Significance

• An oral glucose-tolerance screening test is typically performed between weeks 24 and 28 of pregnancy. This is the screening test for gestational diabetes
  
  

Features

• Gestational diabetes is defined as high glucose levels that occur during pregnancy in a woman who was not diagnosed with diabetes prior to pregnancy. The American Diabetes Association reports that annually, approximately 4 percent of all pregnant women are diagnosed with gestational diabetes.
  
  

Identification

• The oral glucose-tolerance screening test measures how well the body processes glucose by checking blood glucose levels after the woman drinks a glucose-containing solution. If the lab work indicates a blood glucose level of 130 mg/dL or higher, a second oral glucose-tolerance test is ordered, in which the glucose level is checked in a series of measurements in order to rule out or confirm a diagnosis of gestational diabetes.
  
  

Considerations

• Elevated glucose levels due to gestational diabetes do not cause fetal deformities, but can increase the risk of the infant having significantly low glucose levels at birth. Babies born to mothers with gestational diabetes tend to be larger at birth, which places them at risk for injury during birth.
  
  

Warning

• Once a woman gives birth, her glucose levels usually return to normal. However, gestational diabetes can increase the risk of developing type 2 diabetes later in life.