Table 3.
Risk of premature low birth weight associated with maternal urinary lead levels, stratified by maternal age.
| Pb levelsa | < 29 years (n = 200) |
≥ 29 years (n = 208) |
P for heterogeneity | ||||
|---|---|---|---|---|---|---|---|
| Ca/Co | ORb (95% CI) | ORc (95% CI) | Ca/Co | ORb (95% CI) | ORc (95% CI) | ||
| T1 | 12/50 | 1.00 | 1.00 | 11/52 | 1.00 | 1.00 | 0.94 |
| T2 | 15/50 | 1.32 (0.53-3.28) | 1.56 (0.54-4.56) | 17/52 | 1.60 (0.66-3.86) | 1.71 (0.66-4.45) | |
| T3 | 23/50 | 1.93 (0.85-4.39) | 2.58 (1.00-6.73) | 24/52 | 2.37 (1.01-5.57) | 2.97 (1.07-8.23) | |
| p for trend | 0.10 | 0.05 | 0.05 | 0.04 | |||
Abbreviations: ca/co, numbers of cases and controls; CI, confidence interval; OR, odds ratio; T, tertile.
a
Lead levels (μg/Pb g creatinine): age < 29 years, T1 (< 4.92), T2 (4.92-10.03), T3 (≥ 10.04); age ≥ 29 years, T1 (< 6.33), T2 (6.33-13.08), T3(≥ 13.09).
b
Crude odds ratio.
c
Adjusted for household income, maternal body mass index, parity, passive smoking, and hypertension.