What is the management (Mx) of diabetes in pregnancy?

Management of Diabetes in Pregnancy

All individuals with diabetes who are pregnant or planning pregnancy require interprofessional team care with aggressive preconception optimization targeting A1C <6.5%, strict glycemic monitoring during pregnancy with specific glucose targets, and insulin as first-line pharmacotherapy when lifestyle modifications fail. 1

Preconception Care (Critical for Reducing Morbidity)

Achieve A1C <6.5% (<48 mmol/mol) before conception to minimize the risk of congenital anomalies (anencephaly, microcephaly, congenital heart disease, renal anomalies, caudal regression), preeclampsia, and preterm birth, as organogenesis occurs at 5-8 weeks gestation when many women don't yet know they're pregnant. 1

Interprofessional Team Assembly

• Establish care with an endocrinologist, maternal-fetal medicine specialist, registered dietitian nutritionist, and diabetes care and education specialist before conception. 1
• This multidisciplinary approach has demonstrated improved diabetes and pregnancy outcomes in multiple studies. 1

Medication Review (Prevent Teratogenicity)

Immediately discontinue ACE inhibitors, angiotensin receptor blockers, and statins as these are potentially harmful to the fetus. 1, 2

Baseline Testing

• Obtain A1C, serum creatinine, and urinary albumin-to-creatinine ratio to assess baseline kidney function and glycemic control. 1
• Perform comprehensive dilated eye examination to establish baseline retinopathy status, as diabetic retinopathy can develop or progress during pregnancy. 1, 2

Lifestyle Optimization

• Comprehensive nutrition assessment addressing overweight/obesity or underweight status, meal planning, correction of nutritional deficiencies, caffeine intake, and safe food preparation. 1
• Regular moderate exercise, adequate sleep, and avoidance of hyperthermia (hot tubs). 1
• High-dose folic acid supplementation to reduce neural tube defect risk. 2

Glycemic Targets During Pregnancy

Monitor fasting and postprandial glucose levels (not just A1C) as these are the primary targets during pregnancy. 1, 3, 2

Specific Glucose Targets:

• Fasting plasma glucose: <95 mg/dL (5.3 mmol/L) 1, 2
• 1-hour postprandial: <140 mg/dL (7.8 mmol/L) 1, 3, 2
• 2-hour postprandial: <120 mg/dL (6.7 mmol/L) 1, 2

A1C Target:

• Ideally <6% (42 mmol/mol) if achievable without significant hypoglycemia, recognizing that A1C is slightly lower in normal pregnancy due to increased red blood cell turnover. 1, 2
• Continuous glucose monitoring can help achieve these targets. 2

Pharmacologic Management

Insulin is the preferred first-line medication for managing hyperglycemia in pregnancy when lifestyle modifications (medical nutrition therapy and physical activity) fail to achieve glycemic targets. 3, 4

Insulin Initiation and Dosing:

• Physiologic basal-bolus insulin regimens mimic endogenous insulin release, maintaining basal levels to cover hepatic gluconeogenesis while providing rapid meal-related bolus coverage. 4
• Insulin requirements typically decrease during the first trimester, increase during the second and third trimesters, and rapidly decline after delivery. 5
• Frequent dose adjustments are necessary throughout pregnancy based on glucose monitoring results. 4, 6

Insulin Safety in Pregnancy:

• Insulin lispro (and other rapid-acting insulins) are FDA Pregnancy Category B, with animal studies showing no adverse effects on fetal viability or morphology at therapeutic doses. 5
• Use of insulin is compatible with breastfeeding, though dose adjustments may be required. 5

Monitoring for Complications

Diabetic Retinopathy Surveillance:

Perform dilated eye examinations ideally before pregnancy or in the first trimester, then every trimester, and for 1 year postpartum as indicated by retinopathy severity. 1, 2

Diabetic Ketoacidosis (DKA) Vigilance:

• DKA can occur at lower blood glucose levels during pregnancy than in non-pregnant individuals. 3
• Maintain heightened awareness and lower threshold for evaluation. 3

Preeclampsia Prevention:

Prescribe low-dose aspirin (81 mg/day) by the end of the first trimester to reduce preeclampsia risk in women with diabetes. 3

Delivery Planning

• Develop an individualized care plan for delivery based on maternal glucose control, fetal growth, and any complications. 7
• Timing of delivery depends on these factors and should be determined collaboratively with the maternal-fetal medicine team. 7

Postpartum Management

Immediate Postpartum:

• Insulin resistance decreases dramatically immediately after delivery, requiring rapid insulin dose reduction to prevent hypoglycemia. 3
• Encourage breastfeeding to reduce the risk of maternal type 2 diabetes development. 3

For Gestational Diabetes:

• Screen at 4-12 weeks postpartum using a 75g oral glucose tolerance test to assess for persistent diabetes. 3
• Implement lifelong screening for type 2 diabetes or prediabetes every 1-3 years. 3

Contraception Planning:

• Establish a contraceptive plan for all women with diabetes of reproductive potential to allow for planned, optimized future pregnancies. 3

Common Pitfalls to Avoid

• Do not rely on A1C alone during pregnancy—postprandial glucose monitoring is essential as A1C underestimates glycemic excursions due to increased red blood cell turnover. 1
• Do not continue ACE inhibitors, ARBs, or statins—these must be stopped before conception or immediately upon pregnancy recognition. 1, 2
• Do not delay insulin initiation—when lifestyle modifications fail to achieve targets, insulin should be started promptly to prevent fetal complications. 3, 4
• Do not assume insulin requirements remain stable—they change dramatically across trimesters and postpartum, requiring frequent monitoring and adjustment. 5, 4