Participant characteristics
| Variable | Overall | White European | South Asian | East/South-East Asian | Aboriginal | Other ethnicity | African | P value* |
| n | 3997 | 2367 | 884 | 335 | 190 | 141 | 60 | |
| Maternal | ||||||||
| Age at enrolment (years) | 31.6 (4.7) | 32.1 (4.6) | 30.2 (4.0) | 33.1 (4.2) | 28.0 (6.0) | 32.2 (5.1) | 31.2 (5.4) | <0.001 |
| Height (cm) | 164.4 (6.9) | 166.0 (6.5) | 162.2 (6.4) | 160.2 (6.6) | 165.3 (6.9) | 161.5 (6.3) | 163.7 (7.7) | <0.001 |
| Prepregnancy weight (kg) | 66.8 (13.9) | 69.1 (14.1) | 62.4 (11.9) | 58.7 (9.2) | 75.4 (16.9) | 64.3 (10.6) | 69.7 (14.2) | <0.001 |
| Prepregnancy body mass index (kg/m2) | 24.7 (4.8) | 25.1 (5.0) | 23.7 (4.4) | 23.0 (3.3) | 27.6 (6.2) | 24.8 (4) | 26 (4.8) | <0.001 |
| Final pregnancy weight (kg) | 81.4 (15.7) | 84.2 (16.2) | 76.5 (12.7) | 72.4 (12.5) | 91.3 (22.7) | 80.1 (14.1) | 83.1 (14.8) | <0.001 |
| Primiparous (%) | 49.8 | 51.3 | 41.8 | 59.7 | 40.8 | 58.9 | 45.0 | <0.001 |
| Gestational diabetes (%) | 11.3 | 7.4 | 24.2 | 10.8 | 4.2 | 9.2 | 5.0 | <0.001 |
| Years lived in Canada | 23.4 (12.2) | 29.2 (8.3) | 8.4 (7.8) | 20.4 (12.5) | 28.5 (5.8) | 17.2 (12.4) | 19.4 (12.6) | <0.001 |
| Postsecondary education (%) | 85.1 | 86.8 | 84.7 | 95.2 | 52.9 | 82.6 | 85.0 | <0.001 |
| Smoking during pregnancy (%) | ||||||||
| Never smoked | 77.1 | 70.4 | 99.6 | 87.7 | 40.6 | 71.6 | 88.3 | <0.001 |
| Quit before pregnancy | 16.2 | 21.8 | 0.2 | 9.9 | 25.7 | 21.3 | 5.0 | <0.001 |
| Quit during pregnancy | 3.6 | 4.3 | 0.2 | 1.8 | 15.5 | 5.7 | 1.7 | <0.001 |
| Currently smoking | 3.1 | 3.5 | 0.0 | 0.6 | 18.2 | 1.4 | 5.0 | <0.001 |
| Household income (%) | ||||||||
| Total income ≥$60K | 77.2 | 88.9 | 43.5 | 87.2 | 48.1 | 80.3 | 68.3 | <0.001 |
| Multivitamin use (%) | 85.8 | 89.3 | 71.8 | 95.9 | 91.4 | 87.4 | 83.4 | <0.001 |
| Vegetarianism (%) | 12.3 | 3.5 | 37.1 | 0.0 | 0.0 | 0.0 | 0.0 | <0.001 |
| Newborn | ||||||||
| Sex (% male) | 51.8 | 52.3 | 49.1 | 52.2 | 46.8 | 58.2 | 53.2 | 0.42 |
| Gestational age (weeks) | 39.6 (1.1) | 39.7 (1.1)a | 39.4 (1.1)b | 39.4 (1.1)bc | 39.6 (1.1)ac | 39.8 (1) | 39.5 (1.1) | <0.001 |
| Birth weight (g) | 3432 (466) | 3493 (457)a | 3265 (438)b | 3330 (448)c | 3567 (469)d | 3456 (481) | 3347 (468) | <0.001 |
| Birth length (cm) | 51.3 (2.5) | 51.4 (2.5)ab | 51.3 (2.5)ab | 51.0 (2.4)b | 51.6 (3.2)a | 51.2 (2.3) | 51.4 (2.4) | 0.18 |
| LGA (n) | 370 (9.8%) | 224 (9.9%) | 87 (9.9%) | 30 (9.2%) | 18 (9.6%) | 12 (9.0%) | 10 (17%) | 0.60 |
| SGA (n) | 348 (9.2%) | 219 (9.6%) | 83 (9.4%) | 29 (8.9%) | 14 (7.5%) | 10 (7.4%) | 1 (1.7%) | 0.36 |
*Continuous measures (mean and SD) were compared using analysis of variance, and categorical variables were compared using χ2. Non-matching superscript letters indicate significant difference (P<0.05) between ethnic groups. Data on parity, prepregnancy weight, smoking history, ethnicity, postgraduate education, marital status, employment status and total household income were self-reported. Maternal age, height and gestational age of offspring at birth were obtained from participant medical records. Last measured maternal pregnancy weight was obtained from medical records at time of birth (ABC, FAMILY and START) or using a combination of medical records or maternal recollection (CHILD). Gestational diabetes was determined either through (1) self-reported by the mother or recorded from the medical chart (CHILD), or (2) diagnosed using an oral glucose tolerance test, self-reported by the mother or recorded from the medical chart (ABC, FAMILY and START).
ABC, Aboriginal Birth Cohort; CHILD, Canadian Healthy Infant Longitudinal Development study; FAMILY, Family Atherosclerosis Monitoring In earLY life; LGA, ethnic-specific large-for-gestational age (birth weight ≥90th percentile for gestational age and sex); SGA, ethnic-specific small-for-gestational age (birth weight <10th percentile for gestational age and sex); START, SouTh Asian birth cohoRT.