Pregnancy and Gestational Diabetes

pregnant woman eating fruit on couch

What is gestational diabetes?

Diabetes occurs when blood glucose, also called blood sugar, is too high. The risk of heart problems increases with all types of diabetes.

One form — gestational diabetes — develops during pregnancy. The disease can affect the health of both the mother and the developing baby.

Gestational diabetes affects about 5 out of 100 women. For many, the condition is temporary and resolves itself after delivery. However, some mothers may have more than one pregnancy affected by gestational diabetes.

How is gestational diabetes diagnosed?

Gestational diabetes usually happens in the middle of pregnancy. That’s why health care professionals most often test for it between 24 and 28 weeks.

Several blood tests can be used to diagnose gestational diabetes and to determine how well the body is using glucose. A glucose screening, or tolerance, test involves a blood draw one hour after the mother drinks a sweet liquid. A longer, more complicated test — an oral glucose tolerance test — might also be ordered.

What causes gestational diabetes?

Insulin, a hormone, helps keep blood sugar levels in a normal range. During pregnancy, hormonal and other changes cause the body to not use insulin well, a condition known as insulin resistance. Gestational diabetes happens when the body doesn’t make enough extra insulin to compensate.

Some women have a greater risk of gestational diabetes, and researchers are still learning exactly why. Excess weight before pregnancy and family history often contribute to the condition.

What are the symptoms and risks of gestational diabetes?

For most women, gestational diabetes doesn't cause noticeable signs or symptoms. Increased thirst, tiredness and frequent urination are possible problems linked to the condition.

But gestational diabetes may pose serious risks to both mother and child. These include:

  • Preeclampsia. A severe complication of pregnancy, preeclampsia involves high blood pressure and other dangerous symptoms.

  • Delivery problems. Higher-than-normal blood sugar in pregnant women can cause their babies to grow too big in the womb. This can lead to a pre-term birth, delivery complications or need for a surgical delivery.

  • Low blood sugar (hypoglycemia) in the newborn. Prompt monitoring of the baby after birth will be necessary. An intravenous glucose solution may be needed to normalize the baby's blood sugar level.

  • Greater odds of future health problems. Having gestational diabetes makes women more likely to get it again during a future pregnancy. Plus, both mother and child have a higher risk of developing diabetes later in life.

  • Stillbirth. Untreated gestational diabetes can cause a baby's death either before or shortly after birth.

How is gestational diabetes treated?

Often a healthy diet and exercise can control gestational diabetes. Some women may need to take insulin or other medication to manage the condition.

Gestational diabetes typically goes away soon after delivery. If it does not improve, then it’s called Type 2 diabetes. It’s important for all women who have had gestational diabetes to exercise and eat healthy after pregnancy to prevent or delay onset of Type 2 diabetes.

After delivery, both you and your baby will receive blood tests to measure your blood glucose and determine if additional care is necessary.

How can women reduce their risk of gestational diabetes?

Women can reduce the risks linked to gestational diabetes by:

  • Eating nutritious foods in sensible portions. Pick fruits, vegetables and whole grains that are high in fiber and low in fat and calories.

  • Keeping active. With guidance from your health care team, regular exercise before and during pregnancy is essential.

  • Starting pregnancy at a healthy weight.

  • Staying within a recommended weight. Gaining some weight during pregnancy is normal. But gaining weight too quickly can increase the risk of gestational diabetes.