Table 1.
Demographic Characteristics of Participants According to Prenatal Blood Lead Levels in Mexico Citya
| Prenatal Blood Lead Level | |||
|---|---|---|---|
| Overall (n = 369) | ≥5 µg/dL (n = 171) | <5 µg/dL (n = 198) | |
| Mean (SD) or N (%) | Mean (SD) or N (%) | Mean (SD) or N (%) | |
| Child characteristics | |||
| Age, yb | 13.7 (1.9) | 14.4 (2.0) | 13.1 (1.6) |
| Female | 186 (50.4%) | 87 (50.9%) | 99 (50.0%) |
| BMI z score | 0.6 (1.2) | 0.5 (1.3) | 0.6 (1.2) |
| No. siblings at birth | 2.0 (1.0) | 2.0 (1.0) | 2.0 (1.0) |
| Maternal characteristics | |||
| Maternal age, y | 26.7 (5.6) | 26.9 (5.9) | 26.4 (5.3) |
| Maternal education, y | 11.0 (2.9) | 10.9 (2.9) | 11.0 (3.0) |
| Marital status | |||
| Yes | 266 (72.1%) | 130 (76.0%) | 136 (68.7%) |
| No | 103 (27.9%) | 41 (24.0%) | 62 (31.3%) |
| Smoking history | |||
| Ever | 181 (50.3%) | 84 (50.9%) | 97 (49.7%) |
| Never | 179 (49.7%) | 81 (49.1%) | 98 (50.3%) |
Abbreviations: BMI, body mass index; SD, standard deviation.
aMissing information: maternal smoking history (n = 9).
bStudent t test with P value ≤ 0.05.