[Management of diabetic complications during pregnancy using diabetic retinopathy as an example].

Pregnancy may adversely affect the natural course of diabetic retinopathy (DR). Reported rates of new cases or progression of DR during pregnancy range from 10% to 70%. Regression of some of the nonproliferative vascular changes have been reported after delivery. Several risk factors contribute to the aggravation of DR, such as pregnancy itself, duration of the diabetes, elevated glycohemoglobin level, degree of retinopathy at the beginning of the pregnancy, rapid normalization of blood glucose level. The mechanisms by which pregnancy may alter the course of DR is not elucidated: worsening of DR may be due to modifications of retinal blood flow, or to increase in circulating growth factors levels. Careful ophthalmologic monitoring during pregnancy is required. Fundus examination should be performed before pregnancy or at the beginning of it. In patients with no retinopathy, fundus examination should be performed every three months. In those with diabetic retinopathy, fundus examination should be repeated every month. In eyes with proliferative DR or severe nonproliferative DR before pregnancy or at its beginning, laser photocoagulation should be performed promptly.