Table 2: Cohort demographics and perinatal factors.
|
s.31 infants,
N = 1,332 |
Comparison group,
N = 204,417 |
p | |
| Gender | |||
| Female | 626 (47.0%) | 99,965 (48.9%) | |
| Male | 706 (53.0%) | 104,452 (51.1%) | |
| Deprivation Quintile | ∗ ∗ ∗ | ||
| 1 Least deprived | 129 (9.7%) | 33,790 (16.5%) | |
| 2 | 175 (13.1%) | 31,799 (15.6%) | |
| 3 | 239 (17.9%) | 38,713 (18.9%) | |
| 4 | 299 (22.4%) | 43,691 (21.4%) | |
| 5 Most deprived | 490 (36.8%) | 56,424 (27.6%) | |
| Birth weight category | ∗ ∗ ∗ | ||
| Normal (2.5–4.0kg) | 1,028 (77.2%) | 165,535 (81.0%) | |
| Very or extremely low (<1.5kg) | 29 (2.2%) | 1,850 (0.9%) | |
| Low (1.5–2.5kg) | 198 (14.9%) | 12,141 (5.9%) | |
| High (4–4.5kg) | 59 (4.4%) | 19,479 (9.5%) | |
| Very or extremely high (>4.5kg) | 10 (0.8%) | 3,370 (1.6%) | |
| Missing | 8 (0.6%) | 2,042 (1.0%) | |
| Maternal age at birth* | 25.6 (6.3) | 29.3 (5.7) | ∗ ∗ ∗ |
| Gestational age category | ∗ ∗ ∗ | ||
| Term (37–41 weeks) | 1,085 (81.5%) | 178,610 (87.4%) | |
| Very or extremely pre-term (<31 weeks) | 29 (2.2%) | 2080 (1.0%) | |
| Pre-term (32–36 weeks) | 170 (12.8%) | 12,629 (6.2%) | |
| Late term (42–44 weeks) | 38 (2.9%) | 8,449 (4.1%) | |
| Missing | 10 (0.8%) | 2,649 (1.3%) | |
| Total birth number | |||
| 1 | 1,281 (96.2%) | 19,8624 (97.2%) | |
| 2+ | 51 (3.8%) | 5631 (2.8%) | |
| Previous live births (parity) | ∗ ∗ ∗ | ||
| 0 | 453 (34%) | 78,276 (34.7%) | |
| 1 | 276 (20.7%) | 59,733 (26.5%) | |
| 2 | 198 (14.9%) | 23,204 (10.3%) | |
| 3+ | 239 (17.9%) | 34,620 (15.4%) | |
| Missing | 166 (12.5%) | 29,688 (13.2%) | |
| Apgar score | ∗ ∗ ∗ | ||
| 10 | 746 (63.8%) | 121,920 (65.9%) | |
| 9 | 335. (28.6%) | 54,093 (29.2%) | |
| <9 | 89 (7.7%) | 9063 (4.9%) | |
| Missing | 162 (12%) | 19,341 (9%) | |
| Known smoker | 309 (23%) | 16,774 (8.2%) | ∗ ∗ ∗ |
| Missing | 845 (62%) | 131,292 (63%) | |
| Maternal substance use | ∗ ∗ ∗ | ||
| Alcohol | 296 (22%) | 6,692 (3%) | |
| Substance use | 189 (14%) | 3,010 (1%) | |
| Any maternal mental health record | 1,005 (75%) | 62,872 (31%) | ∗ ∗ ∗ |
Note: shows n and (%) unless otherwise indicated; Maternal substance use and mental health is based on any maternal event recorded before the child’s birth; Variables: *Mean (standard deviation, SD); p-value: *** = < 0.001, ** < 0.01.