Diabetes mellitus is a growing worldwide issue, and in pregnancy implies an increased maternal and fetal risk, especially in instances of poorly regulated maternal hyperglycaemia. Diabetes in pregnancy is understood as either pregestational diabetes (type 1, 2 i and others, less frequent varieties) and gestational diabetes mellitus (GDM). Depending on the timing of maternal hypergycaemia, it may affect fertility, miscarriage and malformation rate (diabetic embryopathy), as well as cause so-called diabetic fetopathy by way of fetal hyperglycaemia and hyperinsulinaemia (macrosomia, hypoglycaemia, jaundice, a higher incidence of neonatal respiratory distress syndrome et cetera). In addition, diabetes mellitus has an effect on prematurity rate and the occurence of abnormal fetal presentation and position, shoulder dystocia and perinatal asphyxia. The aim of this paper is to show the outcomes of diabetic pregnancies in relation to type of diabetes, with special consideration to gestational age, birth weight and early neonatal complications. The data is based on a retrospective observational study of 663 deliveries and 687 neonates at the Department of Gynecology and Obstetrics at the University Hospital Centre Zagreb in 2018. The average gestational age was 38 weeks and 5 days, the average birth weight 3437,78 g, with a higher percentage of premature births (28,87%) and cesarean sections (42,84%) than in the general population. The percentage of large-for-gestational-age infants was 14,85%. Cardiovascular, urogenital and gastrointestinal malformations were registered in small numbers, and neonatal jaundice was the most frequent postnatal complication (3,2%). A relatively low occurence of complications, especially in the case of pregnancies complicated by GDM, implies the the importance of good prenatal care in the case of pregnant women with diabetes mellitus.