Table III.
Reproductive history for risk groups
| PTB-S vs PTB-M | |||||
|---|---|---|---|---|---|
| Risk group | Subtypes | OR | 95% CI | P | |
| Multigravidity without previous outcome adverse | PTB-S | 1.00 | - | - | - | 
| Primigravidity | PTB-M | 1.07 | 0.76 | 1.51 | 0.692 | 
| Previous preterm birth alone | PTB-M | 0.84 | 0.55 | 1.28 | 0.413 | 
| Previous miscarriage alone | PTB-M | 0.88 | 0.59 | 1.32 | 0.550 | 
| Previous preterm + miscarriage | PTB-M | 0.78 | 0.47 | 1.27 | 0.313 | 
|  | |||||
| PTB-I vs PTB-PPROM | |||||
|  | |||||
| Risk group | Subtypes | OR | 95% CI | P | |
|  | |||||
| Multigravidity without previous outcome adverse | PTB-PPROM | 1.00 | - | - | - | 
| Primigravidity | PTB-I | 1.43 | 1.02 | 2.02 | 0.039* | 
| Previous preterm birth alone | PTB-I | 1.80 | 1.15 | 2.80 | 0.010* | 
| Previous miscarriage alone | PTB-I | 1.10 | 0.73 | 1.66 | 0.647 | 
| Previous preterm + miscarriage | PTB-I | 1.07 | 0.63 | 1.81 | 0.793 | 
Note: PTB-S, spontaneous preterm birth; PTB-I, preterm labor leading to PTB (idiopathic); PTB-PPROM, premature rupture of membranes ; PTB-M, medically indicated iatrogenic PTB.
P value < 0.05