Diagnosis

If you're at average risk of gestational diabetes, you'll likely have a screening test during your second trimester — between 24 and 28 weeks of pregnancy.

If you're at high risk of diabetes — for example, if you're overweight or obese before pregnancy or you have a mother, father, sibling or child with diabetes — your doctor may test for diabetes early in pregnancy, likely at your first prenatal visit.

Routine screening for gestational diabetes

Screening tests may vary slightly depending on your health care provider, but generally include:

  • Initial glucose challenge test. You'll drink a syrupy glucose solution. One hour later, you'll have a blood test to measure your blood sugar level. A blood sugar level of 190 milligrams per deciliter (mg/dL), or 10.6 millimoles per liter (mmol/L) indicates gestational diabetes.

    A blood sugar below 140 mg/dL (7.8 mmol/L) is usually considered normal on a glucose challenge test, although this may vary by clinic or lab. If your blood sugar level is higher than normal, you'll need another glucose tolerance test to determine if you have the condition.

  • Follow-up glucose tolerance testing. This test is similar to the initial test — except the sweet solution will have even more sugar and your blood sugar will be checked every hour for three hours. If at least two of the blood sugar readings are higher than expected, you'll be diagnosed with gestational diabetes.

Treatment

Treatment for gestational diabetes includes:

  • Lifestyle changes
  • Blood sugar monitoring
  • Medication, if necessary

Managing your blood sugar levels helps keep you and your baby healthy. Close management can also help you avoid complications during pregnancy and delivery.

Lifestyle changes

Your lifestyle — how you eat and move — is an important part of keeping your blood sugar levels in a healthy range. Doctors don't advise losing weight during pregnancy — your body is working hard to support your growing baby. But your doctor can help you set weight gain goals based on your weight before pregnancy.

Healthy diet

A healthy diet focuses on fruits, vegetables, whole grains and lean protein — foods that are high in nutrition and fiber and low in fat and calories — and limits highly refined carbohydrates, including sweets. A registered dietitian or a diabetes educator can help you create a meal plan based on your current weight, pregnancy weight gain goals, blood sugar level, exercise habits, food preferences and budget.

Stay active

Regular physical activity plays a key role in every woman's wellness plan before, during and after pregnancy. Exercise lowers your blood sugar, and as an added bonus, regular exercise can help relieve some common discomforts of pregnancy, including back pain, muscle cramps, swelling, constipation and trouble sleeping.

With your doctor's OK, aim for 30 minutes of moderate exercise on most days of the week. If you haven't been active for a while, start slowly and build up gradually. Walking, cycling and swimming are good choices during pregnancy. Everyday activities such as housework and gardening also count.

Monitor your blood sugar

While you're pregnant, your health care team may ask you to check your blood sugar four or more times a day — first thing in the morning and after meals — to make sure your level stays within a healthy range.

Medication

If diet and exercise aren't enough, you may need insulin injections to lower your blood sugar. Between 10% and 20% of women with gestational diabetes need insulin to reach their blood sugar goals. Some doctors prescribe an oral medication to control blood sugar, while others believe more research is needed to confirm that oral drugs are as safe and as effective as injectable insulin to control gestational diabetes.

Close monitoring of your baby

An important part of your treatment plan is close observation of your baby. Your doctor may check your baby's growth and development with repeated ultrasounds or other tests. If you don't go into labor by your due date — or sometimes earlier — your doctor may induce labor. Delivering after your due date may increase the risk of complications for you and your baby.

Follow-up after delivery

Your doctor will check your blood sugar after delivery and again in six to 12 weeks to make sure that your level has returned to normal. If your tests are normal — and most are — you'll need to have your diabetes risk assessed at least every three years.

If future tests indicate type 2 diabetes or prediabetes, talk with your doctor about increasing your prevention efforts or starting a diabetes management plan.

More Information

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this disease.

Coping and support

It's stressful to know you have a condition that can affect your unborn baby's health. But the steps that will help control your blood sugar level — such as eating healthy foods and exercising regularly — can help relieve stress, nourish your baby and help prevent type 2 diabetes in the future.

You may feel better if you learn as much as you can about gestational diabetes. Talk to your health care team, or read books and articles about gestational diabetes. Some women find a support group for women with gestational diabetes helpful.

Preparing for your appointment

You'll likely find out you have gestational diabetes from routine screening during your pregnancy. Your doctor may refer you to additional health professionals who specialize in diabetes, such as an endocrinologist, a registered dietitian or a diabetes educator. They can help you learn to manage your blood sugar level during your pregnancy.

Here's some information to help you get ready for your appointment and know what to expect from your doctor or other health professional.

What you can do

  • Be aware of pre-appointment restrictions. When you make your appointment, ask if you need to fast for lab tests or do anything else to prepare for diagnostic tests.
  • Write down symptoms you're having, including those that may seem unrelated to gestational diabetes. You may not have noticeable symptoms, but it's good to keep a log of anything unusual you notice.
  • Write down key personal information, including major stresses or recent life changes.
  • Make a list of all medications, including over-the-counter drugs and vitamins or supplements you're taking.
  • Take a family member or friend along, if possible. Someone who accompanies you may remember something that you missed or forgot.

Questions to ask your doctor

Make a list of questions to help make the most of your time with your doctor. For gestational diabetes, some basic questions to ask your doctor include:

  • What can I do to help control my condition?
  • Can you recommend a dietitian or diabetes educator who can help me plan meals, an exercise program and coping strategies?
  • Will I need medication to control my blood sugar?
  • What symptoms should prompt me to seek medical attention?
  • Are there brochures or other printed materials I can take? What websites do you recommend?

What to expect from your doctor

Your doctor is also likely to have questions for you, especially if you're seeing him or her for the first time. Your doctor may ask:

  • Have you experienced increased thirst or excessive urination? If so, when did these symptoms start? How often do you have them?
  • Have you noticed other unusual symptoms?
  • Do you have a parent or sibling who's ever been diagnosed with diabetes?
  • Have you been pregnant before? Did you have gestational diabetes during your previous pregnancies?
  • Did you have other problems in earlier pregnancies?
  • If you have other children, how much did each weigh at birth?
Aug. 26, 2020
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