BACKGROUND: Patients with gestational diabetes mellitus (GDM) have a 40-70% lifetime risk for developing type 2 diabetes mellitus, which is 9 times the risk of patients without a history of GDM. Joint association guidelines recommend a 75-gram, 2-hour oral glucose tolerance test (GTT) at 4 to 12 weeks postpartum for all patients with GDM, and to follow-up with a primary care physician. Currently, less than half of these patients do not receive the recommended postpartum glucose testing and/or follow-up. METHODS: For each GDM-affected pregnancy, two primary outcome measures were retrospectively collected from the clinic EHR: completion of the 75-gram GTT at 4-12 weeks postpartum and referral to a PCP. The respective variables were marked as completed or not completed and data was allocated to the month in which the patient delivered. RESULTS: From July 2022 to February 2024, 11.8 % (n=46) of the clinic’s patients (N=391) were diagnosed with GDM using the two-step regimen and followed postpartum to collect outcome measure data. Cumulative postpartum compliance rates for patients with GDM were 28% for completion of the 75-gram GTT and 11% for receipt of referral to PCP. Monthly compliance rates varied largely. CONCLUSION: Low postpartum follow-up compliance rates highlight the proposed quality gap for patients whose pregnancies were affected by GDM. Future research should identify specific compliance barriers and investigate their impact upon postpartum follow-up, and ultimately improve compliance rates with deliberate and incremental positive change(s) to the current framework for postpartum and longitudinal care of patients with GDM.