) | |
| Medical risk factors | ||||
| History of spontaneous abortion | 56 (20.6) | 239 (13.6) | 4,951 (13.0) | |
| Late medical risk | 90 (33.1) | 483 (27.4) | 3,633 (9.5) | |
| Birth weight (grams) | ||||
| <1500 | 199 (74.0) | 42 (2.4) | 0 | |
| 1500–3000 | 70 (26.0) | 1,449 (82.2) | 4,172 (11.0) | |
| >3000 | 0 | 272 (15.4) | 33,848 (89.0) | |
| New-born gender | ||||
| Boy | 139 (51.1) | 944 (53.5) | 19,418 (51.0) | |
| Girl | 133 (48.9) | 819 (46.5) | 18,624 (49.0) | |
| Any covariate missing | 32 (11.8) | 216 (12.3) | 4,656 (12.2) | |
| Start of birth | ||||
| Spontaneous | 157 (42.3) | 1,299 (73.7) | 32,712 (86.0) | |
| Provider-initiated | 115 (42.3) | 464 (26.3) | 5,330 (14.0) | |
*mean gestational age for filling out questionnaire 2 was 30 weeks, SD 2 weeks. However, some women filled out the form before 30 weeks' gestation while some gave birth after week 30 (in week 31). As a result, approximately 40% of those giving birth early preterm filled out questionnaire 2 and the SCL-5 a second time, even though they delivered early preterm.