RESUMO
OBJECTIVE: To evaluate the relative cost-effectiveness of starting antenatal fetal surveillance at 32 vs. 36 weeks, in medication-treated gestational diabetes. METHODS: We performed a 2017-2022 retrospective cohort study of patients with medication-treated GDM who underwent BPPs. Patients diagnosed before 24 weeks, those delivered before 32 weeks, and those without BPPs or delivery data were excluded. Demographic and outcome data were abstracted by chart review. We performed a cost-effectiveness analysis regarding two outcomes: stillbirth, and decision to alter delivery timing following abnormal BPPs. RESULTS: A total of 652 pregnancies were included. Patients were 49% privately insured, 25% publicly insured, and 26% uninsured. We assumed that each BPP cost $145. In total, 1,284 BPPs occurred after 36 weeks, costing $186,180, and 2,041 BPPs occurred between 32 and 36 weeks, costing an additional $295,945. Twelve deliveries resulted from abnormal BPPs, all after 36 weeks. No stillbirths occurred. The cost to attempt to avoid one stillbirth was $40,177 across all patients. In our sample, starting surveillance at 36 weeks would have theoretically avoided all stillbirths, with cost savings per avoided stillbirth of $51,572 for privately insured patients, $14,123 for publicly insured patients, and $17,799 for patients without insurance. CONCLUSION: Based on this population with no stillbirths and no BPPs dictating delivery before 36 weeks, surveillance after 36 weeks may be safe and cost-effective. Our findings reflect opportunities for shared decision making and potential practice change, with greatest impact for low socioeconomic status patients and those without insurance.