Table 2.
Unadjusted and adjusted ORs1 for the association between developmental vulnerability for each AEDC domain and interpregnancy interval
| AEDC domain and model | Interpregnancy interval (months) | |||||||
| OR (95% CI)† | ||||||||
| <6 | 6–11 | 12–17 | 18–23 | 24–59 | 60–119 | ≥120 | ||
| Physical health and Wellbeing (n=3691)‡ | Unadjusted | 2.01 (1.72 to 2.35)*** | 1.12 (0.98 to 1.27) | 1.02 (0.90 to 1.15) | 1 (referent) | 1.13 (1.01 to 1.26)* | 1.56 (1.36 to 1.78)*** | 1.58 (1.27 to 1.96)*** |
| Adjusted§ | 1.25 (1.06 to 1.48)** | 0.97 (0.84 to 1.10) | 0.98 (0.86 to 1.11) | 1 (referent) | 1.03 (0.92 to 1.16) | 1.35 (1.17 to 1.55)*** | 1.44 (1.14 to 1.82)** | |
| Social Competence (n=2794) | Unadjusted | 1.78 (1.47 to 2.14)*** | 1.23 (1.06 to 1.43)** | 1.11 (0.96 to 1.28) | 1 (referent) | 1.29 (1.13 to 1.46)*** | 1.68 (1.44 to 1.96)*** | 2.10 (1.66 to 2.64)*** |
| Adjusted | 1.19 (0.98 to 1.45) | 1.11 (0.95 to 1.30) | 1.08 (0.93 to 1.25) | 1 (referent) | 1.20 (1.06 to 1.37)** | 1.51 (1.28 to 1.77)*** | 2.01 (1.57 to 2.58)*** | |
| Emotional Maturity (n=2817) | Unadjusted | 1.91 (1.58 to 2.30)*** | 1.36 (1.17 to 1.58)*** | 1.18 (1.02 to 1.37) | 1 (referent) | 1.31 (1.15 to 1.49)*** | 1.71 (1.46 to 1.99)*** | 2.04 (1.61 to 2.59)*** |
| Adjusted | 1.36 (1.12 to 1.66)** | 1.27 (1.09 to 1.48)** | 1.16 (1.00 to 1.35) | 1 (referent) | 1.23 (1.08 to 1.41)** | 1.55 (1.32 to 1.83)*** | 1.90 (1.47 to 2.45)*** | |
| Language and Cognitive Skills (school-based) (n=3381) | Unadjusted | 2.05 (1.73 to 2.42)*** | 1.22 (1.06 to 1.40)** | 1.03 (0.90 to 1.18) | 1 (referent) | 1.35 (1.20 to 1.52)*** | 1.92 (1.67 to 2.21)*** | 1.82 (1.45 to 2.28)*** |
| Adjusted | 1.15 (0.96 to 1.38) | 1.01 (0.87 to 1.17) | 0.98 (0.85 to 1.13) | 1 (referent) | 1.25 (1.10 to 1.42)*** | 1.71 (1.47 to 1.99)*** | 1.87 (1.46 to 2.39)*** | |
| Communication Skills and General Knowledge (n=2856) | Unadjusted | 1.94 (1.63 to 2.32)*** | 1.19 (1.03 to 1.38)* | 1.08 (0.93 to 1.24) | 1 (referent) | 1.24 (1.10 to 1.41)** | 1.55 (1.33 to 1.80)*** | 1.51 (1.18 to 1.93)** |
| Adjusted | 1.20 (1.00 to 1.45) | 1.02 (0.88 to 1.19) | 1.03 (0.89 to 1.19) | 1 (referent) | 1.14 (1.00 to 1.30) | 1.35 (1.15 to 1.58)*** | 1.51 (1.16 to 1.98)** | |
Interpregnancy interval was defined as the time between the birth of the older sibling and the estimated start of the pregnancy (birth date minus gestational age of child, measured in completed weeks of gestation) of the cohort child.
***p<0.001, **p<0.01, *p<0.05.
†All data are presented as ORs (95% CIs) (total population: n=34 574).
‡Number of children classified as vulnerable for each AEDC domain for each cohort.
§Adjusted for maternal smoking status during pregnancy, mode of delivery, preterm birth, small for gestational age, parity, mother’s age at time of child’s birth, sex of child, ethnicity, child speaks a language other than English at home, age of child at time of AEDC completion, number of siblings, mother’s marital status at time of child’s birth, father’s and mother’s occupational status scale at time of child’s birth, Accessibility and Remoteness Index of Australia and Index of Relative Socioeconomic Disadvantage category.
AEDC, Australian Early Development Census.