Sociodemographic barriers to continuous glucose monitoring among pregnancies with type 1 diabetes.

Objective: Continuous glucose monitor (CGM) use is associated with improved glycemic management among pregnant patients with type 1 diabetes. Individual- and neighborhood-level social determinants of health (SDHs) are associated with low CGM use and adverse pregnancy outcomes. We hypothesized that SDHs are associated with decreased CGM use in pregnancy among patients with type 1 diabetes. Methods: We evaluated a cohort of pregnancies receiving type 1 diabetes and delivery care at a single large health system from 2016 to 2023. Patients were evaluated by public payor status. The primary outcome was CGM use. Additional SDH characteristics evaluated included home Area Deprivation Index (ADI) percentile and rurality status. Regression analyses generating models predicting CGM use included age, baseline body mass index (BMI), diabetes duration, and delivery year. Results: Among 288 pregnancies with type 1 diabetes, 144 (50.0%) had public insurance. Public payor was associated with younger age and shorter diabetes duration, and those patients were more commonly nulliparous and Black. Controlling for baseline characteristics, CGM uptake was lower among the public insured (38.9% vs. 61.8%; adjusted odds ratio [aOR], 0.39; 95% confidence interval [CI], 0.23-0.66). Over time, uptake increased, though publicly insured patients lagged by two years. Evaluating SDH characteristics and CGM usage over time, public insurance (aOR, 0.47; 95% CI, 0.24-0.91) and ADI (aOR, 0.96; 95% CI, 0.95-0.98) were associated with CGM use; rurality was not. Conclusion: Public insurance and high neighborhood deprivation are risk factors for lower CGM uptake, potentially representing an indirect and targetable mechanism by which SDH impacts glycemic management for pregnancies with type 1 diabetes.