• Most often diagnosed between 24-28 weeks of pregnancy in 4% of pregnant women.
• If left untreated can result in very large baby (over 9 lbs.), infant low blood sugar at birth, and still births. Chronic maternal high blood pressure (hypertension) and an increased rate of cesarean deliveries may also occur.
• Blood glucose/sugar levels return to normal after delivery in 90% of cases.

Cause:

• Hormones produced by the placenta induce an environment of stress producing an insulin resistant state in the mother (see insulin resistance under Type 2 Diabetes).

Screening Test:

• drinking a 50-gram oral glucose solution followed by a 1-hour blood glucose test.
• If result is equal to or greater than 140 mg/dl, further testing required

Diagnostic Test:

• drinking 100-gram oral glucose solution after an 8 hour fast
• blood sugar test at 1, 2, and 3 hours after
• positive diagnosis requires that any two of the four glucose values obtained during the test meet or exceed the following values:

  - Fasting - 105 mg/dl
  - 1-hour - 190 mg/dl
  - 2-hour - 165 mg/dl
  - 3-hour - 145 mg/dl

Treatment:

• Diet Exercise
• Self Monitoring

  - blood sugar
  - ketones
  - baby's movements in utero

• Education
• Insulin may be needed

Goals of Treatment:

• Maintain normal blood glucose/sugar levels

  - Fasting ≤ 90 mg/dl
  - 1-hour after meals ≤ 120 mg/dl

• Provide a nutritionally adequate diet for pregnancy