Insulin is a hormone produced in an organ called the pancreas. The pancreas is below and behind the stomach. Insulin is needed to move blood sugar into the body's cells. Inside the cells, glucose is used for energy. Some of it may be stored for later use. Pregnancy hormones can block insulin from doing its job. When this happens, glucose level may increase in a pregnant woman's blood.

With gestational diabetes:

• There are no symptoms in many cases.
• Mild symptoms may include increased thirst or shakiness. These symptoms are most often not life threatening to the pregnant woman.
• A woman may give birth to a large baby. This can increase the chance of problems with the delivery including an increased risk of requiring a cesarean section for delivery.
• A woman has a higher risk for high blood pressure during pregnancy.

Becoming pregnant when you are at your ideal body weight can help lower your chance of getting gestational diabetes. If you are overweight, try to lose weight before pregnancy.

If you do develop gestational diabetes:

• A healthy diet can keep your blood sugar controlled and may keep you from needing medicine. Healthy eating can also keep you from gaining too much weight in your pregnancy. Too much weight gain can increase your risk for gestational diabetes.
• Your health care provider, nurse, or dietitian will create a diet just for you. Your provider may ask you to keep track of what you eat.
• Exercise will help keep your blood sugar under control. A low-impact activity such as walking is a safe and effective type of exercise. Try walking 1 to 2 miles (1.6 to 3.2 kilometers) at a time, 3 or more times per week. Swimming or using an elliptical machine work just as well. Ask your provider what type of exercise, and how much, is best for you.
• If changing your diet and exercising don't control your blood sugar level, you may need oral medicine (taken by mouth) or insulin therapy (shots).

Women who follow their treatment plan and keep their blood sugar normal or close to normal during their pregnancy should have a good outcome.

Blood sugar that is too high raises the risks for:

• Stillbirth
• Very small baby (fetal growth restriction) or very large baby (macrosomia)
• Difficult labor or cesarean birth (C-section)
• Problems with blood sugar or electrolytes in the baby during the first few days after delivery

You can see how well you are doing by testing your blood sugar level at home. Your provider may ask you to check your blood sugar several times each day.

The most common way to check is by pricking your finger and drawing a drop of blood. Then, you place the blood drop in a monitor (testing machine) that measures your blood glucose. If the result is too high or too low, you will need to closely monitor your blood sugar level.

Your providers will follow your blood sugar level with you. Make sure you know what your blood sugar level should be.

Managing your blood sugar can seem like a lot of work. But many women are motivated by their desire to make sure both they and their baby have the best possible outcome.

Your provider will closely check both you and your baby throughout your pregnancy. This will include:

• Visits with your provider as often as every week
• Ultrasounds that show the size of your baby
• A non-stress test that shows whether your baby is doing well

If you need insulin or oral medicine to control your blood sugar, you may need to have labor induced 1 or 2 weeks before your due date.

High blood sugar levels often go back to normal after delivery. Still, many women with gestational diabetes develop diabetes within 5 to 10 years after giving birth. The risk is greater in obese women.

Women with gestational diabetes should be watched closely after giving birth. They should also continue to get checked at future clinic appointments for signs of diabetes that is persisting.

Talk to your provider about measures you can take to reduce your chance of developing diabetes.

Call your provider for the following diabetes-related problems:

• Your baby seems to be moving less in your belly
• You have blurred vision
• You're more thirsty than normal
• You have nausea and vomiting that won't go away

It's normal to feel stressed or down about being pregnant and having diabetes. But, if these emotions are overwhelming you, call your provider. Your health care team is there to help you.

Pregnancy - gestational diabetes; Prenatal care - gestational diabetes

ACOG Practice Bulletin No. 190: Gestational diabetes mellitus. Obstet Gynecol. 2018;131(2):e49-e64. PMID: 29370047 pubmed.ncbi.nlm.nih.gov/29370047/.

Bodnar LM, Himes KP. Maternal nutrition. In: Lockwood CJ, Copel JA, Dugoff L, et al, eds. Creasy and Resnik's Maternal-Fetal Medicine: Principles and Practice. 9th ed. Philadelphia, PA: Elsevier; 2023:chap 12.

ElSayed NA, Aleppo G, Aroda VR, et al. 15. Management of diabetes in pregnancy: standards of care in diabetes-2023. Diabetes Care. 2023;46(Suppl 1):S254-S266. PMID: 36507645 pubmed.ncbi.nlm.nih.gov/36507645/.

Landon MB, Catalano PM, Gabbe SG. Diabetes mellitus complicating pregnancy. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Philadelphia, PA: Elsevier; 2021:chap 45.

Updated by: John D. Jacobson, MD, Professor Emeritus, Department of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.