Progression of diabetic retinopathy during pregnancy in women with type 2 diabetes

We studied the progression of diabetic retinopathy during pregnancy in women with type 2 diabetes.

Fundus photography was performed at median 10 (range 6-21) and 28 (27-37) gestational weeks in 80 of 110 (73%) consecutively referred pregnant women with type 2 diabetes. Diabetic retinopathy was classified in five stages. Progression was defined as at least one stage of deterioration of diabetic retinopathy and/or development of macular oedema on at least one eye between the two examinations. Macular oedema was defined as retinal thickening and/or hard exudates within a diameter of 1,500 microm in the macula area.

Diabetic retinopathy, mainly mild, was present in 11 (14%) women in early pregnancy. Median duration of diabetes was 3 years (range 0-16 years). At baseline, HbA(1c) was 6.4% (1.0) (mean [SD]), systolic BP 121 (13) and diastolic BP 72 (9) mmHg. Prior to pregnancy, 22 (28%) women had been on insulin treatment. During pregnancy 74 women (93%) were treated with insulin and 11 (14%) with antihypertensive medication. Progression of diabetic retinopathy was observed in 11 (14%) women. Progression was mainly mild, but one woman with poor glycaemic control and uncontrolled hypertension progressed from mild retinopathy to sight-threatening retinopathy with proliferations, clinically significant macular oedema and impaired vision in both eyes. Progression of diabetic retinopathy was associated with a longer duration of diabetes (p = 0.03) and insulin treatment before pregnancy (p = 0.004).

Despite a low risk of progression of retinopathy in pregnant women with type 2 diabetes, sight-threatening deterioration did occur.