What is the recommended glucose monitoring and insulin management plan for patients with pregestational diabetes (diabetes diagnosed before pregnancy) on an insulin plan during the immediate postpartum period and up to 6 weeks postpartum?

Postpartum Glucose Monitoring and Insulin Management for Pregestational Diabetes

For patients with pregestational diabetes who were on insulin during pregnancy, insulin requirements decrease dramatically immediately postpartum to approximately 34% lower than prepregnancy requirements, with insulin sensitivity returning to prepregnancy levels over 1-2 weeks. 1

Immediate Postpartum Period (First 48 Hours)

Type 1 Diabetes

• Resume the basal-bolus insulin scheme immediately after delivery, with a significant reduction in insulin dosage 1:
  • Use either 80% of pre-pregnancy insulin doses OR
  • Use 50% of the doses used at the end of pregnancy 1
• Never discontinue basal insulin in Type 1 diabetes patients due to high risk of ketoacidosis 1
• If the patient was on an insulin pump, restart it as soon as any IV insulin is discontinued 1
• Target blood glucose range should be 6-8.8 mmol/L (110-160 mg/dL) after vaginal delivery, with slightly lower targets after cesarean section to support wound healing 1

Type 2 Diabetes

• Continue insulin at half the pregnancy dose while awaiting diabetologist consultation 1
• Monitor blood glucose before meals and 2 hours after meals 1
• Maintain the same target glucose range as Type 1 diabetes (6-8.8 mmol/L or 110-160 mg/dL) 1

Monitoring Schedule During First Week Postpartum

• Check fasting and 2-hour postprandial glucose levels at least 4 times daily during the first week 1
• Pay particular attention to hypoglycemia prevention, especially in the setting of breastfeeding and erratic sleep and eating schedules 1
• Breastfeeding can reduce insulin requirements in the postpartum period and may require additional insulin adjustments 2

Weeks 1-6 Postpartum

• Insulin sensitivity returns to prepregnancy levels over 1-2 weeks after delivery 1
• Continue monitoring blood glucose before and after meals, but frequency can be reduced as glycemic patterns stabilize 1
• Adjust insulin doses based on blood glucose patterns, with the expectation that requirements will gradually increase toward prepregnancy levels 1
• For patients with Type 2 diabetes who are not breastfeeding, oral antidiabetic medications may be considered after consultation with a diabetologist 1

6-Week Postpartum Assessment

• Schedule a comprehensive diabetology evaluation before discharge from postpartum care 1
• Perform the following assessments at 4-12 weeks postpartum 1:
  • HbA1c
  • Fasting blood glucose
  • 75g oral glucose tolerance test (OGTT) using non-pregnancy criteria 1
• OGTT is recommended over HbA1c at 4-12 weeks postpartum because HbA1c may be persistently impacted (lowered) by increased red blood cell turnover related to pregnancy and blood loss at delivery 1

Special Considerations

Breastfeeding

• Support all women with diabetes in attempts to breastfeed 1
• Be aware that lactation increases the risk of overnight hypoglycemia and may require insulin dose adjustments 1
• Breastfeeding mothers with diabetes may require lower insulin doses compared to non-breastfeeding mothers 2

Contraception

• Discuss and implement a contraceptive plan with all women with diabetes of reproductive potential 1
• Long-acting, reversible contraception may be ideal for many women 1

Common Pitfalls and Caveats

1. Never discontinue basal insulin in Type 1 diabetes patients - this can lead to rapid development of ketoacidosis 1
2. Avoid excessive insulin dosing - insulin requirements drop dramatically after placental delivery 1
3. Don't overlook hypoglycemia risk - especially during breastfeeding and with irregular sleep patterns 1
4. Don't delay postpartum testing - schedule the 75g OGTT at 4-12 weeks postpartum to evaluate for persistent diabetes 1
5. Don't use the same glucose targets as during pregnancy - postpartum targets are less strict than pregnancy targets 1

By following these guidelines, you can effectively manage the transition from pregnancy to postpartum glucose control in patients with pregestational diabetes who were on insulin during pregnancy.