(215) Delayed gestational diabetes diagnosis: maternal characteristics, reasons for delay, and delivery outcomes

To assess maternal characteristics, reasons for delay, and delivery outcomes among patients with delayed gestational diabetes (GDM) diagnoses compared to those with timely diagnoses.

Study Design:

This is a retrospective cohort study of pregnant patients who delivered at a single tertiary hospital from 2013-2021. Patients with pre-gestational diabetes, early diagnosis of GDM ( < 24 weeks), and multifetal gestations were excluded. “Timely” diagnosis was defined as a GCT >200mg/dL or GTT with >2 abnormal values between 24⁰-32⁰ weeks, whereas “delayed” diagnosis included patients diagnosed >32⁰. Maternal characteristics and delivery outcomes were compared between groups among the entire cohort, whereas neonatal outcomes were compared between groups among deliveries >35 weeks, given routine NICU admission for all deliveries < 35 weeks. Bivariate analyses were performed. Reasons for delayed diagnosis were elucidated by chart review of 50 randomly selected charts. 

Results:

Of 2222 eligible patients with GDM, 1970 (88.7%) had timely diagnoses and 252 (11.3%) had delayed diagnoses. Patients with delayed diagnoses were younger, more likely to be multiparous, Hispanic or Black, non-English speaking, single, smokers, have public insurance, and entered later into prenatal care. They were also more likely to exceed IOM gestational weight gain guidelines (Table 1). Patients with delayed diagnoses were less likely to be started on insulin as compared to patients with timely diagnoses (10.3% vs 25.6%, p= < 0.01). Delivery and neonatal outcomes were not significantly different between groups (Table 2). Delayed diagnoses were most often due to patient delays in undergoing recommended testing (62%) and systems delays such as late transfer of care or lab error (14%).

Conclusion:

Despite a “higher-risk” profile of patients receiving delayed GDM diagnoses, delivery and neonatal outcomes were similar between groups. In a sample of 50 cases, most delays were patient-driven. This study highlights important disparities in GDM diagnosis and identifies patients who may benefit from targeted interventions to promote timely testing.