Pregnancy in a Diabetic Patient. Labor and Delivery

For most women with diabetes, pregnancy can be brought to term with a normal vaginal delivery if there has been good control of glucose levels. Women with poor diabetic control, especially with nephropathy, hypertension, growth-retarded fetuses and some macrosomic fetuses, may need to be delivered earlier. Although many regimens have been suggested for attaining glucose control during labor and delivery, including subcutaneous insulin, control of plasma glucose is easier when insulin is administered as a continuous infusion for women with type 1 and type 2 diabetes. Usually, the patient is hospitalized the day prior to induction of labor and is given her usual diet and insulin dose. The morning after, breakfast and insulin are withheld, and baseline glucose is measured. An intravenous infusion is initiated with dextrose 5% or 10% in water at 125 cc/hr, using an infusion pump. A separate insulin infusion (1 U/10 mL) should also be initiated at the same time. Table 9 provides a guide for the insulin dose to be administered initially, based on the capillary glucose level.

During labor, the glucose level and insulin doses should be monitored and adjusted hourly to maintain a normal glucose level of 70­-120 mg/dL. For spontaneous labor, the same procedure is followed. However, if the patient has taken an intermediate-acting insulin in the previous 12 hours, the insulin requirements may be less. Patients with fever, infection, or other complications require higher doses, as do obese patients with type 2 diabetes who have required greater than 100 units of insulin/day prepartum. For patients in whom perinatal complications and/or poor diabetic control necessitates a cesarean section, the breakfast meal and the morning insulin dose are omitted. During surgery, separate dextrose and insulin infusions, as mentioned above, should be utilized and continued until the patient has bowel sounds and is able to eat without vomiting.

Shoulder dystocia is a main concern for these fetuses and is a major reason for cesarean section. The incidence of shoulder dystocia is directly related to fetal size, with a 10% incidence if the fetus weighs more than 4.5 kg.Various maneuvers exist in dealing with this problem. Planned cesarean delivery may be a good strategy for diabetic pregnant women with estimated fetal weights greater than 4.25 kg.