Gestational diabetes is diabetes diagnosed for the first time during pregnancy (gestation). Like other types of diabetes, gestational diabetes affects how your cells use sugar (glucose). Gestational diabetes causes high blood sugar that can affect your pregnancy and your baby's health.

While any pregnancy complication is concerning, there's good news. During pregnancy you can help control gestational diabetes by eating healthy foods, exercising and, if necessary, taking medication. Controlling blood sugar can keep you and your baby healthy and prevent a difficult delivery.

If you have gestational diabetes during pregnancy, generally your blood sugar returns to its usual level soon after delivery. But if you've had gestational diabetes, you have a higher risk of getting type 2 diabetes. You'll need to be tested for changes in blood sugar more often.

Most of the time, gestational diabetes doesn't cause noticeable signs or symptoms. Increased thirst and more-frequent urination are possible symptoms.

If possible, seek health care early — when you first think about trying to get pregnant — so your health care provider can check your risk of gestational diabetes along with your overall wellness. Once you're pregnant, your health care provider will check you for gestational diabetes as part of your prenatal care.

If you develop gestational diabetes, you may need checkups more often. These are most likely to occur during the last three months of pregnancy, when your health care provider will monitor your blood sugar level and your baby's health.

Researchers don't yet know why some women get gestational diabetes and others don't. Excess weight before pregnancy often plays a role.

Usually, various hormones work to keep blood sugar levels in check. But during pregnancy, hormone levels change, making it harder for the body to process blood sugar efficiently. This makes blood sugar rise.

Risk factors for gestational diabetes include:

• Being overweight or obese
• Not being physically active
• Having prediabetes
• Having had gestational diabetes during a previous pregnancy
• Having polycystic ovary syndrome
• Having an immediate family member with diabetes
• Having previously delivered a baby weighing more than 9 pounds (4.1 kilograms)
• Being of a certain race or ethnicity, such as Black, Hispanic, American Indian and Asian American

Gestational diabetes that's not carefully managed can lead to high blood sugar levels. High blood sugar can cause problems for you and your baby, including an increased likelihood of needing a surgery to deliver (C-section).

Complications that may affect your baby

If you have gestational diabetes, your baby may be at increased risk of:

• Excessive birth weight. If your blood sugar level is higher than the standard range, it can cause your baby to grow too large. Very large babies — those who weigh 9 pounds or more — are more likely to become wedged in the birth canal, have birth injuries or need a C-section birth.
• Early (preterm) birth. High blood sugar may increase the risk of early labor and delivery before the due date. Or early delivery may be recommended because the baby is large.
• Serious breathing difficulties. Babies born early may experience respiratory distress syndrome — a condition that makes breathing difficult.
• Low blood sugar (hypoglycemia). Sometimes babies have low blood sugar (hypoglycemia) shortly after birth. Severe episodes of hypoglycemia may cause seizures in the baby. Prompt feedings and sometimes an intravenous glucose solution can return the baby's blood sugar level to normal.
• Obesity and type 2 diabetes later in life. Babies have a higher risk of developing obesity and type 2 diabetes later in life.
• Stillbirth. Untreated gestational diabetes can result in a baby's death either before or shortly after birth.

Complications that may affect you

Gestational diabetes may also increase your risk of:

• High blood pressure and preeclampsia. Gestational diabetes raises your risk of high blood pressure, as well as preeclampsia — a serious complication of pregnancy that causes high blood pressure and other symptoms that can threaten both your life and your baby's life.
• Having a surgical delivery (C-section). You're more likely to have a C-section if you have gestational diabetes.
• Future diabetes. If you have gestational diabetes, you're more likely to get it again during a future pregnancy. You also have a higher risk of developing type 2 diabetes as you get older.

There are no guarantees when it comes to preventing gestational diabetes — but the more healthy habits you can adopt before pregnancy, the better. If you've had gestational diabetes, these healthy choices may also reduce your risk of having it again in future pregnancies or developing type 2 diabetes in the future.

• Eat healthy foods. Choose foods high in fiber and low in fat and calories. Focus on fruits, vegetables and whole grains. Strive for variety to help you achieve your goals without compromising taste or nutrition. Watch portion sizes.
• Keep active. Exercising before and during pregnancy can help protect you from developing gestational diabetes. Aim for 30 minutes of moderate activity on most days of the week. Take a brisk daily walk. Ride your bike. Swim laps. Short bursts of activity — such as parking further away from the store when you run errands or taking a short walk break — all add up.
• Start pregnancy at a healthy weight. If you're planning to get pregnant, losing extra weight beforehand may help you have a healthier pregnancy. Focus on making lasting changes to your eating habits that can help you through pregnancy, such as eating more vegetables and fruits.
• Don't gain more weight than recommended. Gaining some weight during pregnancy is typical and healthy. But gaining too much weight too quickly can increase your risk of gestational diabetes. Ask your health care provider what a reasonable amount of weight gain is for you.

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; you have a mother, father, sibling or child with diabetes; or you had gestational diabetes during a previous pregnancy — your health care provider 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 level below 140 mg/dL (7.8 mmol/L) is usually considered within the standard range on a glucose challenge test, although this may vary by clinic or lab. If your blood sugar level is higher than expected, you'll need another glucose tolerance test to determine if you have gestational diabetes.

• 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 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. Health care providers usually don't advise losing weight during pregnancy — your body is working hard to support your growing baby. But your health care provider can help you set weight gain goals based on your weight before pregnancy.

Lifestyle changes include:

• 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 certified diabetes care and education specialist 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.
• Staying active. Regular physical activity plays a key role in every wellness plan before, during and after pregnancy. Exercise lowers your blood sugar. 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 health care provider'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.

Blood sugar monitoring

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 to manage your blood sugar levels, you may need insulin injections to lower your blood sugar. A small number of women with gestational diabetes need insulin to reach their blood sugar goals.

Some health care providers prescribe an oral medication to manage blood sugar levels. Other health care providers believe more research is needed to confirm that oral medications are as safe and as effective as injectable insulin to manage gestational diabetes.

Close monitoring of your baby

An important part of your treatment plan is close observation of your baby. Your health care provider 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 health care provider may induce labor. Delivering after your due date may increase the risk of complications for you and your baby.

Follow-up after delivery

Your health care provider will check your blood sugar level after delivery and again in 6 to 12 weeks to make sure that your level has returned to within the standard range. If your tests are back in this range — 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 health care provider about increasing your prevention efforts or starting a diabetes management plan.

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. You may find a support group for people with gestational diabetes helpful. Ask your health care team for suggestions.

You'll likely find out you have gestational diabetes from routine screening during your pregnancy. Your health care provider may refer you to additional health professionals who specialize in diabetes, such as an endocrinologist, a certified diabetes care and education specialist, or a registered dietitian. One or more of these care providers can help you learn to manage your blood sugar level during your pregnancy.

You may want to take a family member or friend along to your appointment, if possible. Someone who accompanies you may remember something that you missed or forgot.

Here's some information to help you get ready for your appointment and know what to expect from your health care provider.

What you can do

Before your appointment:

• 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.
• Make a list of 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.
• Make a list of 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.
• Make a list of questions to help make the most of your time with your health care provider.

Some basic questions to ask your health care provider include:

• What can I do to help control my condition?
• Can you recommend a registered dietitian or certified diabetes care and education specialist 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 health care provider is also likely to have questions for you, especially if it's your first visit. Questions may include:

• 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 previous pregnancies?
• If you have other children, how much did each weigh at birth?