Table 3.
Perinatal outcome in intention to treat groups. Values are numbers (percentages) unless stated otherwise
| Variables | Induction group (n=1381) | Expectant management group (n=1379) | Relative risk (95% CI) | P value; mean (95% CI) difference between groups |
|---|---|---|---|---|
| Primary composite outcome | ||||
| Primary composite outcome | 33/1381 (2.4) | 31/1379 (2.2) | 1.06 (0.65 to 1.73) | 0.90 |
| Subcomponents of primary composite outcome | ||||
| Perinatal/neonatal mortality (stillbirth+neonatal mortality) | 0/1381 (0.0) | 6/1379 (0.4) | — | 0.03 |
| Stillbirth | 0/1381 (0.0) | 5/1379 (0.4) | — | 0.06 |
| Neonatal mortality (live births with death days 0-27) | 0/1381 (0.0) | 1/1374 (0.1) | — | 1.00 |
| Neonatal morbidity | 33/1381 (2.4) | 26/1374 (1.9) | 1.27 (0.76 to 2.11) | 0.43 |
| Subcomponents of neonatal morbidity | ||||
| Apgar score <7 at 5 minutes* | 18/1381 (1.3) | 16/1374 (1.2) | 1.12 (0.57 to 2.19) | 0.88 |
| Metabolic acidosis† | 14/661 (2.1) | 10/644 (1.6) | 1.36 (0.61 to 3.05) | 0.58 |
| Hypoxic ischaemic encephalopathy grades 1-3 | 2/1381 (0.1) | 3/1374 (0.2) | 0.66 (0.11 to 3.96) | 1.00 |
| Intracranial haemorrhage | 1/1381 (0.1) | 2/1374 (0.1) | 0.50 (0.05 to 5.48) | 1.00 |
| Neonatal convulsions | 1/1381 (0.1) | 3/1374 (0.2) | 0.33 (0.03 to 3.18) | 0.62 |
| Meconium aspiration syndrome | 2/1381 (0.1) | 3/1374 (0.2) | 0.66 (0.11 to 3.96) | 1.00 |
| Mechanical ventilation within first 72 hours | 3/1381 (0.2) | 5/1374 (0.4) | 0.60 (0.14 to 2.49) | 0.72 |
| Obstetric brachial plexus injury | 4/1381 (0.3) | 1/1374 (0.1) | 3.98 (0.45 to 35.56) | 0.38 |
| Additional secondary neonatal outcome variables | ||||
| Admittance to NICU | 55/1381 (4.0) | 82/1374 (6.0) | 0.67 (0.48 to 0.93) | 0.02 |
| Apgar score <4 at 5 minutes* | 3/1381 (0.2) | 1/1374 (0.1) | 2.98 (0.31 to 28.66) | 0.63 |
| Therapeutic hypothermia | 1/1381 (0.1) | 2/1374 (0.1) | 0.50 (0.05 to 5.48) | 1.00 |
| Macrosomia (≥4500 g) | 68/1381 (4.9) | 114/1379 (8.3) | 0.60 (0.45 to 0.80) | <0.001 |
| Birth weight (g): | n=1381 | n=1379 | ||
| Mean (SD) | 3815 (409) | 3875 (436) | — | <0.001; −60.1 (−91.8 to −29.6) |
| Median (interquartile range) | 3804 (3536-4090) | 3865 (3570-4160) | — | — |
| Jaundice requiring phototherapy or exchange transfusion | 16/1381 (1.2) | 32/1374 (2.3) | 0.50 (0.27 to 0.90) | 0.03 |
| Pneumonia | 8/1381 (0.6) | 13/1374 (0.9) | 0.61 (0.25 to 1.47) | 0.38 |
| Sepsis | 9/1381 (0.7) | 20/1374 (1.5) | 0.45 (0.20 to 0.98) | 0.06 |
| Exploratory neonatal outcome variables | ||||
| Days in NICU: | n=55 | n=81‡ | ||
| Mean (SD) | 3.38 (2.97) | 4.59 (5.64) | — | 0.15; −1.21 (−2.78 to 0.20) |
| Median (interquartile range) | 2 (1-6) | 3 (1-6) | — | — |
| Admittance to NICU >4 days | 34/55 (61.8) | 45/81 (55.6) | 1.11 (0.84 to 1.48) | 0.58 |
| Hypoglycaemia§ | 22/1381 (1.6) | 20/1374 (1.5) | 1.09 (0.60 to 2.00) | 0.89 |
| Birth trauma¶ | 0/1381 (0.0) | 1/1374 (0.1) | 1.00 | |
| Small for gestational age** | 9/1381 (0.7) | 22/1379 (1.6) | 0.41 (0.19 to 0.88) | 0.03 |
| Large for gestational age** | 21/1381 (1.5) | 26/1379 (1.9) | 0.81 (0.46 to 1.43) | 0.55 |
| Any major birth defect†† | 14/1381 (1.0) | 17/1379 (1.2) | 0.82 (0.41 to 1.66) | 0.72 |
| Girl | 600/1381 (43.4) | 623/1379 (45.2) | 0.96 (0.88 to 1.05) | 0.38 |
NICU=neonatal intensive care unit.
Apgar score of live births.
Denominator based on validated umbilical cord blood samples at birth. Validated samples defined as arterial pH less than venous pH and arterial partial pressure of carbon dioxide (pCO2) greater than venous pCO2.
One infant with only home based neonatal care.
Hypoglycaemia defined as P-glucose concentration <2.6 mmol/L after three hours.
Any of long bone fracture, clavicular fracture, skull fracture, other neurological injury, retinal haemorrhage, and facial nerve palsy.
Small for gestational age defined as ≤2 standard deviations and large for gestational age as ≥2 standard deviations, according to Swedish sex specific reference.17
Minor birth defects according to EUROCAT (European Concerted Action on Congenital Anomalies and Twins) definition excluded.21