The obstetrical management of pregnant women with pregestational diabetes has been significantly improved throughout recent years. In the past, efforts to maintain euglycaemia during pregnancy in the presence of a labile maternal metabolism led to repeated, long-term hospitalization. In an interdisciplinary joint effort a protocol was delineated to obtain euglycemia throughout pregnancy by functional insulin therapy aiming at "near-normoglycemic insulin substitution (NIS)". In order to achieve this goal, home glucose monitoring and, depending on the glucose levels, self-made adjustments to the insulin therapy (according to individual algorithm) are the essential parts of this protocol. Of our study group of 18 pregnant diabetic women, already eight of them (2 class B, 1 class C, 1 class D, 2 class R and 2 class RF) have been delivered. The mean maternal age was 27 years (21-39). All metabolic variables of consequence for a diabetic woman were within the normal limits. The mothers' mean weight gain was 16 kg (12-20), and the mean gestational age at delivery was 37.8 weeks (35-40). The mean birth weight was 3293 grams (2700-3700) and all newborns were within the 50th percentile. Five fetuses were delivered by caesarian section (indications: proliferative retinopathy 3, breech presentation 1, previous caesarian section 1). No congenital malformations were found, nor macrosomia, respiratory distress syndrome or postpartum hyperglycaemia in the newborn. These preliminary results are encouraging. We feel that functional insulin therapy aiming at "near-normoglycaemic insulin substitution" promises to be very effective for women who are able and willing to follow the instructions received in the special education program.