Management of Pregestational Diabetes During Labor

Induction Methods

Standard obstetrical indications for induction apply to women with pregestational diabetes, with delivery recommended by 38-39 weeks' gestation to balance the risk of stillbirth against neonatal complications 1
Pregestational diabetes alone is not an indication for cesarean delivery, but careful consideration should be given to estimated fetal weight, especially if >4500g due to increased risk of shoulder dystocia 1
Fetal surveillance should be intensified during the last 8-10 weeks of pregnancy with weekly antenatal testing reasonable after 32 weeks 1
Earlier delivery may be indicated in cases of maternal or fetal compromise, including poor glycemic control, hypertensive disorders, abnormal fetal testing, or evidence of fetal growth restriction 1

Continue the patient's regular diabetes treatment regimen with the same glycemic targets used during pregnancy (fasting <95 mg/dL and either one-hour postprandial <140 mg/dL or two-hour postprandial <120 mg/dL) 2
Monitor blood glucose levels frequently to maintain optimal control 2
For Type 1 and Type 2 diabetes patients: Switch from subcutaneous insulin to intravenous (IV) insulin infusion during active labor 3, 4
For patients using insulin pumps: It is preferable to change to IV insulin treatment, though retention of the insulin pump is possible with a personalized protocol for adaptation of pump output during labor 3, 5
Administer 10% glucose infusion alongside insulin to avoid maternal hypoglycemia and ketosis due to fasting and increased energy demands during active labor 3, 5, 6
For Type 1 diabetes patients: Never interrupt insulin therapy due to high risk of ketosis, even with only moderately elevated blood glucose levels 4, 6

Insulin requirements decrease dramatically immediately after delivery 7
For Type 1 diabetes: Resume the basal-bolus insulin scheme with a significant reduction in dosage - either 80% of pre-pregnancy doses or 50% of the doses used at the end of pregnancy 6, 7
For Type 2 diabetes: Continue insulin at half-dose while awaiting diabetologist advice 6
Target blood glucose range: 6-8.8 mmol/L (110-160 mg/dL) after vaginal delivery, with slightly lower targets after cesarean section to support wound healing 6, 7
Never discontinue basal insulin in Type 1 diabetes patients due to high risk of ketoacidosis 7
Be vigilant for hypoglycemia, especially during breastfeeding and with irregular sleep patterns 7

Interruption of insulin therapy in Type 1 diabetes patients can rapidly lead to ketoacidosis 4, 7
Excessive insulin dosing in the immediate postpartum period can cause severe hypoglycemia, as insulin requirements drop dramatically after placental delivery 7
Inadequate glucose infusion during labor can lead to maternal hypoglycemia and ketosis 3, 6

The American College of Obstetricians and Gynecologists recommends continuation of intravenous insulin-glucose infusion with frequent glucose monitoring to maintain maternal glucose between 4.0-7.0 mmol/L (72-126 mg/dL) during the second stage of labor, as insulin requirements that decreased to zero during first stage labor return during active pushing 8, 9
For Type 1 and Type 2 diabetes, maintain intravenous insulin infusion throughout second stage, with rates typically ranging 0-5 units/hour based on glucose levels 8, 9
Never interrupt insulin therapy in Type 1 diabetes patients due to high risk of ketoacidosis, even with moderately elevated glucose levels 8

For Type 1 diabetes, maintain continuous insulin infusion throughout second stage without interruption, and monitor for signs of ketosis if glucose control becomes difficult 8, 10
For Type 2 diabetes, often require higher insulin doses than Type 1 patients due to insulin resistance, sometimes necessitating concentrated insulin formulations 10, 11

Continue 10% glucose infusion alongside insulin throughout second stage labor to prevent maternal hypoglycemia and ketosis during the high energy demands of active pushing 8, 9

Continue IV insulin-glucose protocol through delivery of the baby, and have plan ready for dramatic insulin dose reduction immediately after placental delivery 8, 9
Prepare to reduce insulin to either 80% of pre-pregnancy doses or 50% of end-pregnancy doses for Type 1 diabetes, as insulin requirements drop dramatically immediately after placental delivery 8, 9