Table 2.
Risk and relative risk of preterm birth by chorioamnionitis and fetal vasculitis exposure groups.
| Exposure Group | N | Preterm Birth, n (%) | Unadjusted RR & 95% CI | Adjusteda RR & 95% CI |
|---|---|---|---|---|
| Subclinical Chorioamnionitis | 336 | 62 (18.5) | 0.83 (0.64, 1.07) | 0.92 (0.71, 1.20) |
| Clinical Chorioamnionitisb | 59 | 10 (17.0) | 0.76 (0.43, 1.36) | 0.81 (0.44, 1.50) |
| Clinical Chorioamnionitis with Histologic Confirmation | 45 | 7 (15.6) | 0.70 (0.35, 1.40) | 0.82 (0.40, 1.69) |
| No Clinical or Subclinical Chorioamnionitis (Reference) | 976 | 217 (22.2) | - | - |
|
| ||||
| Histologic Chorioamnionitis with Fetal Vasculitis | 155 | 36 (23.2) | 1.04 ( 0.76, 1.41) | 1.17 (0.84, 1.64) |
| Histologic Chorioamnionitis without Fetal Vasculitis | 226 | 33 (14.6) | 0.65 (0.47, 0.91) | 0.73 (0.52, 1.03) |
| No Histologic Chorioamnionitis (Reference) | 979 | 219 (22.4) | - | - |
Abbreviations: RR, relative risk; CI, confidence interval.
a
Adjusted for maternal age, race, ethnicity, parity, diabetes or gestational diabetes, hypertension or preeclampsia.
b
With or without histologic chorioamnionitis.