Prevalence and severity of diabetic retinopathy in pregnant women with diabetes-time to individualize photo screening frequency.

Aims: To evaluate the prevalence and severity of diabetic retinopathy including macular oedema in pregnant women with diabetes and to identify women in whom the frequency of retinal screening can be reduced to minimize the burden of health care visits.

Methods: A cohort study of 348 women with pre-existing diabetes were routinely screened with retinal photo in early (12 weeks) and late pregnancy (27 weeks). Diabetic retinopathy was classified in five stages in accordance with National Danish Guidelines based on the eye with the highest retinopathy level. Sight-threatening retinopathy was defined as the presence of proliferative retinopathy and/or clinically significant macular oedema (CSMO).

Results: Retinopathy was present in 52% (116/223) vs. 14% (17/125), with sight-threatening retinopathy in 16% (35/223) vs. 6% (7/125) of women with type 1 and type 2, respectively. Women without retinopathy in early and late pregnancy were characterized by shorter diabetes duration (p < 0.0001 and p = 0.008) and predominance of type 2 diabetes. Amongst the 50% (175/348) of the cohort having no retinopathy in early pregnancy and HbA1c<53 mmol/mol (7.0%), none developed sight-threatening retinopathy and 94% (165/175) remained without any retinopathy during pregnancy. Development of sight-threatening retinopathy was mainly observed in women with retinopathy in early pregnancy. Treatment for sight-threatening retinopathy was given to a minority (2.7 and 2.4%, respectively).

Conclusion: Good glycaemic control and no retinopathy was seen in a large proportion of women in early pregnancy and none of these women developed sight-threatening retinopathy. The frequency of retinal screening can probably be safely reduced during pregnancy in these women.