Table 1. Participant characteristics.
| Preconception | Baseline and late pregnancy+ | ||||
|---|---|---|---|---|---|
| Characteristic | Control (n = 857) | Intervention (n = 870) | Control (n = 287) | Intervention (n = 293) | |
| Sociodemographic | |||||
| Study site | UK | 229 (26.7%) | 232 (26.7%) | 92 (32.1%) | 97 (33.1%) |
| Singapore | 328 (38.3%) | 332 (38.2%) | 82 (28.6%) | 84 (28.7%) | |
| New Zealand | 300 (35.0%) | 306 (35.2%) | 113 (39.4%) | 112 (38.2%) | |
| Age, years | Mean (SD) | 30.6 (3.7) | 30.6 (3.7) | 30.2 (3.3) | 30.5 (3.4) |
| Ethnicity | White | 396 (46.2%) | 413 (47.5%) | 165 (57.5%) | 179 (61.1%) |
| Chinese | 220 (25.7%) | 238 (27.4%) | 73 (25.4%) | 72 (24.6%) | |
| South Asian | 60 (7.0%) | 61 (7.0%) | 15 (5.2%) | 15 (5.1%) | |
| Malay | 85 (9.9%) | 80 (9.2%) | 12 (4.2%) | 11 (3.8%) | |
| Other | 96 (11.2%) | 78 (9.0%) | 22 (7.7%) | 16 (5.5%) | |
| Household income# | Low income | 74 (9.3%) | 76 (9.4%) | 11 (4.0%) | 12 (4.3%) |
| Middle income | 344 (43.2%) | 354 (43.7%) | 114 (41.2%) | 114 (40.9%) | |
| High income | 378 (47.5%) | 380 (46.9%) | 152 (54.9%) | 153 (54.8%) | |
| Gynecological | |||||
| Parity | Nulliparous | 593 (69.2%) | 578 (66.4%) | 196 (68.3%) | 169 (57.7%) |
| Parous | 264 (30.8%) | 292 (33.6%) | 91 (31.7%) | 124 (42.3%) | |
| Lifestyle | |||||
| Alcohol intake (per week) | None | 271 (31.6%) | 265 (30.5%) | 61 (21.3%) | 65 (22.2%) |
| >0 to ≤2.5 units | 312 (36.4%) | 301 (34.6%) | 115 (40.1%) | 109 (37.2%) | |
| >2.5 units | 274 (32.0%) | 304 (34.9%) | 111 (38.7%) | 119 (40.6%) | |
| Smoking status | Never | 664 (77.7%) | 662 (76.3%) | 225 (78.7%) | 237 (80.9%) |
| Previous | 131 (15.3%) | 136 (15.7%) | 49 (17.1%) | 44 (15.0%) | |
| Active | 60 (7.0%) | 70 (8.1%) | 12 (4.2%) | 12 (4.1%) | |
| Instances of moderate/vigorous physical activity in past 7 days | Median (IQR) | 3 (2, 5) | 3 (1, 5) | 4 (2, 6) | 3 (2, 5) |
| BMI category## | Not overweight or obese | 400 (46.7%) | 432 (49.8%) | 158 (55.1%) | 163 (55.8%) |
| Overweight | 240 (28.0%) | 224 (25.8%) | 69 (24.0%) | 89 (30.5%) | |
| Obese | 216 (25.2%) | 212 (24.4%) | 60 (20.9%) | 40 (13.7%) | |
| Days between preconception baseline and post-supplementation sampling | Median (IQR) | 28 (23, 31) | 28 (23, 32) | 27 (22, 31) | 28 (23, 31) |
| Preconception baseline: Taking a multiple micronutrient supplement | No | 583 (68.6%) | 609 (70.2%) | 198 (69.0%) | 195 (66.6%) |
| Yes | 267 (31.4%) | 259 (29.8%) | 89 (31.0%) | 98 (33.4%) | |
Data presented as number (%) unless otherwise stated. Sample sizes do not always equal to 857/251 for control group and 870/261 for intervention group due to missing values.
+Based on all available data for individuals with any analyte at both baseline and late pregnancy.
#Low 1st–3rd decile, Middle 4th–7th decile, High 8th–10th decile.
##BMI categories: Not overweight or obese, Overweight, and Obese <25, 25–<30, and ≥30 kg/m2, respectively.
BMI, body mass index; IQR, interquartile range; SD, standard deviation.