Table 2.
Predictors for recurrence risk of preterm birth by maternal characteristics in the first pregnancy
| Maternal characteristics** | N | Preterm birth in subsequent pregnancies | |||
|---|---|---|---|---|---|
| n (%) | RR (95% CI)* | Perinatal death n (%) N = 126 | P-value | ||
| Gestational age | |||||
| Preterm birth | 578 | 100 (17.3) | 2.7 (2.1–3.4) | 15 (15.0) | <0.001 |
| Term birth | 3289 | 202 (6.1) | Reference | 11 (5.4) | |
| Pre-eclampsia | |||||
| Yes | 152 | 26 (17.1) | 2.5 (1.7–3.7) | 5 (17.9) | <0.001 |
| No | 3715 | 276 (7.4) | Reference | 21 (8.5) | |
| Perinatal death | |||||
| Yes | 296 | 55 (18.6) | 2.6 (1.9–3.5) | 9 (16.4) | <0.001 |
| No | 3571 | 247 (6.9) | Reference | 15 (6.1) | |
| Low birth weight | |||||
| Yes | 592 | 106 (17.9) | 2.9 (2.3–3.6) | 21 (19.8) | <0.001 |
| No | 3275 | 197 (6.0) | Reference | 6 (3.0) | |
| Caesarean section | |||||
| Yes | 1238 | 111 (8.9) | 1.2 (0.9–1.5) | 8 (7.2) | 0.13 |
| No | 2629 | 191 (7.3) | Reference | 18 (9.4) | |
| Induced labour | |||||
| Yes | 1514 | 101 (6.7) | 0.8 (0.6–1.0) | 9 (8.9) | 0.1 |
| No | 2353 | 201 (8.5) | Reference | 17 (8.5) | |
RR, adjusted relative risk; CI, confidence interval.
*
Adjusted for maternal age and maternal education in log-binomial model accounting for correlation between successive deliveries of the same mother.
**
indicates maternal characteristics in the first pregnancy.