Overview

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. Expectant mothers 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.

In women with gestational diabetes, blood sugar usually returns to normal 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.

Symptoms

For most women, gestational diabetes doesn't cause noticeable signs or symptoms. Increased thirst and more-frequent urination are possible symptoms.

When to see a doctor

If possible, seek health care early — when you first think about trying to get pregnant — so your doctor can check your risk of gestational diabetes along with your overall wellness. Once you're pregnant, your doctor 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 doctor will monitor your blood sugar level and your baby's health.

Causes

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

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

Risk factors

Some women have a greater risk of gestational diabetes. Risk factors for gestational diabetes include the following:

  • Overweight and obesity.
  • A lack of physical activity.
  • Previous gestational diabetes or prediabetes.
  • Polycystic ovary syndrome.
  • Diabetes in an immediate family member.
  • Previously delivering a baby weighing more than 9 pounds (4.1 kilograms).
  • Nonwhite race — Women who are black, American Indian, Asian American and Pacific Islander and those of Hispanic descent have a higher risk of developing gestational diabetes.

Complications

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 C-section to deliver.

Complications that may affect your baby

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

  • Excessive birth weight. Higher than normal blood sugar in mothers can cause their babies 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 women's 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 to mothers with gestational diabetes may experience respiratory distress syndrome — a condition that makes breathing difficult.
  • Low blood sugar (hypoglycemia). Sometimes babies of mothers with gestational diabetes 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 of mothers who have gestational diabetes 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 the lives of both mother and baby.
  • 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 type 2 diabetes as you get older.

Prevention

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 too.
  • 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 normal and healthy. But gaining too much weight too quickly can up your risk of gestational diabetes. Ask your doctor what a reasonable amount of weight gain is for you.

Feb. 27, 2020
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