Gestational diabetes in Korea: temporal trends in prevalence, treatment, and short-term consequences from a national health insurance claims database between 2012 and 2016 Running head: Gestational diabetes mellitus in Korea 2012–2016

Abstract Aims This population-based cross-sectional study aimed to investigate recent trends in the prevalence and treatment of gestational diabetes mellitus (GDM) in Korea. We also investigated trends in annual prevalence rate of pregnancy-induced hypertension (PIH) and cesarean section (C-section) in GDM patients. Methods We used data from the Health Insurance Review and Assessment-National Patient Sample (HIRA-NPS) database, 2012–2016. Non-GDM (n=53,698) and GDM (n=7,956) patient data were analyzed for each year. Results The annual increase in the prevalence of GDM was 11.1% over 2012–2016, with a significant continuously increasing trend (p Conclusions The prevalence of GDM in Korean women and C-section rates in women with GDM showed a significantly increasing trend, 2012–2016. There is a need for further efforts to monitor this trend and to identify associated risk factors for GDM in Korean women.