Table 1.
Characteristics of women living < 5 km away from an AQMS and their associations with NO2 levels averaged during pregnancy (n = 776).
| Mean (median) NO2 level (μg/m3) |
|||||
|---|---|---|---|---|---|
| Characteristic | n (%) | Nearest-AQMS model | p-Valuea | TAG model | p-Valuea |
| Sex of offspring | 0.97 | 0.28 | |||
| Male | 395 (51) | 28.6 (32.3) | 23.6 (23.8) | ||
| Female | 381 (49) | 28.6 (32.5) | 23.9 (23.9) | ||
| Gestational duration (weeks) | 0.37 | 0.17 | |||
| 30–36 | 48 (6) | 30.2 (33.4) | 24.7 (23.1) | ||
| 37–38 | 151 (20) | 29.1 (32.6) | 24.3 (24.1) | ||
| 39–40 | 407 (52) | 28.1 (32.2) | 23.4 (23.6) | ||
| ≥ 41 | 170 (22) | 29.2 (32.8) | 23.8 (24.3) | ||
| Birth order | 0.71 | 0.14 | |||
| First birth | 367 (47) | 28.8 (33.4) | 23.9 (23.9) | ||
| Second birth | 263 (34) | 28.7 (31.7) | 23.9 (24.0) | ||
| Third birth or more | 145 (19) | 28.0 (32.2) | 23.0 (23.1) | ||
| Missing value | 1 | ||||
| Trimester of conception of the child | < 10−4 | < 10−4 | |||
| January–March | 167 (21) | 25.7 (25.3) | 21.5 (21.9) | ||
| April–June | 184 (24) | 29.1 (33.6) | 23.5 (24.0) | ||
| July–September | 226 (29) | 31.2 (35.2) | 25.9 (25.7) | ||
| October–December | 199 (26) | 27.7 (31.3) | 23.3 (23.5) | ||
| Maternal age at conception (years) | < 10−2 | < 10−2 | |||
| < 25 | 187 (24) | 26.7 (26.3) | 22.8 (22.7) | ||
| 25–29 | 289 (37) | 30.0 (33.8) | 24.3 (24.3) | ||
| 30–34 | 203 (26) | 28.7 (32.1) | 24.2 (24.0) | ||
| ≥ 35 | 97 (13) | 27.9 (32.3) | 22.9 (23.4) | ||
| Maternal height (cm) | 0.64 | 0.44 | |||
| < 160 | 188 (24) | 28.3 (32.0) | 23.4 (24.0) | ||
| 160–169 | 460 (60) | 28.6 (32.7) | 23.8 (23.8) | ||
| ≥ 170 | 121 (16) | 29.4 (33.1) | 24.2 (24.2) | ||
| Missing value | 7 | ||||
| Maternal prepregnancy weight (kg) | 0.33 | 0.46 | |||
| < 50 | 83 (11) | 27.7 (28.8) | 24.3 (24.1) | ||
| 50–59 | 333 (43) | 28.6 (32.3) | 23.8 (23.8) | ||
| 60–69 | 211 (27) | 29.4 (33.5) | 23.8 (24.0) | ||
| 70–79 | 87 (11) | 29.0 (33.0) | 23.6 (23.8) | ||
| ≥ 80 | 60 (8) | 26.6 (25.9) | 22.7 (22.0) | ||
| Missing value | 2 | ||||
| Body mass index before pregnancy (kg/m2) | 0.39 | 0.07 | |||
| < 18.5 | 82 (11) | 29.6 (34.3) | 25.0 (24.7) | ||
| 18.5–24.9 | 512 (67) | 28.5 (32.1) | 23.8 (23.9) | ||
| 25–29.9 | 111 (14) | 29.4 (33.7) | 23.3 (23.4) | ||
| ≥ 30 | 62 (8) | 27.1 (30.6) | 23.0 (22.4) | ||
| Missing value | 9 | ||||
| Center | < 10−4 | < 10−4 | |||
| Poitiers | 316 (41) | 24.9 (18.8) | 20.3 (19.2) | ||
| Nancy | 460 (59) | 31.2 (34.4) | 26.1 (25.7) | ||
| Maternal age at end of education (years) | 0.02 | < 10−3 | |||
| ≤ 16 | 52 (7) | 29.6 (33.1) | 24.0 (23.6) | ||
| 17–18 | 104 (13) | 27.0 (29.6) | 22.2 (21.9) | ||
| 19–20 | 124 (16) | 27.1 (29.1) | 23.2 (23.0) | ||
| 21–22 | 165 (21) | 27.9 (30.0) | 23.3 (23.5) | ||
| 23–24 | 174 (22) | 29.3 (33.1) | 24.5 (24.6) | ||
| ≥ 25 | 157 (20) | 30.6 (34.5) | 24.7 (24.6) | ||
| Maternal active smoking (second trimester) | 0.45 | 0.30 | |||
| No | 641 (83) | 28.8 (32.7) | 23.8 (24.0) | ||
| Yes | 133 (17) | 28.1 (32.0) | 23.3 (22.8) | ||
| Missing value | 2 | ||||
| Maternal passive smoking (second trimester) | 0.48 | 0.53 | |||
| No | 507 (66) | 28.5 (32.1) | 23.7 (23.9) | ||
| Yes | 264 (34) | 29.0 (33.3) | 23.9 (23.6) | ||
| Missing value | 5 | ||||
a
p-Value comparing model-specific exposure estimates between categories (Student test for dichotomous variables) or among categories (Fisher’s analysis of variance for variables with more than two categories). Tests were performed without including missing data as a separate category.