[Insulin therapy in type 1 diabetes for and during pregnancy: by which means and for which objectives?]

Clinical data in the 1980s showed a close relationship between the conceptional glycated hemoglobin and the occurrence of spontaneous early abortions and fetal malformations. Blood glucose level during pregnancy was similarly correlated with the risk of fetal macrosomia, due to significant links between birthweight, fetal hyperinsulinemia and mean maternal blood glucose. Tight blood glucose control from conception to term was shown to be able to lower the risk of fetal malformations and perinatal mortality to that of the offspring of a non diabetic mother. Prerequisites include: 1) contraception until tight blood glucose control, 2) close partnership between diabetologist and obstetrician, 3) assessment of diabetic complications. Seldom, coronary heart disease or advanced nephropathy contraindicate pregnancy. Uncontrolled proliferative or pre-proliferative retinopathy, or macular edema, are temporary contraindications to pregnancy. Laser photocoagulation must then be performed before tightening blood glucose control. A complete review of diabetes management is associated with therapeutic intensification. Blood glucose objectives allow as limits: 70 to 100 mg/dl before meals, up to 140 mg/dl one hour and 120 mg/dl two hours after meals. HbA1c allowing conception is close to 7%. Blood glucose monitoring requires 6-7 measurements per day. The most efficient insulin regimens include 3 to 4 shots per day. The distribution between regular and NPH or lente insulins is adapted individually. Lispro insulin, now appearing as safe, may be used to improve post-meal blood glucose control. Insulin pumps may be useful in case of late-night poor control or frequent hypoglycemic events. Patient acceptance of this option is unavoidable to obtain a benefit. Preconceptional insulin therapy must be maintained until pregnancy term. Follow-up must be intensified after twenty fourth week. Labor and delivery, cesarean section, fetal maturation by corticosteroids and use of i.v. betamimetic drugs require continuous i.v. insulin delivery. The continuation of intensive insulin management in post-partum is encouraged.