Table 3 Summary of gestational age at each time of ultrasound measurement
From: Maternal exposure to ambient fine particulate matter and fetal growth in Shanghai, China
Ultrasound measurements | Summary of gestational age | |||
|---|---|---|---|---|
Mean | Std. Dev | Freq | Rang | |
1st | 19.96 | 5.15 | 7965 | 13.5~40.0 |
2nd | 25.48 | 4.28 | 7269 | 13.6~40.6 |
3rd | 30.93 | 4.25 | 6280 | 14.1~40.4 |
4th | 34.91 | 3.55 | 4701 | 15.2~40.6 |
5th | 36.97 | 3.04 | 2540 | 14.1~40.7 |
6th | 37.69 | 2.91 | 850 | 14.0~40.9 |
7th | 37.59 | 3.28 | 235 | 14.3~40.6 |
8th | 37.35 | 3.32 | 55 | 24.0~40.6 |
9th | 37.25 | 3.37 | 21 | 28.6~40.6 |
10th | 37.44 | 2.17 | 10 | 32.4~40.4 |
Total | 28.09 | 7.54 | 29,926 | 13.5~40.9 |