GD Clinical Care Guidelines

Gestational diabetes (GD) is any degree of glucose intolerance with onset or first recognition during pregnancy.

Detection

Screening should be performed between the 24th and 28th weeks of gestation in women who meet one or more of the following criteria:

• 25 years old or more;

• less than 25 years old and obese;

• family history of diabetes in first-degree relatives;

• member of an ethnic/racial group with a high prevalence of diabetes (e.g. Hispanic, Native American, African-American or Pacific Islander).

Screening test

A 50 g oral glucose load followed by plasma glucose determination one hour later. A value of 140 mg/dL or more one hour after the load indicates need for a full diagnostic 100 g three-hour fasting glucose tolerance test.

Diagnosis

The diagnosis of GD requires any two of the four following plasma glucose values after the OGTT:

• 165 mg/dL fasting;

• 190 mg/dL after one hour;

• 165 mg/dL after two hours;

• 145 mg/dL after three hours.

Management

Insulin is the only pharmacologic therapy shown to reduce fetal morbidities when added to medical nutrition therapy. Insulin therapy is indicated when medical nutrition therapy fails to maintain fasting blood glucose levels less than 95 mg/dL or two-hour postprandial levels less than 120 mg/dL.

Long-term considerations

Maternal blood glucose should be monitored six weeks after delivery. If blood glucose levels are normal at that time, re-assessment of glycemia should be undertaken at a minimum of three-year intervals. Women with impaired fasting glucose should be tested at more frequent intervals. Offspring of women with GD should be followed closely for the development of obesity and/or abnormalities of glucose tolerance.

Source: American Diabetes Association, Alexandria, VA.