Managing diabetic patients with nephropathy and other vascular complications

Since the metabolic changes in normal pregnancy are diabetogenic, pregnancy imposes a severe stress on the metabolic milieu of diabetic patients. Moreover, many patients with long-standing diabetes have vascular complications, including retinopathy, renal insufficiency, nephrotic syndrome and hypertension, that represent separate risk factors for optimal fetal development. Recent experience has suggested that maternal hyperglycaemia, and associated fetal hyperinsulinaemia, may represent an important factor in the development of fetal complications. During the past two to three decades the incidence of perinatal deaths has been reduced in all cases of diabetics to a level that approaches the rate in healthy gravidas when severe congenital anomalies are excluded. Fetal and neonatal morbidity have also been reduced, although rates of congenital anomalies, polyhydramnios and respiratory distress syndrome remain high. In patients with significant vascular complications, especially nephropathy and retinopathy, there is no evidence that pregnancy alters the natural course of these complications. Although the morbidity associated with oedema formation and hypertension is elevated, with meticulous management of patients with diabetic nephropathy, especially in the absence of severe renal insufficiency and/or severe hypertension, pregnancy performance and outcome can be similar to other insulin-dependent diabetics.