Impact of pregnancy on the progression of diabetic retinopathy in Type 1 diabetes

Aims: To evaluate the impact of pregnancy on the progression of diabetic retinopathy in women with Type 1 diabetes mellitus and to identify risk factors for the progression of retinopathy during pregnancy. Methods: One hundred and seventy-nine pregnancies in 139 women with pregestational Type 1 diabetes were studied prospectively between January 1990 and December 1998. Dilated fundal examination was performed at booking, 24 weeks and 34 weeks or 4–6 weekly if retinopathy present at booking. Data were collected on glycaemic control (HbA1c) throughout pregnancy. Results: Progression to proliferative retinopathy was seen in four (2.2%) pregnancies while moderate progression was seen in a further five (2.8%) pregnancies. Progression of retinopathy was significantly increased in women with duration of diabetes 10–19 years compared with duration 10 years and in women with moderate to severe retinopathy at baseline. Laser therapy was needed in 2.2% pregnancies, which is much lower than that reported in earlier studies