A history of gestational diabetes mellitus (GDM) may have long-term implications for microvascular complications in women who later develop diabetes. A nationwide, register-based cohort study published in Diabetes Care evaluated whether prior GDM is associated with an increased risk of diabetic retinopathy (DR), with additional assessment of GDM severity and postpregnancy hypertension.

The study included 708,250 women who gave birth in Denmark between 1997 and 2018, with a median follow-up of 12 years. GDM and DR were identified using International Classification of Diseases, Tenth Revision (ICD-10) codes. GDM severity was assessed based on insulin treatment during pregnancy, while subsequent diabetes and hypertension were defined using diagnostic codes and medication data. Cox regression models were used to estimate risk.

Among women who developed diabetes (n=18,556), DR occurred in 655 individuals. Prior GDM was associated with a higher risk of DR (adjusted hazard ratio [aHR] 3.0; 95% confidence interval [CI], 2.6-3.6). The risk increased with greater GDM severity, with higher estimates in insulin-treated cases (aHR 5.6) compared with non-insulin-treated cases (aHR 2.4). In women with subsequent hypertension, prior GDM was associated with a higher DR risk (aHR 2.7; 95% CI, 2.1-3.5).

These findings indicate that GDM history is associated with increased DR risk in women with diabetes, supporting its consideration in long-term screening strategies.