Table 2 Risk factors at the index pregnancy for recurrent preterm birth at the subsequent delivery
   Factor | Odds Ratio ( 95% confidence interval) |
|---|---|
Spontaneous preterm birth | 4.38 (3.71-5.17) |
Preterm placenta previa | 3.60 (1.52-8.51) |
Preterm severe preeclampsia | 2.82 (1.66-4.78) |
Preterm IUGR | 1.48 (1.003-2.18) |
Severe preeclampsia | 1.56 (1.01-2.53) |
IUGR | 1.52 (1.18-1.96) |
Placenta previa | 0.71 (.33-1.54) |
Maternal age | 1.03 (1.01-1.04) |