Table 2 Average PM2.5 levels (μg/m3) during pregnancy in Shanghai Birth Cohort (N = 2332)
|  | All subjects N = 2332 | Male N = 1186 | Female N = 1146 | |||
|---|---|---|---|---|---|---|
Period | Mean (SD) | Median (IQR) | Mean (SD) | Median (IQR) | Mean (SD) | Median (IQR) |
Full pregnancy | 50 (5) | 50 (7) | 50 (5) | 50 (7) | 50 (5) | 50 (7) |
First trimester | 53 (13) | 51 (23) | 52 (13) | 51 (22) | 53 (13) | 52 (23) |
Second trimester | 49 (13) | 45 (17) | 49 (13) | 45 (18) | 49 (12) | 45 (17) |
Third trimester | 48 (12) | 45 (18) | 48 (12) | 45 (18) | 48 (13) | 43 (18) |