Overview:

• Occurs during pregnancy.
• Usually develops halfway through pregnancy.
• Often disappears after childbirth.
• Women with GDM are at increased risk for developing type 2 diabetes later in life.
• Insulin production may be normal, slightly decreased, or ineffective due to receptor resistance.

Causes:

• The exact cause is idiopathic (unknown), but may involve:
  • Insulin resistance due to placental hormones antagonistic to insulin.
  • Pregnant females may not have enough insulin to support both themselves and the fetus.

• Thought to be related to hormones produced by the placenta:
  • These hormones impair insulin action.
  • Can cause hyperglycemia by:
    • Impairing insulin activity
    • Reducing insulin secretion
    • Decreasing tissue response to insulin (insulin resistance)

Risk Factors:

• Age (older age)
• Family history of diabetes
• Overweight/obesity (BMI 30+)
• Genetic predisposition

Diagnostic Blood Tests:

• Glucose challenge test (initial screening)
• Follow-up if high glucose:
  • Oral glucose tolerance test to confirm hyperglycemia.
• Additional monitoring if risk factors are present.

Treatment and Lifestyle Modifications:

• Insulin injections may be prescribed if needed.
• Lifestyle changes are crucial:
  • Healthy diet
  • Regular exercise
  • Stop smoking

Possible Complications:

For Mother

• Prolonged high blood pressure can lead to preeclampsia, eclampsia (hypertension and seizures), and organ ischemia.
• Increased risk of type 2 diabetes in the future (~5-10%).

For Baby

• Low glucose levels in fetal cells can cause seizures.
• High blood pressure may cause organ ischemia.
• Higher birth weight (over 9 pounds) increases risk of overweight and type 2 diabetes later.

Onset and Progression

• Usually slow and insidious.
• Onset typically occurs around 20 weeks gestation, as placental hormone levels rise.

Summary

• GDM is linked to hormonal changes during pregnancy impairing insulin action.
• It can be managed with lifestyle modifications and insulin therapy.
• Close monitoring is necessary to prevent maternal and fetal complications.