Table 3.
Magnitudes of association among strain values ≤25th centile in each cervical region and spontaneous preterm delivery (<37 weeks)
| Cervical region Strain | Model I | Model II | |||
|---|---|---|---|---|---|
| OR | 95% CI | OR | 95% CI | ||
| Internal os endocervical | |||||
| ≤ 0.19 | 0.2 | 0.03–0.96 | 0.2 | 0.04–0.9 | |
| > 0.19 | 1 | Reference | 1 | Reference | |
| Internal os entire cervix | |||||
| ≤ 0.14 | 0.17 | 0.03–0.9 | 0.17 | 0.03–0.9 | |
| > 0.14 | 1 | Reference | 1 | Reference | |
| Sagittal endocervical | |||||
| ≤ 0.25 | 0.8 | 0.3–2.2 | 0.9 | 0.3–2.5 | |
| > 0.25 | 1 | Reference | 1 | Reference | |
| Sagittal entire cervix | |||||
| ≤ 0.2 | 0.7 | 0.2–2.0 | 0.8 | 0.3–2.4 | |
| > 0.2 | 1 | Reference | 1 | Reference | |
| External os endocervical | |||||
| ≤ 0.35 | 1.2 | 0.4–3.3 | 1.3 | 0.5–4.0 | |
| > 0.35 | 1 | Reference | 1 | Reference | |
| External os entire cervix | |||||
| ≤ 0.26 | 1.6 | 0.6–4.2 | 1.7 | 0.6–4.5 | |
| > 0.26 | 1 | Reference | 1 | Reference | |
Model I adjusted for gestational age at examination; Model II adjusted for gestational age at examination, race, smoking status, parity, maternal age, pre-pregnancy body mass index, and prior preterm delivery.