Cost-effectiveness of induction of labour versus serial antenatal monitoring in the Canadian Multicentre Postterm Pregnancy Trial

Abstract

Objective: To determine the cost-effectiveness of induction of labour versus serial fetal monitoring while awaiting spontaneous labour in postterm pregnancies.

Design: Cost-effectiveness and cost-minimization analyses conducted as part of a Canadian multicentre randomized clinical trial.

Setting: Twenty-two Canadian hospitals, of which 19 were teaching hospitals and 3 were community hospitals.

Patients: Women with uncomplicated pregnancies of 41 or more weeks' gestation were randomly assigned to induction of labour or serial antenatal monitoring. Of the 3418 women enrolled, no data were received on 11. Therefore, results were based on data from 1701 women in the induction arm of the study and 1706 women in the monitoring arm.

Main outcome measures: Perinatal mortality and neonatal morbidity, rates of cesarean section and health care costs. Hospital costing models were developed specifically for the study. Data on use of major resources (e.g., length of hospital stay, surgical procedures, major diagnostic tests and procedures, and medications) for all trial participants were collected and combined with data on minor tests and procedures (e.g., laboratory tests) abstracted from a detailed review of medical records of a sample of patients.

Results: Because the results of the clinical trial showed a nonsignificant difference in perinatal mortality and neonatal morbidity between the induction and monitoring arms, the authors conducted a cost-minimization rather than a cost-effectiveness analysis. The mean cost per patient with a postterm pregnancy managed through monitoring was $3132 (95% confidence interval [CI] $3090 to $3174) and per patient who underwent induction of labour was $2939 (95% CI $2898 to $2981), for a difference of $193. The significantly higher (p < 0.0001) mean cost per patient in the monitoring arm was due mainly to the costs of additional monitoring and the significantly higher rates of cesarean section among these patients. Estimated conservatively, the savings resulting from a universal policy of managing postterm pregnancies by induction of labour in Canada may be as high as $8 million a year.

Conclusions: A policy of managing postterm pregnancy through induction of labour not only results in more favourable outcomes than a monitoring strategy but does so at a lower cost.