Table 1.
Characteristics of I-KIDS women in analytic sample.
| Full samplea (n = 531) | Analytic sampleb (n = 302) | Women carrying females (n = 155) | Women carrying males (n = 147) | |
|---|---|---|---|---|
|
| ||||
| Characteristic | n (%) | |||
| Race/ethnicity | ||||
| Non-Hispanic White (ref) | 424 (80.0) | 246 (81.5) | 124 (80.0) | 122 (83.0) |
| Others | 106 (20.0) | 56 (18.5) | 31 (20.0) | 25 (17.0) |
| Education | ||||
| Some college or less (ref) | 103 (19.4) | 51 (16.9) | 21 (13.5) | 30 (20.4) |
| College graduate or higher | 428 (80.6) | 251 (83.1) | 134 (86.5) | 117 (79.6) |
| Ever smoker | ||||
| No (ref) | 435 (82.2) | 250 (82.8) | 123 (79.4) | 127 (86.4) |
| Yes | 94 (17.8) | 52 (17.2) | 32 (20.6) | 20 (13.6) |
| Parity | ||||
| No children (ref) | 272 (51.3) | 163 (54.0) | 83 (53.5) | 80 (54.4) |
| 1 + children | 258 (48.7) | 139 (46.0) | 72 (46.5) | 67 (45.6) |
| Fetal sex | ||||
| Male (ref) | 271 (51.1) | 147 (48.7) | - | - |
| Female | 259 (48.9) | 155 (51.3) | - | - |
| Median (25th, 75th percentile) | ||||
| Maternal age (years) | 30.0 (27.1, 32.7) | 30.4 (27.5, 32.8) | 30.5 (27.9, 32.7) | 30.3 (27.8, 32.9) |
| Pre-pregnancy BMI (kg/m2) | 24.6 (21.9, 29.4) | 24.7 (21.9, 28.9) | 24.4 (21.6, 28.2) | 25.0 (22.5, 30.3) |
| Early pregnancy Alternative Healthy Eating Index 2010*‡ | 51.5 (43.9, 59.7) | 51.7 (44.6, 59.3) | 53.2 (45.8, 61.8) | 50.1 (43.4, 57.8) |
| Early pregnancy perceived stress | 10.9 (6.9, 16.1) | 11.1 (7.1, 16.5) | 11.5 (7.2, 16.9) | 10.5 (6.9, 16.1) |
| Gestational age at blood collection | 16.9 (16.3, 17.7) | 16.9 (16.3, 17.6) | 16.8 (16.3, 17.7) | 17.0 (16.3, 17.6) |
Percentages may not add up to 100% due to missing (n missing): perceived stress score (8 missing in reference population; 2 missing in analytic sample), gestational age (1 missing in reference population).
*
Alcohol intake was removed from the index (total score out of 100).
‡
Median (25th, 75th percentile) Alternative Healthy Eating Index 2010 excludes women whose diet data have not yet been analyzed (n = 49).
a
Women with at least one chemical biomarker.
b
Women with all chemical biomarkers and at least one hormone measurement. BMI, body mass index; I-KIDS, Illinois Kids Development Study.