Baseline characteristics of immigrant and nonimmigrant women who gave birth in Ontario during the study period
| Characteristic | No. (%) of women* | |
|---|---|---|
| Immigrants n = 327 279 | Nonimmigrants n = 942 502 | |
| Demographic | ||
| Age, mean ± SD, yr | 30.5 ± 5.2 | 29.7 ± 5.6 |
| Primiparous | 141 131 (43.1) | 435 940 (46.3) |
| Lowest neighbourhood income quintile | 112 624 (34.4) | 175 588 (18.6) |
| Maternal morbidity within 2 yr before the index birth | ||
| Diabetes mellitus before or in pregnancy | 6445 (2.0) | 16 057 (1.7) |
| Hypertension before or in pregnancy | 6276 (1.9) | 26 657 (2.8) |
| Health care resource utilization bands 4 and 5 (highest) | 233 840 (71.4) | 638 345 (67.7) |
| Psychiatric morbidity within 2 yr before the index birth | ||
| Mood disorder | 7372 (2.3) | 46 849 (5.0) |
| Psychotic disorder | 680 (0.2) | 2929 (0.3) |
| Substance or alcohol use disorder | 1613 (0.5) | 24 966 (2.6) |
| Primary care physician visit for a psychiatric disorder | 75 978 (23.2) | 271 515 (28.8) |
| Psychiatrist visit | 5518 (1.7) | 34 413 (3.7) |
| Psychiatric hospital admission | 532 (0.2) | 4358 (0.5) |
| Deliberate self-harm | 2588 (0.8) | 20 396 (2.2) |
| Obstetrical and perinatal indicators at the index birth | ||
| Preterm birth < 37 wk gestation | 21 594 (6.6) | 68 637 (7.3) |
| Birth weight, mean ± SD, g | 3282 ± 557 | 3410 ± 584 |
| Cesarean delivery | 92 094 (28.1) | 258 841 (27.5) |
| Neonatal morbidity | ||
| Respiratory distress syndrome | 3724 (1.1) | 14 216 (1.5) |
| Seizure | 949 (0.3) | 3583 (0.4) |
| Sepsis | 4144 (1.3) | 14 094 (1.5) |
| Intraventricular hemorrhage | 1745 (0.5) | 5490 (0.6) |
| Persistent fetal circulation | 893 (0.3) | 3172 (0.3) |
| Congenital/neonatal infection | 1219 (0.4) | 1219 (0.4) |
| Neonatal intensive care unit admission | 45 976 (14.0) | 121 434 (12.9) |
| Infant mortality < 365 d of the index birth, no. (rate) | 1227 (3.8 per 1000) | 3276 (3.5 per 1000) |
Note: SD = standard deviation.
↵* Unless specified otherwise.