If your blood sugar level is too high when you are pregnant, you have gestational diabetes. Gestational diabetes usually goes away after the baby is born and affects about 4% of pregnancies in the U.S.
High blood sugar can cause problems for you and your baby. With gestational diabetes, your baby may grow too large, which can cause problems during delivery. Your baby may also be born with low blood sugar. But with treatment, most women with gestational diabetes are able to control their blood sugar and give birth to healthy babies.
Women who have had gestational diabetes are more likely than other women to develop type 2 diabetes later on. You may be able to prevent type 2 diabetes if you stay at a healthy weight, eat healthy foods, and exercise.
Causes of Gestational Diabetes
The pancreas makes a hormone called insulin. Insulin helps your body properly use and store the sugar from the food you eat. This keeps your blood sugar level in a safe range. When you are pregnant, your body makes other hormones that can make it harder for insulin to work. This deterioration of insulin's actions is normal in pregnancy, but tends to get worse during the third trimester.
A pregnant woman can get diabetes when her pancreas cannot make enough insulin to keep her blood sugar levels within a safe range.
Symptoms of Gestational Diabetes
Many women are surprised to learn they have gestational diabetes, because they do not have symptoms.
If you do have symptoms of gestational diabetes, they can include:
- Increased thirst
- Increased urination
- Increased hunger
- Blurred vision
Having these symptoms does not always mean that you have gestational diabetes, but it is important to get tested, because high blood sugar can cause problems for both you and your baby.
Diagnosing Gestational Diabetes
All women should be tested for gestational diabetes between the 24th and 28th weeks of pregnancy. If your doctor thinks you are more likely to get gestational diabetes, you may be tested earlier. Women at a high risk for developing gestational diabetes include those who are obese, have a history of gestational diabetes, have sugar in their urine, or have a strong family history of diabetes. If they have an initial evaluation that shows no detectable elevated sugar, a later test (at 24-28 weeks) may be ordered to reassess.
Gestational diabetes is diagnosed with two blood tests. In the first test, your blood sugar level is tested one hour after you drink a small cup of a sweet liquid. If your blood sugar is too high, you will need to do a longer, three-hour glucose test. If your blood sugar is still above a certain level, you have gestational diabetes.