| No PPH | PPH |  |  |
---|---|---|---|---|
n= 10351 (91.1%) | n= 1012 (8.9%) | Unadjusted OR’s | Adjusted OR’s* | |
Maternal characteristic | Â | Â | Â | Â |
 BMI†|  |  |  |  |
   18.5-24.9 | 6714 (64.9) | 524 (51.8) | 1.00 | 1.00 |
   25.0-29.9 | 2376 (22.9) | 255 (25.2) | 1.38 (1.18-1.61) | 1.20 (1.01-1.42) |
   ≥ 30.0 | 1261 (12.2) | 233 (23.0) | 2.37 (2.01-2.79) | 1.86 (1.51-2.28) |
 Age (y) |  |  |  |  |
   Less than 20 | 551 (5.3) | 38 (3.8) | 0.70 (0.49-0.98) | 0.77 (0.53-1.12) |
   20-29 | 4078 (39.4) | 405 (40.0) | 1.00 | 1.00 |
   30-34 | 3553 (34.3) | 336 (33.2) | 0.95 (0.82-1.11) | 0.94 (0.79-1.11) |
   ≥ 35 | 2169 (21.0) | 233 (23.0) | 1.08 (0.91-1.28) | 0.93 (0.77-1.14) |
 Ethnicity |  |  |  |  |
   European | 5573 (53.9) | 491 (48.5) | 1.00 | 1.00 |
   Maori | 765 (7.4) | 78 (7.7) | 1.16 (0.90-1.49) | 1.27 (0.95-1.69) |
   Pacific island | 881 (8.5) | 136 (13.5) | 1.75 (1.43-2.15) | 1.60 (1.25-2.06) |
   Asian | 2052 (19.8) | 227 (22.4) | 1.26 (1.06-1.48) | 1.61 (1.34-1.94) |
   Indian | 766 (7.4) | 64 (6.3) | 0.95 (0.72-1.24) | 1.20 (0.89-1.61) |
   Other | 314 (3.0) | 16 (1.6) | 0.58 (0.35-0.96) | 0.68 (0.40-1.15) |
 Smoking (at booking) |  |  |  |  |
   No | 9086 (87.8) | 908 (89.7) | 1.00 | 1.00 |
   Yes | 778 (7.5) | 69 (6.8) | 0.89 (0.69-1.15) | 0.86 (0.65-1.14) |
   Unknown | 487 (4.7) | 35 (3.5) | 0.72 (0.51-1.02) | 0.67 (0.47-0.97) |
 Maternity care |  |  |  |  |
   Private | 2556 (24.7) | 231 (22.8) | 1.00 | 1.00 |
   Public | 7795 (75.3) | 781 (77.2) | 1.11 (0.95-1.29) | 0.83 (0.69-0.99) |
Pregnancy complications | Â | Â | Â | Â |
 Antepartum haemorrhage‡ |  |  |  |  |
   No | 9899 (95.6) | 924 (91.3) | 1.00 | 1.00 |
   Yes‡ | 378 (3.7) | 60 (5.9) | 1.70 (1.28-2.25) | 1.76 (1.31-2.36) |
   Placenta praevia | 74 (0.7) | 28 (2.8) | 4.06 (2.61-6.30) | 4.00 (2.48-6.47) |
 Diabetes |  |  |  |  |
   Nil | 7651 (73.9) | 733 (72.4) | 1.00 | 1.00 |
   Type 1 or Type 2 | 64 (0.6) | 8 (0.8) | 1.31 (0.62-2.73) | 0.82 (0.38-1.80) |
   Gestational | 463 (4.5) | 52 (5.2) | 1.17 (0.87-1.58) | 0.92 (0.66-1.29) |
   Unknown | 2173 (21.0) | 219 (21.6) | 1.05 (0.90-1.23) | 1.06 (0.90-1.26) |
 Hypertension |  |  |  |  |
   Nil | 9332 (90.2) | 878 (86.8) | 1.00 | 1.00 |
   Chronic | 143 (1.4) | 26 (2.6) | 1.93 (1.27-2.95) | 1.78 (1.13-2.80) |
   Gestational | 523 (5.0) | 56 (5.5) | 1.14 (0.86-1.51) | 0.98 (0.72-1.33) |
   Preeclampsia | 353 (3.4) | 52 (5.1) | 1.57 (1.16-2.11) | 1.33 (0.95-1.85) |
 Induction of labour | 3187 (30.8) | 397 (39.2) | 1.45 (1.27-1.66) | 1.20 (1.03-1.40) |
Delivery outcomes | Â | Â | Â | Â |
 Mode of delivery |  |  |  |  |
   Vaginal |  |  |  |  |
   Spontaneous | 5010 (48.4) | 245 (24.2) | 1.00 | 1.00 |
   Ventouse | 1561 (15.1) | 102 (10.1) | 1.34 (1.05-1.70) | 1.40 (1.09-1.79) |
   Forceps | 711 (6.9) | 70 (6.9) | 2.01 (1.53-2.66) | 1.98 (1.49-2.65) |
   Caesarean |  |  |  |  |
   Prelabour | 1165 (11.2) | 153 (15.1) | 2.69 (2.17-3.32) | 2.99 (2.33-3.83) |
   Emergency in labour | 1904 (18.4) | 442 (43.7) | 4.75 (4.03-5.60) | 4.47 (3.74-5.35) |
 Retained placenta | 109 (1.1) | 38 (3.8) | 3.67 (2.52-5.33) | 6.60 (4.42-9.85) |
Neonatal outcomes | Â | Â | Â | Â |
 Gestation at delivery (days) | 278.7 ± 8.6 | 279.8 ± 8.6 | 1.11 (1.05-1.17) per ↑1wk | 0.96 (0.90-1.03) per ↑1wk |
 Birthweight (g) | 3416 ± 462 | 3621 ± 511 | 1.58 (1.47-1.69) per ↑500g | 1.49 (1.38-1.62) per ↑500g |
 Small for gestational age | 1205 (11.6) | 84 (8.3) | 0.69 (0.55-0.87) | § |
 Large for gestational age | 848 (8.2) | 178 (17.6) | 2.39 (2.01-2.85) | § |