Table 1 Characteristics of mothers with and without depression (N = 107587)
| Â | Maternal perinatal depression* | |||
|---|---|---|---|---|
|  | No (n = 97,815) N (%) | Yes (n = 9,772) N (%) | χ2(df†) | P |
Maternal age at birth of child (years) | ||||
   Mean (Standard deviation) | 29.2 (5.6) | 28.6 (5.9) | tα = 9.5 (107585) | < 0.001 |
Maternal body mass index (kg/m2) | ||||
   Normal (18.5-24.9) | 37971 (38.8) | 4069 (41.6) | 575.9 (4) | < 0.001 |
   Underweight (<18.5) | 2660 (2.7) | 395 (4.0) |  |  |
   Overweight (25-29.9) | 12093 (12.4) | 1502 (15.4) |  |  |
   Obese (>30) | 5653 (5.8) | 910 (9.3) |  |  |
   Missing | 39438 (40.3) | 2896 (29.6) |  |  |
Maternal smoking | ||||
   Non-smoker | 47266 (48.3) | 3952 (40.4) | 1300 (3) | < 0.001 |
   Ex-smoker | 4698 (4.8) | 567 (5.8) |  |  |
   Current smoker | 19985 (20.4) | 3463 (35.4) |  |  |
   Missing | 25866 (26.4) | 1790 (18.3) |  |  |
Household socioeconomic status | ||||
   1 (Least deprivation) | 16028 (16.4) | 1112 (11.4) | 419.1 (5) | < 0.001 |
   2 | 11714 (12.0) | 972 (10.0) |  |  |
   3 | 11170 (11.4) | 1106 (11.3) |  |  |
   4 | 9298 (9.5) | 1214 (12.4) |  |  |
   5 (Most deprivation) | 7063 (7.2) | 1078 (11.0) |  |  |
   Missing | 42542 (43.5) | 4290 (43.9) |  |  |
Caesarean section delivery | 13604 (13.9) | 1616 (16.5) | 50.6 (1) | < 0.001 |
Sex of the child | ||||
   Male | 50192 (51.3) | 4922 (50.4) | 3.2 (1) | 0.075 |