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Gestational Diabetes


Gestational diabetes (GDM)

is a type of diabetes that develops during pregnancy, usually in the second or third trimester. GDM causes your blood sugar level to rise too high. This can harm you and your unborn baby. Blood sugar levels usually go back to normal after the baby is born. The cause of GDM is not known. Hormones made by the placenta may cause insulin resistance. Insulin helps move sugar out of the blood so it can be used for energy. Insulin resistance means your pancreas makes insulin, but your body cannot use it. As the placenta grows, more of these hormones are produced. The hormones block insulin and cause your blood sugar level to rise.


Signs and symptoms of GDM include the following:

  • More hunger or thirst than usual
  • Having to urinate often
  • Blurred vision
  • Feeling more tired than usual
  • Bladder, vagina, or skin infections that happen often
  • More weight gain than your healthcare provider suggests during your pregnancy
  • Nausea or vomiting

Seek care immediately if:

  • Your heartbeat is fast and weak, or your breathing is fast and shallow.
  • You are more sleepy than usual or become confused.
  • You have blurred or double vision.
  • Your breath has a fruity, sweet smell.
  • You are shaking or sweating.
  • Your blood sugar level is below 70 mg/dL or above 250 mg/dL and does not improve with treatment.
  • You have a headache, or you are dizzy.

Call your doctor or diabetes care team if:

  • You think your baby is not moving as much as usual.
  • You have more hunger or thirst than usual.
  • You are urinating more often than usual.
  • You have an upset stomach and are vomiting.
  • You have questions or concerns about your condition or care.

The following may increase your risk for GDM:

  • Lack of physical activity, such as exercise
  • A family history of diabetes
  • A history of high blood sugar, blood pressure, or cholesterol levels
  • Being overweight or obese
  • Past delivery of a large baby
  • Glycosuria (sugar in your urine) or polycystic ovary syndrome (PCOS)
  • Being African American, Latino, Native American, Asian American, or Pacific Islander heritage

Manage GDM:

GDM may be controlled with meal planning and physical activity. The goal is to keep your blood sugar level as close to normal, as safely as possible. Your healthcare provider and dietitian will help set up a meal and activity plan for you.

  • Follow your meal plan as directed. Talk to a dietitian or healthcare provider about the best meal plan for you. He or she may recommend that you eat 3 small meals and 2 to 4 snacks every day. Control the amount of carbohydrates (such as bread, cereal, and fruit) you eat at each meal and snack. Too much carbohydrate in 1 meal or snack can cause your blood sugar to rise to a high level. Your dietitian or provider will tell you how much carbohydrate to eat at each meal and snack. Eat foods that are a good source of fiber, such as vegetables and legumes (beans and lentils).

  • Ask your provider about the best physical activity plan for you. Physical activity helps keep your blood sugar level steady. A good goal is to be active for at least 30 minutes, 5 days a week. Low-impact activities such as walking or swimming are effective.


may be needed if your diabetes is not controlled by nutrition and exercise. Insulin is safe to use during pregnancy.

Check your blood sugar level as directed:

  • You will be taught how to check a small drop of blood in a glucose monitor. Ask your healthcare provider when and how often to check your blood sugar level during the day. You may need to check your blood sugar level at least 3 times each day.
    How to check your blood sugar
  • Ask your provider what your blood sugar levels should be before and after you eat. He or she may suggest that your blood sugar level should be at or below 95 mg/dL before you eat. The level may need to be at or below 140 mg/dL 1 hour after you eat or at or below 120 mg/dL 2 hours after you eat. Your provider may give you higher target levels if you are at risk for hypoglycemia. Write down your results, and show them to your provider. He or she may use the results to make changes to your medicine, food, and physical activity schedules.

What else you need to know about GDM:

  • Your A1c level may be checked. A hemoglobin A1c is a blood test that measures your average blood sugar level for the past 2 to 3 months. It is also called an HbA1c or glycohemoglobin test. The level is given as a percentage. An A1c of 6% or lower is usually recommended during pregnancy. If you are at risk for hypoglycemia, your goal may be 7%. Changes to your nutrition, physical activity, or medicine plan may be made to help you reach your goal. Your provider may recommend that you have your A1c checked 1 time each month.
  • Check your blood pressure often. High blood pressure can cause problems with your health and your pregnancy. Blood pressure readings are usually written as 2 numbers. Your systolic blood pressure (the first number) should be between 110 and 129. Your diastolic blood pressure (the second number) should be between 65 and 79.
    How to take a Blood Pressure
  • Maintain a healthy weight. A healthy weight can help you control your GDM. Ask your healthcare provider how much weight is healthy for you to gain during your pregnancy. If you were overweight before you became pregnant, he or she may recommend a safe weight loss plan during pregnancy. Your provider or a dietitian can help you create a healthy meal plan for you and your baby. Do not try to go on a crash diet or try to lose weight without your provider's approval. You may not get enough calories or nutrients for you and your baby.
  • Do not smoke. Nicotine is dangerous for you and your baby and can make it harder to manage GDM. Do not use e-cigarettes or smokeless tobacco in place of cigarettes or to help you quit. They still contain nicotine. Ask your provider for information if you currently smoke and need help quitting.
  • You may need diabetes screening after you give birth. Screening may be done 4 to 12 weeks after your baby is born. This is to check if you have developed diabetes, problems with your fasting glucose levels, or glucose intolerance. You may need other tests or treatment if you have any of these. Testing may be repeated every 1 to 3 years if you had GDM but normal tests within 12 weeks of giving birth.

Follow up with your doctor or diabetes care team as directed:

You will need to have screening tests for diabetes 4 to 12 weeks after you have your baby. You may also need to have tests for diabetes every 1 to 3 years for life. Write down your questions so you remember to ask them during your visits.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Learn more about Gestational Diabetes (Ambulatory Care)

Associated drugs

IBM Watson Micromedex

Symptoms and treatments

Mayo Clinic Reference

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.