RESUMO
Objective: To assess the cost-effectiveness of elective induction of labour (IOL) at 41 weeks and expectant management (EM) until 42 weeks. Design: Cost-effectiveness analysis from a healthcare perspective alongside a randomised controlled trial (INDEX). Setting: 123 primary care midwifery practices and 45 obstetric departments of hospitals in the Netherlands. Population: We studied 1801 low-risk women with late-term pregnancy, randomised to IOL at 41 weeks (N = 900) or EM until 42 weeks (N = 901). Methods: The incremental cost-effectiveness ratio (ICER) was expressed as the ratio of the difference in costs and the difference in main perinatal outcomes. A Cost-Effectiveness Acceptability Curve (CEAC) was constructed to assess whether induction is cost-effective for a range of monetary values as thresholds. We performed subgroup analysis for parity. Main outcome measures: Direct medical costs, composite adverse perinatal outcome (CAPO) (perinatal mortality, NICU admission, Apgar 5 min < 7, plexus brachialis injury and/or meconium aspiration syndrome) and composite severe adverse perinatal outcome (SAPO) (including Apgar 5 min < 4 instead of < 7). Results: The average costs were 3858 in the induction group and 3723 in the expectant group (mean difference 135; 95 % CI -235 to 493). The ICERs of IOL compared to EM to prevent one additional CAPO and SAPO was 9436 and 14,994, respectively. The CEAC showed a 80 % chance of IOL being cost-effective with a willingness-to-pay of 22,000 for prevention of one CAPO and 50,000 for one SAPO. Subgroup analysis showed a willingness-to-pay to prevent one CAPO for nulliparous of 47,000 and for multiparous 190,000. To prevent one SAPO the willingness-to-pay is 62,000 for nulliparous and 970,000 for multiparous women. Conclusions: Induction at 41 weeks has an 80 % chance of being cost-effective at a willingness-to-pay of 22,000 for prevention of one CAPO and 50,000 for prevention of one SAPO. Subgroup analysis suggests that induction could be cost-effective for nulliparous women while it is unlikely cost-effective for multiparous women.Cost-effectiveness in other settings will depend on baseline characteristics of the population and health system organisation and funding.
RESUMO
Objective: To assess adverse perinatal outcomes and caesarean section of low-risk women receiving elective induction of labour at 41 weeks or expectant management until 42 weeks according to their preferred and actual management strategy. Design: Multicentre prospective cohort study alongside RCT. Setting: 90 midwifery practices and 12 hospitals in the Netherlands. Population: 3642 low-risk women with uncomplicated singleton late-term pregnancy. Main outcome measures: Composite adverse outcome (perinatal death, Apgar score 5' < 7, NICU admission, meconium aspiration syndrome), composite severe adverse perinatal outcome (all above with Apgar score 5' < 4 instead of < 7) and caesarean section. Results: From 2012-2016, 3642 women out of 6088 eligible women for the INDEX RCT, participated in the cohort study for observational data collection (induction of labour n = 372; expectant management n = 2174; unknown preference/management strategy n = 1096).Adverse perinatal outcome occurred in 1.1 % (4/372) in the induction group versus 1.9 % (42/2174) in the expectant group (adjRR 0.56; 95 %CI: 0.17-1.79), with severe adverse perinatal outcome occurring in 0.3 % (1/372) versus 1.0 % (22/2174), respectively (adjRR 0.39; 95 % CI: 0.05-2.88). There were no stillbirths among all 3642 women; one neonatal death occurred in the unknown preference/management group. Caesarean section rates were 10.5 % (39/372) after induction and 8.9 % (193/2174) after expectant management (adjRR 1.32; 95 % CI: 0.95-1.84).A higher incidence of adverse perinatal outcome was observed in nulliparous compared to multiparous women. Nulliparous 1.8 % (3/170) in the induction group versus 2.6 % (30/1134) in the expectant management group (adjRR 0.58; 95 % CI 0.14-2.41), multiparous 0.5 % (1/201) versus 1.1 % (11/1039) (adjRR 0.54; 95 % CI 0.07-24.19). One maternal death due to amniotic fluid embolism occurred after elective induction at 41 weeks + 6 days. Conclusion: In this cohort study among low-risk women receiving the policy of their preference in late-term pregnancy, a non-significant difference was found between induction of labour at 41 weeks and expectant management until 42 weeks in absolute risks of composite adverse (1.1 % versus 1.9 %) and severe adverse (0.3 % versus 1.0 %) perinatal outcome. The risks in this cohort study were lower than in the trial setting. There were no stillbirths among all 3642 women. Caesarean section rates were comparable.
RESUMO
OBJECTIVE: To compare induction of labour at 41 weeks with expectant management until 42 weeks in low risk women. DESIGN: Open label, randomised controlled non-inferiority trial. SETTING: 123 primary care midwifery practices and 45 hospitals (secondary care) in the Netherlands, 2012-16. PARTICIPANTS: 1801 low risk women with an uncomplicated singleton pregnancy: randomised to induction (n=900) or to expectant management until 42 weeks (n=901). INTERVENTIONS: Induction at 41 weeks or expectant management until 42 weeks with induction if necessary. PRIMARY OUTCOME MEASURES: Primary outcome was a composite of perinatal mortality and neonatal morbidity (Apgar score <7 at five minutes, arterial pH <7.05, meconium aspiration syndrome, plexus brachialis injury, intracranial haemorrhage, and admission to a neonatal intensive care unit (NICU). Secondary outcomes included maternal outcomes and mode of delivery. The null hypothesis that expectant management is inferior to induction was tested with a non-inferiority margin of 2%. RESULTS: Median gestational age at delivery was 41 weeks+0 days (interquartile range 41 weeks+0 days-41 weeks+1 day) for the induction group and 41 weeks+2 days (41 weeks+0 days-41 weeks+5 days) for the expectant management group. The primary outcome was analysed for both the intention-to-treat population and the per protocol population. In the induction group, 15/900 (1.7%) women had an adverse perinatal outcome versus 28/901 (3.1%) in the expectant management group (absolute risk difference -1.4%, 95% confidence interval -2.9% to 0.0%, P=0.22 for non-inferiority). 11 (1.2%) infants in the induction group and 23 (2.6%) in the expectant management group had an Apgar score <7 at five minutes (relative risk (RR) 0.48, 95% CI 0.23 to 0.98). No infants in the induction group and three (0.3%) in the expectant management group had an Apgar score <4 at five minutes. One fetal death (0.1%) occurred in the induction group and two (0.2%) in the expectant management group. No neonatal deaths occurred. 3 (0.3%) neonates in the induction group versus 8 (0.9%) in the expectant management group were admitted to an NICU (RR 0.38, 95% CI 0.10 to 1.41). No significant difference was found in composite adverse maternal outcomes (induction n=122 (13.6%) v expectant management n=102 (11.3%)) or in caesarean section rate (both groups n=97 (10.8%)). CONCLUSIONS: This study could not show non-inferiority of expectant management compared with induction of labour in women with uncomplicated pregnancies at 41 weeks; instead a significant difference of 1.4% was found for risk of adverse perinatal outcomes in favour of induction, although the chances of a good perinatal outcome were high with both strategies and the incidence of perinatal mortality, Apgar score <4 at five minutes, and NICU admission low. TRIAL REGISTRATION: Netherlands Trial Register NTR3431.