Insulinomas are rare neuroendocrine tumors with an incidence of 4 per 1,000,000 person-years, being even rarer during pregnancy. During pregnancy most cases are recognized or become symptomatic during the first trimester. A 29-year-old woman, primigravida, was hospitalized in the 38th gestational week due to slurred speech, weakness and slow reaction patterns. An electroencephalogram and computed tomography scan of the brain and blood samples were normal. Blood pressure was 170-145/110-95 mmHg, albuminuria was moderate and there was moderate edema of the ankles. Labor started spontaneously the third day, 62 h after of hospitalization, and the patient gave birth to a healthy girl with no neonatal problems. Fourteen hours after delivery, the patient became comatose and developed universal clonic seizures. At the same time plasma glucose was