Gestational Diabetes

Learn about tests and treatments for, and signs and symptoms of gestational diabetes.

• Gestational diabetes is diabetes that occurs in pregnant women.
• Risk factors for gestational diabetes include
  • obesity,
  • a history of gestational diabetes in a previous pregnancy,
  • a family history of type 2 diabetes, and
  • having prediabetes.
• There are typically no noticeable signs or symptoms associated with gestational diabetes.
• Gestational diabetes can cause the fetus to be larger than normal. Delivery of the baby may be more complicated as a result. The baby is also at risk for developing low blood glucose (hypoglycemia) immediately after birth.
• Following a nutrition plan is the typical treatment for gestational diabetes.
• Maintaining a healthy weight and following a healthy eating plan may be able to help prevent or minimize the risks of gestational diabetes.
• Women with gestational diabetes have an increased risk of developing type 2 diabetes after pregnancy.

Gestational diabetes is diabetes, or high blood sugar levels, that develops during pregnancy. It occurs in about 4% of all pregnancies. It is usually diagnosed in the later stages of pregnancy and often occurs in women who have no prior history of diabetes.

Gestational diabetes is thought to arise because the many changes, hormonal and otherwise, that occur in the body during pregnancy predispose some women to become resistant to insulin. Insulin is a hormone made by specialized cells in the pancreas that allows the body to effectively metabolize glucose for later usage as fuel (energy). When levels of insulin are low, or the body cannot effectively use insulin (i.e., insulin resistance), blood glucose levels rise.

Some degree of insulin resistance and impaired glucose tolerance is normal in late pregnancy. However, in some women, this is enough to produce diabetes during pregnancy, or gestational diabetes.

Several risk factors that can increase your risk of getting gestational diabetes include:

• Obesity
• A history of gestational diabetes in a previous pregnancy
• Previous delivery of an infant with a high birth weight (over 9 pounds)
• A parent or sibling with type 2 diabetes
• A personal history of polycystic ovary syndrome (PCOS)
• African American, American Indian, Asian American, Hispanic, or Pacific Islander American ethnicity
• Having prediabetes

Gestational diabetes typically does not cause any noticeable signs or symptoms. This is why screening tests are so important. Rarely, increased thirst or increased urinary frequency may be noticed.

Gestational diabetes is diagnosed with blood tests. Most pregnant women are tested between the 24th and 28th weeks of pregnancy, but if you have risk factors, your doctor may decide to test earlier in the pregnancy.

Blood testing confirms the diagnosis. A screening glucose tolerance test involves drinking a sugary beverage and having your blood drawn to test the glucose levels an hour later. If the screening test is not normal, you may need additional testing.

Another type of test is an oral glucose challenge test (OGTT). For this test, your baseline blood glucose level is checked and then measured at 1, 2, and sometimes 3 hours after consuming a sugary drink. A blood glucose level of 140mg/dL or higher on this test will identify 80% of women with gestational diabetes. When that cutoff is lowered to 130mg/dL, the identification rate increases to 90%. Women who had a level of blood glucose greater than 130 mg/dL are typically recommended to take another diabetes screening test that requires fasting (not eating anything) before the test.

Glycosylated hemoglobin, or hemoglobin A1c, is another test that may be performed. This test is used to monitor long-term blood glucose levels in people with diabetes. The hemoglobin A1c level offers a measure of the average blood glucose level over the past few months.

All pregnant women should be screened for gestational diabetes during their pregnancy. Most pregnant women are tested between the 24th and 28th weeks of pregnancy.

It is important to receive proper treatment for gestational diabetes because research studies have shown that the incidence of problems and complications is decreased when blood glucose levels are normalized. Treatment for gestational diabetes involves attention to maintaining a proper diet. Nutritional modification is the mainstay of therapy, and many women will achieve adequate glucose control by following a nutritional plan. Regular exercise can also contribute to tight glucose control.

Testing your blood glucose levels at home at specific times or after meals will be recommended to determine if your glucose levels are within acceptable limits. Testing at least four times per day is typical.

You may also be asked to test your urine for ketones, substances that are produced when your body metabolizes fat. Ketones are elevated when the body is unable to use glucose for energy.

If diet and exercise are not sufficient to maintain tight control of your blood glucose levels, it may be necessary to institute insulin therapy. Insulin is the only officially approved medication for treating gestational diabetes in the U.S.; however, oral medications are used by many doctors to control the blood sugar in selected women with gestational diabetes. As the pregnancy progresses, insulin requirements may change and insulin doses may need to be adjusted.

While there is no one specific diet that is recommended for all women with gestational diabetes, following a meal plan can help keep your blood sugar levels under control and avoid complications.

• A nutritionist may help design a meal plan that takes into account individual schedules and preferences.
• Eating a variety of foods is recommended, and it is better to eat smaller portions throughout the day (e.g. 3 small to moderate meals and 2-4 snacks) rather than just a few large meals.
• Many women with gestational diabetes will be advised to eat fewer carbohydrates than in their normal diet and to eat complex carbohydrates that contain fiber. It’s important to limit the consumption of foods containing large amounts of simple sugars.
• High-fiber foods like fresh fruits and vegetables, as well as whole-grain products, are not only nutritious but also effective in keeping blood sugar levels stable.
• Skipping meals is not recommended because this leads to undesirable fluctuations in blood sugar levels.

Most women with gestational diabetes who receive treatment go on to deliver healthy babies. The risk of complications increases when blood glucose levels are not properly controlled. While some women with gestational diabetes will develop type 2 diabetes following delivery, this risk can be reduced by following a good nutritional plan, exercising, and maintaining a healthy weight.

• Women with gestational diabetes have a greater chance of needing a Cesarean birth (C-section), in part due to large infant size.
• Gestational diabetes may increase the risk of preeclampsia, a maternal condition characterized by high blood pressure and protein in the urine.
• Women with gestational diabetes are also at increased risk of having type 2 diabetes after pregnancy.

Women with gestational diabetes who receive proper care typically go on to deliver healthy babies. However, if you have persistently elevated blood glucose levels throughout pregnancy, the fetus will also have elevated blood glucose levels. High blood glucose can cause the fetus to be larger than normal, possibly making delivery more complicated. The baby is also at risk of having low blood glucose (hypoglycemia) immediately after birth.

Other serious complications of poorly controlled gestational diabetes in the newborn can include:

• a greater risk of jaundice,
• an increased risk for respiratory distress syndrome, and
• a higher chance of dying before or following birth.

The baby is also at a greater risk of becoming overweight and developing type 2 diabetes later in life.

If diabetes is present in early pregnancy, there is an increased risk of birth defects and miscarriage compared to that of mothers without diabetes.

Gestational diabetes cannot always be prevented; however, obesity is a prime determinant for developing the disease. Maintaining a healthy weight and following a good nutritional plan both before and during pregnancy can decrease your chances of developing gestational diabetes. Maintaining a healthy weight can also decrease your chances of developing type 2 diabetes following pregnancy.