Table 2.
Comparison of demographic and laboratory data among enrolled women, stratified by thyroid status
| n | Case mean | Control mean | Comparison (case vs. control) | P value (test) | |
|---|---|---|---|---|---|
| Matching variables | |||||
| Fetal sex male (%) | 99 | 46 | 46 | All pairs matched for fetal sex | 1.00 (McNemar's) |
| Primiparous (%) | 99 | 33 | 33 | All pairs match primiparous/multiparous | 1.00 (McNemar's) |
| Education (yr) | 99 | 14.1 | 14.1 | 81 pairs matched years | 1.00 (Wilcoxon) |
| Maternal age (yr) | 99 | 30.3 | 29.7 | Mean difference 0.60 (−0.02 to 1.21) | 0.06 (paired t) |
| Location in Mainea | 99 | 1.82 | 1.77 | 54 matched location | 0.62 (Wilcoxon) |
| Next sibling's age (yr) | 66 | 4.24 | 4.25 | Mean difference − 0.01 (− 0.95 to 0.94) | 0.98 (paired t) |
| Other demographic variables | |||||
| Child's age (yr) | 99 | 2.27 | 2.44 | Mean difference − 0.17 (− 0.22 to − 0.1) | <0.001 (paired t) |
| Maternal weight (kg) | 94/97 | 87.8 | 77.74 | Mean difference 11.0 (5.6 go 16.5) | <0.001 (paired t) |
| Gestational age (wk) | 99 | 17.3 | 16.8 | Mean difference 0.43 (0.13 to 0.73) | 0.006 (paired t) |
| BMI (kg/m2) | 89/95 | 32.9 | 28.5 | Mean difference 4.61 (2.59 to 6.64) | <0.001 (paired t) |
| Hollingshead score | 99 | 3.39 | 3.38 | 81 pairs within 1 (range 1 to 5) | 0.95 (Wilcoxon) |
| Home score | 99 | 35.8 | 36.1 | 45 pairs within 2 (range 25 to 41) | 0.36 (Wilcoxon) |
| Chemistry test results | |||||
| Free T4 (ng/dl) | 99 | 0.90 | 1.17 | Mean difference − 0.27 (− 0.28 to − 0.25) | <0.001 (paired t) |
| TSH (mIU/liter) | 99 | 1.39 | 1.29 | Mean log difference − 1.09 (− 1.26 to − 0.92) | <0.001 (paired t) |
| Total T4 (μg/dl) | 92 | 12.0 | 14.0 | Mean difference − 2.03 (− 2.88 to − 1.19) | <0.001 (paired t) |
| TPO antibody (percentile ≥35 IU/ml) | 92 | 14.1 | 10.1 | Mean difference 4.0 (−5.4 to 13.4) | 0.52 (McNemar's) |
a
The state was divided into southern, middle, and northern areas and coded 1, 2, and 3, respectively.