Table 3. Classification of rate of preterm birth recurrence by clinical subtypes and gestational age categories (N = 5946).
| Current preterm birth categories | |||||
|---|---|---|---|---|---|
| Total | Term | Preterm | sPTB | mPTB | |
| N | n (%) | n (%) | n (%) | n (%) | |
| Previous Preterm deliveries | |||||
| Term delivery | 5,405 | 4880 (90.3) | 525 (9.7) | 330 (6.1) | 195 (3.6) |
| Preterm delivery | 541 | 409 (75.6) | 132 (24.4) | 73 (13.5) | 59 (10.9) |
| Spontaneous delivery | 4,309 | 3863 (89.6) | 446 (10.4) | 358 (8.3) | 88 (2.1) |
| Medically indicated delivery | 1,619 | 1408 (87.9) | 211 (13.1) | 45 (2.8) | 166 (10.3) |
| Early preterm birth | 61 | 45 (73.8) | 16 (26.2) | 10 (16.4) | 6 (9.8) |
| Spontaneous delivery | 45 | 35 (77.8) | 10 (22.2) | 9 (20) | 1 (2.2) |
| Medically indicated delivery | 16 | 10 (62.5) | 6 (37.6) | 1 (6.3) | 5 (31.3) |
| Late preterm birth | 480 | 364 (75.8) | 116 (24.2) | 63 (13.1) | 53 (11) |
| Spontaneous delivery | 314 | 246 (78.3) | 68 (21.7) | 52 (16.6) | 16 (5.1) |
| Medically indicated delivery | 163 | 115 (70.6) | 48 (29.4) | 11 (6.7) | 37 (22.7) |