Participant characteristics for nested case–control metabolite analysis, IADPSG criteria for GDM diagnosis
| Overall, START and FAMILY (n=590) | START, South Asian mothers (n=299) | FAMILY, white European mothers (n=291) | ||||
| GDM (n=133, 22.5%) | No GDM (n=457) | GDM (n=81, 27.1%) | No GDM (n=218) | GDM (n=52, 17.9%) | No GDM (n=239) | |
| Age, mean (SD) | 32.2 (4.9) | 30.9 (4.4) | 31.1 (4.2) | 29.6 (3.5) | 33.9 (5.4) | 32.0 (4.8) |
| Gestational age at recruitment, mean (SD) | 27.6 (3.1) | 28.2 (3.3) | 26.4 (2.1) | 26.7 (1.6) | 29.4 (3.6) | 29.6 (3.8) |
| Pre-pregnancy BMI, mean (SD) | 27.3 (6.6) | 24.7 (5.1) | 25.3 (5.2) | 24.5 (3.8) | 30.5 (7.3) | 25.8 (5.8) |
| Mean height, cm (SD) | 162.1 (6.2) | 164.0 (6.7) | 161.2 (6.0) | 162.3 (6.5) | 163.6 (6.4) | 165.6 (6.5) |
| Gravida, mean (SD) | 2.6 (1.6) | 2.3 (1.3) | 2.5 (1.3) | 2.3 (1.1) | 2.7 (1.9) | 2.3 (1.5) |
| Family history of diabetes, n (%) | 64 (48.1) | 134 (29.3) | 47 (58.0) | 90 (41.3) | 17 (32.7) | 44 (18.4) |
| Unknown | 7 (5.3) | 20 (4.4) | 2 (2.5%) | 2 (0.9) | 5 (9.6) | 18 (7.5) |
| Parity, n (%) | ||||||
| Primiparous | 49 (36.8) | 196 (42.9) | 27 (33.3) | 79 (36.2) | 22 (42.3) | 117 (49.0) |
| Multiparous | 84 (63.2) | 260 (56.9) | 54 (66.7) | 139 (63.8) | 30 (57.7) | 121 (50.6) |
| Unknown | 0 (0) | 1 (0.2) | 0 (0) | 0 (0) | 0 (0) | 1 (0.4) |
| Glucose, mean (SD), mmol/L | ||||||
| Fasting, plasma | 5.0 (0.8) | 4.3 (0.3) | 5.0 (0.8) | 4.3 (0.3) | 5.1 (0.7) | 4.3 (0.3) |
| 1-hour GTT | 10.0 (1.9) | 7.2 (1.4) | 10.2 (2.0) | 7.3 (1.4) | 9.7 (1.8) | 7.1 (1.4) |
| 2-hour GTT | 8.0 (2.0) | 5.9 (1.2) | 8.5 (2.1) | 6.0 (1.2) | 7.3 (1.6) | 5.9 (1.2) |
| Maternal ethnicity, n (%) | ||||||
| South Asian | 81 (60.9) | 218 (47.7) | 81 (100) | 218 (100) | 0 (0) | 0 (0) |
| White European | 52 (39.1) | 239 (52.3) | 0 (0) | 0 (0) | 52 (100) | 239 (100) |
| Physical activity during pregnancy, n (%) | ||||||
| Sedentary | 24 (18.0) | 79 (17.3) | 17 (21.0) | 49 (22.5) | 7 (13.5) | 30 (12.6) |
| Mild | 79 (59.4) | 266 (58.2) | 46 (56.8) | 127 (58.3) | 33 (63.5) | 139 (58.2) |
| Moderate | 29 (21.8) | 108 (23.6) | 18 (22.2) | 41 (18.8) | 11 (21.2) | 67 (28.0) |
| Strenuous | 1 (0.8) | 4 (0.9) | 0 (0) | 1 (0.5) | 1 (1.9) | 3 (1.3) |
| Social disadvantage index, n (%)* | ||||||
| High | 11 (8.3) | 36 (7.9) | 8 (9.9) | 31 (14.2) | 3 (5.8) | 5 (2.1) |
| Moderate | 34 (25.6) | 89 (19.5) | 24 (29.6) | 65 (29.8) | 10 (19.2) | 24 (10.0) |
| Low | 68 (51.1) | 270 (59.1) | 33 (40.7) | 96 (44.0) | 35 (67.3) | 174 (72.8) |
| Unknown | 20 (15.0) | 62 (13.6) | 16 (19.8) | 26 (11.9) | 4 (7.7) | 36 (15.1) |
| Smoking history, n (%) | ||||||
| Never smoked | 107 (80.5) | 376 (82.3) | 81 (100) | 218 (100) | 26 (50.0) | 158 (66.1) |
| Quit before pregnancy | 11 (8.3) | 35 (7.7) | 0 (0.0) | 0 (0.0) | 11 (21.2) | 35 (14.6) |
| Quit during pregnancy | 11 (8.3) | 32 (7.0) | 0 (0.0) | 0 (0.0) | 11 (21.2) | 32 (13.4) |
| Current smoker | 3 (2.3) | 10 (2.2) | 0 (0.0) | 0 (0.0) | 3 (5.8) | 10 (4.2) |
| Unknown | 1 (0.8) | 4 (0.9) | 0 (0.0) | 0 (0.0) | 1 (1.9) | 4 (1.7) |
| Diet quality index, mean (SD) | 5.4 (7.2) | 4.1 (8.0) | 7.8 (6.9) | 6.9 (8.5) | 1.7 (6.2) | 1.5 (6.6) |
| Protein, mean (SD), % of total energy | 16.4 (2.8) | 16.1 (2.6) | 16.1 (2.7) | 15.7 (2.4) | 16.9 (2.8) | 16.5 (2.6) |
| Plant protein, mean (SD), % of energy | 6.3 (1.8) | 5.9 (1.7) | 7.2 (1.5) | 7.1 (1.4) | 4.8 (1.2) | 4.9 (1.2) |
| Animal protein, mean (SD), % of energy | 9.7 (3.3) | 9.8 (3.1) | 8.7 (3.2) | 8.4 (2.9) | 11.4 (2.8) | 11.1 (2.7) |
*The social disadvantage index was constructed based on the sum of scores from household income, marital status, and employment status, and was previously validated.41 For income: 2 points were given if household income was <$30 000, 1 point if between $30 000 and $50 000, and 0 point if >$50 000. If married or common law 0 point was given, while 1 point was given if widowed, separated, divorced, or never married. If unemployed or retired 2 points were given, if employed 0 point was given. If the sum of points from household income, marital status, and employment status was 0–1 point participants were considered to have low disadvantage index, if 2–3 points moderate disadvantage index, and 4–5 points as high disadvantage index.
BMI, body mass index; FAMILY, Family Atherosclerosis Monitoring in Early Life; GDM, gestational diabetes mellitus; GTT, glucose tolerance test; IADPSG, International Association of the Diabetes and Pregnancy Study Groups; START, South Asian Birth Cohort.