Table 1.
Baseline Characteristics of Mothers Participating in the Vitamin D Antenatal Asthma Reduction Trial (N = 876)
| No. (%) of Participants | ||
|---|---|---|
| 4400 IU/d of Vitamin D (n = 440) | 400 IU/d of Vitamin D (n = 436) | |
| Age, mean (SD), y | 27.5 (5.5) | 27.3 (5.6) |
| Gestation age, mean (SD), wk | 14.1 (2.8) | 14.2 (2.7) |
| 25-Hydroxyvitamin D, mean (SD), ng/mLa | 23.3 (10.1) | 22.5 (10.1) |
| Mother | ||
| Asthma | 191 (43) | 167 (38) |
| Allergic rhinitis | 275 (63) | 283 (65) |
| Eczema | 139 (32) | 139 (32) |
| Maternal partner | ||
| Asthma | 108 (25) | 94 (22) |
| Allergic rhinitis | 173 (39) | 192 (44) |
| Eczema | 81 (18) | 63 (14) |
| Mother’s race/ethnicity | ||
| Black | 190 (43) | 190 (44) |
| White Hispanic | 59 (13) | 61 (14) |
| White non-Hispanic | 114 (26) | 116 (27) |
| Other | 77 (18) | 69 (16) |
| Educational status | ||
| <High school | 66 (15) | 42 (10) |
| High school or technical school | 123 (28) | 142 (33) |
| Some college | 108 (25) | 105 (24) |
| College graduate or graduate school | 143 (33) | 147 (34) |
| Marital status | ||
| Married | 191 (43) | 203 (47) |
| Divorced or separated | 13 (3) | 10 (2) |
| Not married | 236 (54) | 223 (51) |
| Household income, US $ | ||
| <30 000 | 132 (30) | 128 (29) |
| 30 000–49 999 | 62 (14) | 58 (13) |
| 50 000–74 999 | 50 (11) | 51 (12) |
| 75 000–99 999 | 42 (10) | 39 (9) |
| 100 000–149 000 | 35 (8) | 36 (8) |
| >150 000 | 18 (4) | 14 (3) |
| Refused to say or unknown | 101 (23) | 110 (25) |
SI conversion factor: To convert 25-hydroxyvitamin D from ng/mL to nmol/L, multiply by 2.496.
a
The 4400 vitamin D IU group included 437 women; 400 vitamin D IU group, 433 women.