AIM:To study the association of serum insulin-like growth factor-1(IGF-1)with diabetic retinopathy.METHODS:Serum IGF-1 levels were measured in 25 pregnant diabetic patients and 25 pregnant non-diabetic patients who were matched for age,ethnicity,parity and period of gestation.Fundus examination was performed in both groups at 28,32 and 36 weeks of gestation.RESULTS:The serum IGF-1 level was significantly elevated in pregnant diabetics compared to pregnant non-diabetics [366±199μg/L vs 184±89μg/L(P=0.0001)at 24 weeks,535±251μg/L vs 356±89μg/L(P=0.007)at 32 weeks and 404±166μg/L vs 264±113μg/L(P=0.003)at 36 weeks of gestation].The pregnant diabetics with established diabetes had significantly higher IGF-1 level than gestational diabetes at 28,32 and 36 weeks of gestation.The serum IGF-1 level in pregnant diabetics with retinopathy was significantly higher than in those without retinopathy at all periods of gestation.CONCLUSION:Increased serum IGF-1 in pregnancy may increase the risks for retinopathy.