What is the recommended management for diabetes in pregnancy?

Management of Diabetes in Pregnancy

Optimal management of diabetes in pregnancy requires strict glycemic control with target fasting glucose 70-95 mg/dL, 1-hour postprandial glucose <140 mg/dL, and 2-hour postprandial glucose <120 mg/dL, along with an A1C goal <6% if achievable without significant hypoglycemia. 1

Preconception Care

Preconception care is critical for women with preexisting diabetes and should include:

• Glycemic targets: Aim for A1C <6.5% before conception to minimize risk of congenital anomalies 1
• Medication review: Discontinue potentially harmful medications including ACE inhibitors, angiotensin receptor blockers, and statins 1
• Screening: Complete comprehensive eye exam, renal function assessment, and evaluation for other diabetes complications 1
• Supplementation: Prescribe high-dose folate (5 mg daily) 2
• Education: Provide comprehensive counseling on risks to mother and fetus related to diabetes in pregnancy 1

Monitoring During Pregnancy

Blood Glucose Monitoring

• Self-monitoring: Fasting and postprandial monitoring is essential 1
• Targets:
  • Fasting: 70-95 mg/dL (3.9-5.3 mmol/L)
  • 1-hour postprandial: 110-140 mg/dL (6.1-7.8 mmol/L)
  • 2-hour postprandial: 100-120 mg/dL (5.6-6.7 mmol/L) 1

A1C Monitoring

• Target: <6% (<42 mmol/mol) if achievable without significant hypoglycemia; may be relaxed to <7% (<53 mmol/mol) if necessary to prevent hypoglycemia 1
• Frequency: Monitor more frequently than usual (e.g., monthly) due to altered red blood cell kinetics during pregnancy 1
• Interpretation: A1C is slightly lower in pregnancy due to increased red blood cell turnover 1

Continuous Glucose Monitoring (CGM)

• Indications: Particularly valuable for type 1 diabetes in pregnancy 1
• Benefits: Reduces macrosomia and neonatal hypoglycemia in type 1 diabetes 1
• Usage: Should be used as an adjunct to, not a replacement for, self-monitoring of blood glucose 1

Insulin Management

Physiological Changes and Insulin Requirements

• First trimester: Enhanced insulin sensitivity with 9-18% decrease in insulin requirements between weeks 7-15 3
• Second trimester: Insulin resistance increases, requiring weekly or biweekly dose increases 1
• Third trimester: Insulin requirements may double compared to pre-pregnancy needs 1
• Late pregnancy: Rapid reduction in insulin requirements may indicate placental insufficiency requiring immediate evaluation 3

Insulin Regimen

• Preferred approach: Physiologic basal-bolus dosing to mimic endogenous insulin patterns 4
• Distribution: Smaller proportion as basal insulin and greater proportion as prandial insulin 1
• Adjustments: Frequent titration based on blood glucose monitoring results 4

Medical Nutrition Therapy and Lifestyle Management

• Carbohydrate consistency: Essential to match with insulin dosage and avoid glycemic excursions 1
• Referral: All pregnant women with diabetes should be referred to a registered dietitian 1
• Weight gain goals: Individualized based on pre-pregnancy BMI 1
• Physical activity: Regular moderate exercise is recommended 1

Monitoring for Complications

• Retinopathy: Dilated eye examinations before pregnancy or in first trimester, then every trimester and for 1 year postpartum 1
• Diabetic ketoacidosis (DKA): Monitor for DKA, which can occur at lower blood glucose levels during pregnancy 3
• Fetal surveillance: Ultrasound for fetal morphology at 18-20 weeks, cardiac views at 24 weeks if required, and fetal growth at 28-30 and 34-36 weeks 2

Postpartum Management

• Insulin requirements: Fall rapidly during labor and postpartum period, requiring close monitoring and adjustment 2
• Breastfeeding: All women should be supported in attempts to breastfeed 1
• Contraception: Discuss contraceptive options to prevent unplanned pregnancy until glycemic targets are achieved 1

Common Pitfalls and Caveats

• First trimester hypoglycemia: Failure to anticipate and adjust for decreased insulin requirements can lead to severe hypoglycemia 3
• Diabetic ketoacidosis: Can occur at lower blood glucose levels during pregnancy and requires prompt recognition and treatment 3
• A1C interpretation: Standard estimated A1C calculations from CGM data should not be used in pregnancy 1
• Postpartum insulin adjustment: Rapid decrease in insulin requirements postpartum requires vigilant monitoring to prevent hypoglycemia 2

By implementing these comprehensive management strategies, the risks of adverse maternal and fetal outcomes associated with diabetes in pregnancy can be significantly reduced.