Table 6. Maternal outcomes in the population included in the IPD-MA.
| Variable | IOL group (n = 2,281) | EM group (n = 2,280) |
RR (95% CI) | p-value | RD per 10,000 (95% CI) |
Heterogeneity | |
|---|---|---|---|---|---|---|---|
| I2 (%) | p-value | ||||||
| Pain treatment (Use of epidural/spinal/opiates)* |
1,153 (50.5) | 1,058 (46.4) | 1.09 (1.03; 1.16) | 0.005 | 414 (125; 703) | 0 | 0.85 |
| Use of epidural anaesthesia | 998 (43.8) | 906 (39.7) | 1.10 (1.03; 1.17) | 0.006 | 400 (122; 678) | 0 | 0.50 |
| Use of opiates | 184 (8.1) | 173 (7.6) | NE | NE | NE | NE | NE |
| Fever during labour | 177 (7.8) | 151 (6.6) | 1.17 (0.95; 1.44) | 0.14 | 114 (−96; 195) | 0 | 0.66 |
| Antibiotics during labour | 296 (13.0) | 297 (13.0) | 0.99 (0.85; 1.15) | 0.88 | −6 (−197; 185) | 62 | 0.11 |
| Therapy | 128 (5.6) | 104 (4.6) | 1.23 (0.96; 1.58) | 0.11 | 105 (−22; 232) | 0 | 0.62 |
| Prophylaxis | 168 (7.4) | 193 (8.5) | 0.87 (0.71; 1.05) | 0.15 | −111 (−264; 43) | 30 | 0.23 |
| Episiotomy‡ | 328 (14.4) | 335 (14.7) | 0.97 (0.85; 1.11) | 0.71 | −30 (−226; 166) | 0 | 0.53 |
| Perineal lacerations III and IV§ | 68 (3.0) | 81 (3.6) | 0.84 (0.61; 1.15) | 0.28 | −57 (−160; 46) | 0 | 0.71 |
| Postpartum haemorrhage (>1,000 ml)¶ | 208 (9.1) | 204 (9.0) | 0.98 (0.82; 1.17) | 0.86 | 17 (−149; 184) | 70 | 0.067 |
| Postpartum haemorrhage (>2,000 ml)¶ | 42 (1.8) | 34 (1.5) | 1.23 (0.79; 1.93) | 0.36 | 35 (−39; 109) | 0 | 0.56 |
| Retained placenta (all) | 93 (4.1) | 90 (3.9) | 1.03 (0.78; 1.37) | 0.82 | 13 (−101; 127) | 10 | 0.29 |
| Retained placenta with haemorrhage (>1,000 ml) |
62 (2.7) | 61 (2.7) | 1.02 (0.72; 1.44) | 0.93 | 4 (−90; 98) | 0 | 0.91 |
| Retained placenta with haemorrhage (≤1,000 ml) |
31 (1.4) | 29 (1.3) | 1.07 (0.65; 1.77) | 0.80 | 9 (−57; 75) | 63 | 0.10 |
| Hypertensive disorders| | 26 (1.1) | 66 (2.9) | 0.39 (0.25; 0.61) | <0.001 | −176 (−257; −94) | 0 | 0.39 |
| Maternal venous thromboembolism | 0 (0.0) | 1 (0.0) | NE | NE | NE | NE | NE |
| Maternal admission to intensive care unit | 5 (0.2) | 2 (0.1) | 2.50 (0.49; 12.86) | 0.27 | 13 (−10; 36) | 0 | NE |
| Maternal death | 0 (0.0) | 0 (0.0) | NE | NE | NE | NE | NE |
Values are numbers (percentages) unless stated otherwise. RR is adjusted for RCT.
* In the INDEX trial, a combination of epidural and opiates was possible.
‡ With and without perineal lacerations III and IV.
§ With and without episiotomy.
¶ Based on measured blood loss and not ICD-10 codes reported.
| Hypertensive disorders of pregnancy including eclampsia and HELLP.
CI, confidence interval; EM, expectant management; HELLP, haemolysis, elevated liver enzymes, and a low platelet count; ICD-10, International Classification of Diseases 10th Revision; INDEX, INDuction of labour at 41 weeks versus a policy of EXpectant management until 42 weeks; IOL, induction of labour; IPD-MA, individual participant data meta-analysis; NE, not estimated due to 0 events in both arms in 1 or both trials; RD, risk difference; RCT, randomised controlled trial; RR, relative risk.