Table 4.
Intrapartum risk factors for neonatal encephalopathy. Values are numbers (percentages) unless stated otherwise
| Risk factor | Encephalopathic infants | Controls | Unadjusted odds ratio | Adjusted odds ratio* (95% CI) |
|---|---|---|---|---|
| Presentation | n=131 | n=635 | ||
| Cephalic | 119 (91) | 611 (96.2) | 1 | 1 |
| Non-cephalic | 12 (9) | 24 (3.8) | 2.57 | 3.35 (1.38 to 8.11) |
| Prolonged rupture of membranes (>24 hours) | n=122 | n=624 | ||
| No | 109 (89) | 597 (95.7) | 1 | 1 |
| Yes | 13 (11) | 27 (4.3) | 2.64 | 3.84 (1.56 to 9.47) |
| Onset of labour | n=130 | n=620 | ||
| Spontaneous | 118 (91) | 591 (95.3) | 1 | 1 |
| Induced | 12 (9) | 29 (4.7) | 2.07 | 5.28 (2.03 to 13.76) |
| Mode of delivery | n=130 | n=631 | ||
| Elective caesarean section | 0 (0) | 16 (2.5) | † | † |
| Unassisted vaginal | 85 (65) | 553 (87.6) | 1 | 1 |
| Vacuum | 17 (13) | 16 (2.5) | 6.91 | 7.93 (3.02 to 20.78) |
| Forceps | 5 (4) | 4 (0.6) | 8.13 | 6.11 (1.005 to 37.17) |
| Emergency caesarean section | 23 (18) | 42 (6.7) | 3.56 | 3.91 (1.96 to 7.84) |
| Intrapartum complications | n=131 | n=634 | ||
| None | 103 (79) | 617 (97.3) | 1 | 1 |
| Clinically obstructed labour | 19 (15) | 16 (2.5) | 7.11 | 5.73 (2.30 to 14.23) |
| Other | 9 (7)‡ | 1 (0.2)§ | 53.9 | 28.16 (2.88 to 275.6) |
| Meconium | n=127 | n=607 | ||
| None | 66 (52) | 573 (94.4) | 1 | 1 |
| Thin | 20 (16) | 21 (3.5) | 8.27 | 6.04 (2.56 to 14.25) |
| Thick | 41 (32) | 13 (2.1) | 27.38 | 18.21 (8.05 to 41.18) |
| Syntocinon | n=130 | n=620 | ||
| None | 68 (52) | 452 (72.9) | 1 | 1 |
| Induction | 12 (9) | 29 (4.7) | 2.75 | 9.09 (3.32 to 24.83) |
| Augmentation | 50 (39) | 139 (22.4) | 2.39 | 3.51 (2.04 to 6.07) |
| Duration of labour (hours) | n=123 | n=598 | ||
| <24 primiparous or <12 multiparous | 87 (71) | 429 (71.7) | 1 | 1 |
| >24 primiparous or >12 multiparous | 36 (29) | 169 (28.3) | 1.05 | 1.04 (0.60 to 1.80) |
| Admission to delivery (hours) | n=130 | n=622 | ||
| <1 | 19 (15) | 99 (15.9) | 1 | 1 |
| 1-4 | 34 (26) | 153 (24.6) | 1.15 | 1.23 (0.57 to 2.65) |
| 5-12 | 40 (31) | 208 (33.4) | 1.00 | 1.23 (0.57 to 2.64) |
| 12-24 | 22 (17) | 91 (14.6) | 1.25 | 1.96 (0.85 to 4.50) |
| >24 | 15 (12) | 71 (11.4) | 1.10 | 1.58 (0.60 to 4.14) |
*
Adjusted for maternal age, parity, education, height, previous neonatal death, antenatal care, pre-eclampsia, birth weight, sex of infant, and plurality.
†
Omitted from odds ratio estimation owing to zero prevalence in cases.
‡
Cord prolapse (four), maternal convulsion (two), haemorrhage (two), uterine rupture (one).
§
Maternal convulsion (one).