The prevalence of all types of diabetes mellitus is increasing worldwide. Diabetes is a common metabolic complication of pregnancy. For many years, pregnancy complicated by type 1 diabetes was associated with a particularly poor prognosis, and while this has changed dramatically over the last 2 decades, a lot has yet to be done. The continuous relationship between the maternal glucose level and the prevalence of pregnancy complications is well‑documented. The list of outcomes includes congenital malformations, stillbirths, neonatal mortality, macrosomia, hypoglycemia, and many others. Several new therapeutic and monitoring tools have become available over the recent years, for example, short- and long‑acting insulin analogs, personal pumps, and continuous glucose monitoring systems. Interestingly, pregnancy planning and preconception education proved to be particularly effective in improving glycemic control in type 1 diabetic women and achieving therapeutic goals recommended by clinical guidelines. This resulted in the reduction of some maternal and neonatal pregnancy outcomes reported from various populations, but despite this remarkable progress the prevalence of the most common complication, neonatal macrosomia, is still substantially higher than in the newborns of mothers without diabetes. The likely causes of this phenomenon are short episodes of hyperglycemia, particularly postprandial ones, liberal diet, maternal obesity, and substantial weight gain during pregnancy - these potential reasons should be addressed in clinical practice. In the future, new therapeutic devices, such as close‑loop insulin pumps, may help further improve the prognosis in pregnant women with type 1 diabetes.