TABLE 1.
PCBs (μg/g lipid) |
DDE (μg/g lipid) |
|||||||
Characteristics | <0.90 | 0.90–1.65 | >1.65 | P | <0.40 | 0.40–0.77 | >0.77 | P |
Girls (%) | 47.2 | 48.7 | 47.7 | 0.95 | 47.7 | 48.7 | 47.2 | 0.95 |
Birth weight (g) | 3719 ± 5132 | 3758 ± 497 | 3708 ± 465 | 0.58 | 3718 ± 497 | 3729 ± 502 | 3738 ± 478 | 0.92 |
BMI (kg/m2) | ||||||||
5 y of age | 16.0 ± 1.4 | 16.0 ± 1.3 | 15.9 ± 1.3 | 0.71 | 16.0 ± 1.4 | 16.0 ± 1.3 | 16.0 ± 1.4 | 0.93 |
7 y of age | 16.5 ± 1.8 | 16.6 ± 2.0 | 16.6 ± 1.9 | 0.85 | 16.6 ± 1.8 | 16.6 ± 2.0 | 16.6 ± 1.9 | 0.97 |
Change in BMI from 5 to 7 y of age (kg/m2) | 0.44 ± 1.0 | 0.68 ± 1.2 | 0.69 ± 1.1 | 0.07 | 0.53 ± 1.0 | 0.62 ± 1.2 | 0.67 ± 1.1 | 0.54 |
Waist circumference (cm) | 60.8 ± 4.7 | 61.6 ± 5.1 | 61.7 ± 5.0 | 0.19 | 61.1 ± 4.9 | 61.5 ± 5.2 | 61.6 ± 4.8 | 0.53 |
Maternal age at child's birth (y) | 27.1 ± 4.7 | 29.4 ± 5.0 | 31.3 ± 4.8 | <0.001 | 27.5 ± 5.1 | 29.0 ± 4.7 | 31.2 ± 4.9 | <0.001 |
Maternal prepregnancy BMI (kg/m2) | 23.9 ± 3.9 | 23.6 ± 3.7 | 24.3 ± 4.5 | 0.18 | 23.2 ± 3.7 | 23.8 ± 3.8 | 24.8 ± 4.5 | 0.001 |
Maternal weight gain during pregnancy (kg) | 15.3 ± 5.0 | 15.1 ± 5.1 | 14.4 ± 8.1 | 0.35 | 15.4 ± 4.8 | 15.0 ± 5.1 | 14.3 ± 8.3 | 0.19 |
PCBs and DDE at 5 y of age (μg/g lipid)3 | 0.79 ± 0.5 | 1.37 ± 0.8 | 2.41 ± 1.7 | <0.001 | 0.30 ± 0.2 | 0.57 ± 0.4 | 1.35 ± 1.1 | <0.001 |
Parity (%)4 | 68.5 | 73.9 | 80.7 | 0.03 | 71.0 | 71.7 | 80.5 | 0.07 |
SES (high/intermediate/low) (%) | 22/25/53 | 25/26/49 | 26/31/43 | 0.35 | 23/25/52 | 24/26/50 | 27/31/42 | 0.23 |
Maternal alcohol consumption during pregnancy (%) | 15.4 | 11.8 | 14.4 | 0.57 | 14.9 | 13.8 | 12.8 | 0.84 |
Maternal smoking during pregnancy (%) | 24.6 | 32.8 | 29.7 | 0.20 | 30.3 | 27.7 | 29.2 | 0.85 |
No good conditions for playing outdoors (%)5 | 16.5 | 18.2 | 13.2 | 0.40 | 16.7 | 19.0 | 12.2 | 0.18 |
PCB and DDE concentrations were measured in maternal serum and log transformed. The PCB concentration was based on the sum of PCB congeners 138, 153, and 180. P values were determined by using ANOVA and Pearson's chi-square tests of differences across tertiles of PCB and DDE. DDE, p,p′-dichlorodiphenyldichloroethylene; PCB, polychlorinated biphenyl; SES, socioeconomic status.
Mean ± SD (all such values).
Fifty-nine missing values.
Percentage of women with pregnancies before the current one.
Twenty-six missing values.