[Clinical practice recommendations for diabetes in pregnancy (Update 2019)]

In 1989 the St. Vincent Declaration aimed to achieve comparable pregnancy outcomes in diabetic and non-diabetic women. However, currently women with pre-gestational diabetes still feature a higher risk of perinatal morbidity and even increased mortality. This fact is mostly ascribed to a persistently low rate of pregnancy planning and pre-pregnancy care with optimization of metabolic control prior to conception. All women should be experienced in the management of their therapy and on stable glycemic control prior to the conception. In addition, thyroid dysfunction, hypertension as well as the presence of diabetic complications should be excluded before pregnancy or treated adequately in order to decrease the risk for a progression of complications during pregnancy as well as maternal and fetal morbidity. Especially in women with type 1 diabetes mellitus in early pregnancy the risk of hypoglycemia is highest and decreases with the progression of pregnancy due to hormonal changes causing steady increase of insulin resistance. In addition, obesity increases worldwide and contributes to increasing numbers of women at childbearing age with type 2 diabetes mellitus and further deterioration of pregnancy outcomes in diabetic women. Maternal glycemic control should aim to achieve normoglycemia and normal HbA_1c levels, possibly without hypoglycemia, but is associated with the development of diabetic embryopathy and fetopathy if dysglycemia occurs. Intensified insulin therapy with multiple daily insulin injections and pump treatment are effective in reaching good metabolic control during pregnancy. Oral glucose lowering drugs (Metformin) may be considered in obese women with type 2 diabetes mellitus to increase insulin sensitivity but should be also prescribed cautiously due to crossing the placenta and lack of long-time follow up data of the offspring.