What are the guidelines for induction of labor in an overt diabetic mother with well-controlled blood glucose levels?

Guidelines for Induction of Labor in an Overt Diabetic Mother

For women with overt diabetes and well-controlled blood glucose levels, induction of labor is recommended during the 39th week of gestation (39/0 to 39/6 weeks) to optimize maternal and fetal outcomes.

Timing of Delivery

• Delivery during the 39th week of gestation provides the best balance of maternal and fetal outcomes for diabetic mothers with well-controlled blood glucose levels 1
• Prolongation of gestation past 38 weeks increases the risk of fetal macrosomia without reducing cesarean rates, so delivery during the 38th week is recommended unless obstetric considerations dictate otherwise 2
• For women with well-controlled gestational diabetes using only lifestyle modifications, delivery can be considered between 39/0 and 40/6 weeks of gestation 1
• For women requiring medication (insulin or oral agents) to control their diabetes, the ideal delivery window is 39/0 to 39/6 weeks of gestation 1
• There is no evidence supporting delivery before 38 weeks' gestation in the absence of objective evidence of maternal or fetal compromise 2

Indications for Earlier Delivery

• Delivery before 39 weeks may be indicated in cases of:
  • Poor glycemic control (fasting glucose levels exceeding 105 mg/dl or 5.8 mmol/l) 2
  • Hypertensive disorders 2
  • Evidence of fetal compromise 2
  • Estimated fetal weight >4,000g (to reduce risk of shoulder dystocia) 3, 4

Fetal Surveillance

• Increased surveillance is appropriate for pregnancies at risk for fetal demise, particularly when:
  • Fasting glucose levels exceed 105 mg/dl (5.8 mmol/l) 2
  • Pregnancy progresses past term 2
• For patients with poor glucose control or who require medications, fetal surveillance should begin at 32 weeks of gestation 1
• Mothers should be taught to monitor fetal movements during the last 8-10 weeks of pregnancy and report any reduction immediately 2

Mode of Delivery

• Diabetes alone is not an indication for cesarean delivery 2
• Consider elective cesarean delivery if estimated fetal weight exceeds 4,500g to reduce risk of birth trauma 1
• Studies show that maintaining strict glycemic control combined with an active management protocol for early elective delivery based on estimated fetal weight can significantly reduce rates of macrosomia, traumatic births, and cesarean deliveries 3

Intrapartum Management

• Blood glucose monitoring during labor is recommended for women treated with insulin or oral hypoglycemic agents to:
  • Guide correction of maternal hyperglycemia 2
  • Prevent fetal hypoxia 2
  • Prevent neonatal hypoglycemia 2
• Although the ideal target glucose concentration during labor has not been firmly established, maintaining levels between 5-10 mmol/L (90-180 mg/dL) is generally recommended 2

Special Considerations

• Use of corticosteroids for fetal lung maturity (when indicated) should not be withheld due to diabetes, but will require intensified monitoring of maternal glucose levels and possible temporary addition or increase of insulin doses 2
• Oxytocin may be used for induction of labor in diabetic mothers, as it is indicated for induction of labor in patients with maternal diabetes when delivery is in the best interest of mother and fetus 5

Postpartum Follow-up

• Women with diabetes should be tested for persistent diabetes at 4-12 weeks postpartum using a 75-g oral glucose tolerance test 2, 6
• Lifelong screening for diabetes should be performed at least every 3 years 2, 6
• Breastfeeding should be encouraged in women with diabetes 2

Potential Complications to Monitor

• Increased risk of hypertensive disorders 2
• Macrosomia and large-for-gestational-age infants 2, 7
• Shoulder dystocia 7, 4
• Neonatal hypoglycemia 2
• Neonatal respiratory distress 2

By following these guidelines for timing of induction and careful management during labor, the risks associated with diabetes in pregnancy can be minimized, leading to improved outcomes for both mother and baby.