Table 5. Risk of postpartum hemorrhage (PPH>500ml) due to dystocia in second deliveries without previous cesarean section (CS) (reference), second deliveries with previous CS, and first deliveries; singleton births, ≥22 weeks of gestation and spontaneous onset or induction of labor.
| Total | Dystocia related PPH | |||||
|---|---|---|---|---|---|---|
| Groups | (n) | (n) | % | aOR | 95% CI | |
| 2nd delivery without previous CS | 864751 | 3146 | 0.4 | 1 | Ref | |
| 2nd delivery with previous CS | 71240 | 3692 | 5.2 | 18.85 | 17.84 | 19.92 |
| 1st delivery | 1124388 | 28690 | 2.6 | 9.10 | 8.72 | 9.48 |
CI confidence interval, aOR OR adjusted for maternal age and period (1967–1977, 1978–1987, 1988–1997, 1998–2007 and 2008–2017).