Type 2 Diabetes: Risk Factors

Gestational Diabetes

Gestational diabetes is diabetes that first appears during pregnancy. It usually develops during the third trimester of pregnancy. After delivery, blood sugar (glucose) levels generally return to normal, although between one-third and one-half of these women develop type 2 diabetes within 10 years.

Who Gets Gestational Diabetes?

Estimates for the prevalence of gestational diabetes are generally about 4%. Some studies, however, have suggested significantly higher rates. In one German study, 13% of pregnant women were diagnosed with this form of diabetes, including many who did not have any risk factors.

A pregnant woman's risk factors include:

• Family history of diabetes
• African American, Hispanic, Asian, or Pacific Islander ethnicity
• Overweight
• Older than 25 years
• Gestational diabetes with past pregnancy
• Having given birth to a child weighing over 9 pounds
• Diagnosis of pre-diabetes

Who Should Be Tested for Gestational Diabetes?

A number of expert groups recommend that all pregnant women be tested for gestational diabetes between their 24th and 28th week. Pregnant women at high risk for diabetes should be tested earlier. The only women who do not need to be tested are those at very low risk. Generally they have the following characteristics:

• Under 25 years old
• Normal weight
• No first-degree relatives with diabetes
• Not belonging to high-risk ethnic groups

How Serious Is Diabetes During Pregnancy?

Effect of Diabetes on the Fetus. Because glucose crosses the placenta, a woman with diabetes can pass high levels of blood glucose to the fetus. In response, the fetus secretes high level of insulin. Studies indicate that such conditions may effect the developing fetus as soon as it is conceived, placing the unborn child at risk for:

• Excessive fetal weight gain, which can lead to complications during delivery
• Birth defects
• Breathing problems and delayed lung development
• Low blood sugar
• Higher future risk for obesity and diabetes

Effect of Diabetes on the Pregnant Woman. In addition to endangering the fetus, diabetes also presents risks to the pregnant woman.

The most serious potential complications from gestational diabetes are high blood pressure during pregnancy, a condition called preeclampsia that is potentially dangerous. Because gestational diabetes increases the size of the fetus, it is also increases the likelihood that a woman will require a Cesarean delivery. Gestational diabetes also increases the risk that a woman will later develop type 2 diabetes.

How Is Gestational Diabetes Managed?

Some suggestions for preventing complications include:

• In most cases, increases in glucose levels can be managed with diet and exercise. Aerobic exercise before and during pregnancy may lower glucose levels and help protect women at risk or those who have gestational diabetes. (Any pregnant woman should check with her doctor before embarking on a vigorous exercise regimen)
• If a woman with gestational diabetes cannot control her glucose with lifestyle measures, she is usually given insulin.