Strict control of blood glucose levels should be pursued before conception and maintained throughout the pregnancy (glycohaemoglobin [HbA(1c)] level as close as possible to the reference range). Before conception: high-dose (5 mg daily) folate supplementation should be commenced; oral hypoglycaemic agents should be ceased; and diabetes complications screening should take place. Management should be by a multidisciplinary team experienced in the management of diabetes in pregnancy. Blood glucose monitoring is mandatory during pregnancy, and targets are: fasting 4.0-5.5 mmol/L; postprandial < 8.0 mmol/L at 1 hour; < 7 mmol/L at 2 hours. A first trimester nuchal translucency (possibly with first trimester biochemical screening with pregnancy-associated plasma protein A and beta-human chorionic gonadotropin) should be offered. Ultrasound should be performed for fetal morphology at 18-20 weeks, if required, for cardiac views at 24 weeks and for fetal growth at 28-30 and 34-36 weeks. Induction of labour or operative delivery should be based on obstetric and/or fetal indications. Level 3 neonatal nursing facilities may be required and should be anticipated when birth occurs before 36 weeks, or if there has been poor glycaemic control. Insulin requirements fall rapidly during labour and in the puerperium. At this time, close monitoring and adjustment of insulin therapy is necessary.