Cost-effectiveness analysis of induction of labour at 41 weeks and expectant management until 42 weeks in low risk women (INDEX trial)

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 com-posite severe adverse perinatal outcome (SAPO) (including Apgar 5 min < 4 instead of < 7).Results: The average costs were euro3858 in the induction group and euro3723 in the expectant group (mean difference euro135; 95 % CI-235 to 493). The ICERs of IOL compared to EM to prevent one additional CAPO and SAPO was euro9436 and euro14,994, respectively. The CEAC showed a 80 % chance of IOL being cost-effective with a willingness-to-pay of euro22,000 for prevention of one CAPO and euro50,000 for one SAPO. Subgroup analysis showed a willingness-to-pay to prevent one CAPO for nulliparous of euro47,000 and for multiparous euro190,000. To prevent one SAPO the willingness-to-pay is euro62,000 for nulliparous and euro970,000 for multiparous women. Conclusions: Induction at 41 weeks has an 80 % chance of being cost-effective at a willingness-to-pay of euro22,000 for prevention of one CAPO and euro50,000 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.

Automated summary

This study assessed the cost-effectiveness of elective induction of labour (IOL) at 41 weeks compared to expectant management (EM) until 42 weeks for late-term pregnancies. The results showed that IOL has an 80% chance of being cost-effective for preventing adverse perinatal outcomes at a certain willingness-to-pay threshold. Subgroup analysis suggested that IOL may be cost-effective for nulliparous women, but unlikely to be cost-effective for multiparous women. The cost-effectiveness in other settings will depend on the baseline characteristics of the population and the organization and funding of the healthcare system.