Background: Previous trial-based or modeling studies of cost differences between births following induction of labor (IOL) and expectant management (EM) showed mixed findings and did not account for the full range of costs at a population level.
Methods: We included singleton, cephalic, and term live births between 01/07/2016 and 30/06/2018 in public hospitals of one Australian state (Queensland). We excluded individuals with a previous cesarean birth, no labor, and specific maternal conditions. The mean costs per pregnancy (AUD 2021/22), capturing all health service events and prescription medications accessed during the month of labor and birth, were compared. Generalized linear models were used to calculate cost ratios (CR) and their 95% confidence intervals (CI) after adjusting for potential confounders.
Results: The analysis included 30,924 births. The mean costs per pregnancy (combined women and neonates) were higher for IOL at each week of gestation (37-40), compared with EM, both before and after adjustment, regardless of parity. The largest ($7684, CR = 1.31; 95% CI: 1.23-1.40) and smallest ($1502, CR = 1.06; 95% CI: 1.03-1.09) cost differences were found among nulliparous women at 37 and 39 weeks, respectively. Maternal inpatient admissions largely drove these cost differences.
Discussion: These findings suggest that higher costs associated with IOL in low-risk women are likely due to the intervention itself-such as increased intrapartum procedures or complications-rather than underlying maternal risk. This supports previous evidence of higher cesarean rates after IOL and highlights the need for further evaluation of its cost-effectiveness in the Australian context.