The aim of this study was to evaluate the effects of continuous subcutaneous insulin infusion (CSII) on glycemic control and pregnancy outcomes in Type 1 diabetic pregnant women. We retrospectively evaluated 42 subjects, 20 treated with CSII and 22 with multiple dose insulin injections (MDI). The two groups were comparable for age, pre-pregnancy BMI, and primiparous rate, whereas women in the CSII group showed a tendency toward a longer diabetes duration (p = 0.06). Pre-pregnancy diabetic retinopathy and/or nephropathy were present in nine women of CSII and three of MDI. In all women metabolic control improved during pregnancy, without differences between the two groups and at the end of gestation HbA1c was 6.3 +/- 0.6 in CSII and 6.1 +/- 1.1% in MDI. Moreover, there were no differences in weight gain, whereas insulin requirement resulted significantly (p = 0.009) lower in CSII than in MDI. We recorded only one severe hypoglycaemic episode in both groups. No cases of deteriorations of the chronic diabetic complications were observed. The delivery occurred at 36.4 +/- 2.2 weeks; birth weight, the rate of large for gestational age, and the parameters of foetal morbidity were similar in both groups. In conclusions, CSII and MDI are both effective in improving maternal glucose control and have both similar pregnancy outcomes.