Table 1.
Characteristics of the study participants in the included cohorts.
| Cohort | Units | INMA | KOREA | VIVA | SAPPORO-HOKKAIDO | ALSPAC | MoBa | RHEA |
|---|---|---|---|---|---|---|---|---|
|
| ||||||||
| Country | Spain | Korea | United States | Japan | United Kingdom | Norway | Greece | |
| Main ethnicity | ||||||||
| European | % | 90 | 76 | 100 | 95.8 | 100 | ||
| Asian | % | 100 | 3.3 | 100 | 2.8 | |||
| African | % | 8.6 | ||||||
| Other | % | 10 | 11.8 | 1.4 | ||||
| Prenatal THg matrix | Cord blood | Maternal blood | Maternal blood | Maternal hair | Maternal blood | Maternal blood | Maternal blood | |
| Cord THg* | GM (CI95%), μg/L | 8.70 (8.24, 9.19) | 5.33 (5.19, 5.47) | 5.74 (5.16, 6.39) | 9.30 (6.18–12.42) | 2.01 (0.79, 4.89) | 6.02 (5.72, 6.35) | 7.13 (6.71, 7.59) |
| N children with cord THg + cord blood DNA methylation | N | 304 | 329 | 338 | 268 | 223 | No | No |
| N children with blood THg + blood DNA methylation | N | 182 | No | No | No | 312 | 192 | 197 |
| Maternal age | Mean (SD), years | 30.4 (4.1) | 30.4 (3.6) | 32.7 (4.9) | 30.1 (5.0) | 29.4 (4.3) | 32.8 (3.7) | 30.8 (4.8) |
| Parity | % nulliparous | 37.1 | 56.5 | 49.7 | 46.3 | 49.3 | 52.8 | 60.0 |
| Child sex | % male | 51.2 | 48.0 | 52.1 | 45.5 | 47.1 | 53.7 | 55.5 |
| Maternal education | ||||||||
| Up to primary | % | 26.8 | 22.2 | 5.6 | 3.3 | 8.1 | 0 | 4.6 |
| Secondary | % | 42.4 | 16.4 | 22.3 | 41.0 | 68.6 | 20.1 | 55.8 |
| University | % | 307 | 61.4 | 71.9 | 55.5 | 23.3 | 79.9 | 39.6 |
| Smoking during pregnancy | %, yes | 29.2 | 10.9 | 11.5 | 16.4 | 17.9 | 4.4 | 21.2 |
| Fish consumption | Mean (SD), servings/week | 5.0 (2.3) | 4.2 (4.1) | 0.2 (0.2) | 3.5 (5.0) | 0.2 (0.2) | 5.9 (7.9) | 1.2 (0.9) |
| Correlation with Cord log2THg | Spearman coefficient | 0.30 | 0.16 | 0.46 | 0.22 | 0.31 | 0.31 | 0.18 |
GM: geometric mean; THg: total mercury;
*
Hg cord blood (μg/L) = 1.7*Hg maternal blood (μg/L); Hg in whole blood (μg/mL) = 250* maternal hair (μg/g).