Table 3.
Regression coefficients between maternal log10 urine perchlorate concentrations (µg/L) and birthweight (grams) in the study population of pregnant women from San Diego County 2000–2003
| Both sexes
|
Males
|
Females
|
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Group | N | β1 | SE | p | N | β1 | SE | p | N | β1 | SE | p |
| All | 1957 | 51.3 | 39.7 | 0.20 | 959 | 143.1 | 56.3 | 0.01 | 998 | −38.3 | 56.0 | 0.49 |
| Urinary iodide2 | ||||||||||||
| <100 µg/L | 629 | 87.2 | 68.2 | 0.20 | 313 | 177.3 | 91.7 | 0.05 | 316 | −14.8 | 102.1 | 0.88 |
| 100–300 µg/L | 920 | −34.7 | 57.8 | 0.55 | 444 | 25.4 | 84.6 | 0.76 | 476 | −84.6 | 79.6 | 0.29 |
| >300 µg/L | 408 | 185.2 | 113.3 | 0.10 | 202 | 301.1 | 161.5 | 0.06 | 206 | −1.1 | 160.1 | 0.99 |
| Gestational age | ||||||||||||
| <37 weeks | 158 | 547.3 | 202.6 | 0.01 | 85 | 829.1 | 263.1 | <0.001 | 73 | 230.4 | 319.1 | 0.47 |
| ≥37 weeks | 1799 | 28.8 | 36.0 | 0.42 | 874 | 97.3 | 51.5 | 0.06 | 925 | −39.5 | 50.2 | 0.43 |
| Mothers | birthplace | |||||||||||
| Mexico | 933 | 27.1 | 53.1 | 0.61 | 451 | 29.9 | 72.6 | 0.68 | 482 | 26.0 | 77.8 | 0.74 |
| US born | ||||||||||||
| All | 882 | 95.3 | 63.0 | 0.13 | 445 | 297.2 | 91.9 | <0.001 | 437 | −95.1 | 86.4 | 0.27 |
| White | 381 | 166.7 | 104.9 | 0.11 | 204 | 325.6 | 151.4 | 0.03 | 177 | −34.8 | 144.7 | 0.81 |
| Hispanic | 394 | 40.4 | 94.7 | 0.67 | 186 | 305.4 | 136.9 | 0.03 | 208 | −186.0 | 129.3 | 0.15 |
| Other | 107 | 137.3 | 144.4 | 0.34 | 55 | 408.3 | 202.5 | 0.05 | 52 | −43.2 | 184.2 | 0.82 |
| Other birthplace | 142 | −39.0 | 167.9 | 0.82 | 63 | 23.8 | 255.6 | 0.93 | 79 | −115.8 | 237.1 | 0.63 |
Abbreviations: β, regression coefficient; N, sample size; SE, standard error
Adjusted for urinary creatinine (log10), maternal age, maternal weight, race, and sex
Urinary iodide concentrations were not corrected for urinary creatinine concentrations