Читать книгу Clinical Pharmacology and Therapeutics - Группа авторов - Страница 103

Diabetes in pregnancy is divided primarily into pre‐existing diabetes (type 1 and type 2) and gestational diabetes. Diabetes is associated with increased risk for both the mother and the foetus and the most important goal of treatment is to achieve as near to normoglycaemia in the mother as possible to reduce these risks. For type 1 and type 2 diabetes, tight diabetic control is achieved ideally pre‐pregnancy to reduce the risk of congenital malformations. For type 1 diabetes, insulin pump with variable basal background insulin rate and ability to deliver boluses with meals and many will be on as standard, a four times daily basal bolus regimen such as an intermediate acting insulin to be taken at night and three pre‐meal injections of fast‐acting insulin allow maximum flexibility. As pregnancy progresses, there will be increased insulin requirements which rapidly returns to pre‐pregnancy levels post‐delivery. The short‐acting insulin analogues, insulin aspart and insulin lispro, are not known to be harmful, and may be used during pregnancy and lactation. The safety of long‐acting insulin analogues in pregnancy has not been established, therefore isophane insulin is recommended where longer‐acting insulins are needed. Insulin is adjusted based mainly on post‐prandial blood glucose monitoring (1 hour < 7.8 mmol/L) and fasting levels (3.5–5.9 mmol/L).

Women with type 2 diabetes are usually converted to insulin either pre‐pregnancy or in early pregnancy, with the aim of optimising glycaemic control. The sulphonylureas are generally avoided in pregnancy as they cross the placenta and theoretically cause neonatal hypoglycaemia. The thiazolidinediones are contraindicated due to teratogenesis in animal studies. Metformin can be used either alone or in combination with insulin in type 2 and gestational diabetics. However, at present the long‐term effects of metformin on the foetus are not known.