Outpatient Cervical Ripening: A Cost-Minimization and Threshold Analysis

To evaluate cost of outpatient (OP) versus inpatient (IP) ripening with transcervical balloons, and determine circumstances in which each strategy would be cost saving.

We created a decision model comparing OP and IP balloon ripening in term (≥37 weeks) singleton pregnancies with unfavorable cervix. We performed a cost-minimization analysis and threshold analyses comparing two OP ripening strategies (broad and limited use) to IP ripening from a health system perspective. Base case estimates of probability, utilization, and cost were derived from the literature. The primary outcome was incremental cost of OP versus IP ripening from a hospital perspective. One- and two-way sensitivity analyses explored uncertainty in the model.

Both OP ripening strategies were cost saving compared with IP ripening: incremental cost -$228.40/patient with broad use and -$73.48/patient with limited use. OP ripening was no longer cost saving if hours saved on labor and delivery (L&D) were <3.5, insertion visit cost >$714, or facility cost/hour on L&D <$61. Two-way sensitivity analyses showed that OP ripening was cost saving under the most plausible clinical circumstances.

In patients with unfavorable cervix, OP transcervical balloon ripening was cost saving under a wide range of circumstances, particularly if OP ripening can shorten time spent on L&D by 3.5 hours.