1415-P: Gestational Diabetes Mellitus after Delivery: The Need for Continued Vigilance

Despite guideline recommendations, there are currently limited data on the extent and yield of repeat postpartum glucose testing of women with gestational diabetes mellitus (GDM). Accordingly, we examined these issues in a large population-based cohort of women in Alberta, Canada, who gave birth between 10/01/2008-06/30/2013, were diagnosed with GDM, and followed-up until 12/31/2015 (n=10520). The study population included the 4625 (44%) women who underwent glucose testing within 6 months (m) after delivery. Laboratory data were used to identify rates of repeat testing between 6-18 m postpartum. Diabetes Canada thresholds were used to identify women who converted to diabetes mellitus (DM). A total of 211 (4.6%) women had overt DM, i.e., DM within 6 m of delivery. Among 4414 women with GDM who had a normal glucose test within 6 m, 1656 (37.5%) underwent repeat testing between 6-18 m. Of these, 77 (4.6%) were diagnosed with DM. This latter group was older, more likely multiparous, had higher rates of gestational hypertension and C-section, more likely to have been on insulin therapy during pregnancy, and had the highest rates of large for gestational age (LGA) babies (Table). While early postpartum glucose screening is likely to identify women with overt diabetes, continued monitoring, despite initial normal screens, is necessary to ensure early detection of DM and other chronic disease in women with GDM.