Gestational Diabetes: Understanding, Screening, and Management

Gestational diabetes is a glucose intolerance disorder first diagnosed during pregnancy. It results from physiological insulin resistance amplified by individual risk factors.

Risk Factors

• Maternal age > 35 years
• Pre-pregnancy BMI > 25
• Personal history of gestational diabetes
• Family history of type 2 diabetes
• Fetal macrosomia in a previous pregnancy

Screening

The 75g oral glucose tolerance test (OGTT) is performed between 24 and 28 weeks of amenorrhea. Diagnostic thresholds (IADPSG criteria) are:

• Fasting: at least 0.92 g/L
• At 1 hour: at least 1.80 g/L
• At 2 hours: at least 1.53 g/L

Risks if Untreated

For the mother: pre-eclampsia, C-section, subsequent type 2 diabetes. For the child: macrosomia (large baby), neonatal hypoglycemia, respiratory distress.

Management

1. Diet: carbohydrate distribution throughout the day, low glycemic index, 3 meals + 2-3 snacks
2. Blood glucose self-monitoring: 4 to 6 measurements/day
3. Physical activity: 30 minutes of walking after meals
4. Insulin: if glycemic targets are not met despite lifestyle and diet measures