| Attributes |
Levels |
| cervical length measurement |
none |
| |
abdominal ultrasound |
| |
vaginal ultrasound |
| progesterone administration |
none |
| |
oral administration |
| |
vaginal administration |
| risk of short term health care problems due to prematurity |
2% |
| |
4% |
| |
8% |
| risk of long term health care problems due to prematurity |
<5% |
| |
5-10% |
| |
>10% |
|