[Progression of diabetic retinopathy during pregnancy]

Diabetic retinopathy and pregnancy

Diabetes mellitus and pregnancy have reciprocal influences between them, therefore diabetes mellitus may complicate the course of pregnancy as well as pregnancy can worsen the performance of diabetes especially at the fundus oculi. Several factors seem to play a role in retinal neovascularization. Actually it's not possible to understand the mechanisms underlying this progression. Moreover chronic hyperglycemia leads to several events such as: the activation of aldose reductase metabolic pathway, the activation of the diacylglycerol-protein kinase C, the non-enzymatic glycation of proteins with formation of advanced glycation endproducts and the increase of hexosamines pathway. Although every structure of the eye can be affected by diabetes, retinal tissue, with all its vessels, is particularly susceptible. Pregnancy may promote the onset of diabetic retinopathy, in about 10 % of cases, as well as contribute to its worsening when already present. The proliferative retinopathy must always be treated; treatment should be earlier in pregnant women compared to non-pregnant women. Pregnancy can also cause macular edema; it spontaneously regresses during the postpartum and therefore does not require immediate treatment. In summary, collaboration between the various specialists is primary to ensure the best outcomes for both mother's health and sight, and fetus' health.

Pregnancy-associated retinal diseases and their management

Pregnancy-associated retinal diseases are conditions that may occur uniquely in pregnancy or, more commonly, general conditions that may worsen or alter during pregnancy as a result of hematologic, hormonal, metabolic, cardiovascular, and immunologic changes. Diabetic retinopathy (DR) is by far the most common retinal condition that is altered by pregnancy. However, there are currently no widely accepted, precise clinical guidelines regarding its management during pregnancy. At present it is not possible to predict who will regress and who will progress without treatment. Some of the variation in progression of DR in pregnancy may be a result of well-known risk factors such as hypertension or inadequate glycemic control prior to pregnancy. Other pregnancy-associated retinal diseases are relatively uncommon, and their treatments are poorly characterized. Pre-existing conditions include the white dot syndromes, such as punctuate inner choroidopathy and ocular histoplasmosis syndrome, as well as chorioretinal neovascularization from many other etiologies. Retinal and chorioretinal disorders that can arise during pregnancy include central serous chorioretinopathy and occlusive vasculopathy such as retinal artery occlusion (Purtschers-like retinopathy) and retinal vein occlusion. There remains a small group that appear to be unique to pregnancy, with pre-eclampsia- and eclampsia-associated retinopathy, disseminated intravascular coagulopathy, or amniotic fluid embolism being the best described. In angiogenic retinal diseases outside of pregnancy, the use of anti-vascular endothelial growth factor (anti-VEGF agents) has proven helpful. There are no safety data about the use of anti-VEGF agents during pregnancy, and conventionally the proposed interventions have been laser photocoagulation and systemic or intravitreal injections of steroids. Most of the literature on the treatment of pregnancy associated-chorioretinal neovascularization is anecdotal.