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Quick Facts

Diabetes During Pregnancy


The Manual's Editorial Staff

Last full review/revision Jan 2020| Content last modified Jan 2020
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NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
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Diabetes is a disease in which your blood sugar (glucose) levels are too high. Blood sugar is your body’s main source of energy. Your body breaks down all types of foods, including bread, fruit, soda, and pasta, into blood sugar.

The hormone insulin controls your blood sugar. If your body doesn't have enough insulin or isn't responding properly to the insulin, your blood sugar will be too high. High blood sugar can cause many problems for both you and your baby.

Getting diabetes during pregnancy is called gestational diabetes. About 1 in 10 to 1 in 20 pregnant women get gestational diabetes.

  • If you already have diabetes, your diabetes may get worse during pregnancy

  • You can also develop diabetes for the first time while you’re pregnant—this diabetes often goes away after you have your baby

  • Having diabetes during pregnancy can cause serious problems for you and your baby

  • Doctors check all pregnant women to see if they have diabetes during pregnancy

  • Doctors will watch you closely to make sure your blood sugar level stays close to normal

What causes diabetes during pregnancy?

You’re more likely to get gestational diabetes if:

  • You've had it before

  • You’re overweight

  • You have close family members with diabetes

  • You’re Native American, Pacific Islander, Mexican, Indian, or Asian

What problems can diabetes during pregnancy cause?

If untreated, diabetes during pregnancy can raise the chance of:

  • Early miscarriage

  • Stillbirth (death of a baby before or during birth)

  • Serious birth defects

  • Low blood sugar in your baby

  • Jaundice (when the skin and white parts of the eyes look yellow) in your baby

  • Large baby, which may cause problems during vaginal birth or mean you'll need a c-section

  • Preeclampsia (a dangerous type of high blood pressure that happens during pregnancy)

How can doctors tell if I have diabetes during pregnancy?

Doctors check all pregnant women for diabetes using a blood test. Most doctors recommend a glucose tolerance test. In this test:

  • You drink a very sugary drink that has a lot of glucose

  • One hour later, doctors will take a sample of blood and test the blood sugar level

  • If the blood sugar is very high, you have gestational diabetes

  • If your blood sugar is only a little high, doctors repeat the test with even more glucose in the drink and measure your blood sugar after 3 hours

Sometimes, doctors just measure your blood sugar without having you drink a sugary drink. This is quicker and easier but isn't as accurate.

How do doctors treat diabetes during pregnancy?

Before pregnancy

If you have diabetes and plan to get pregnant, doctors will have you control your blood sugar level by:

  • Following an eating plan (avoid high-sugar foods, don’t gain extra weight)

  • Exercising regularly

  • Taking insulin

During pregnancy

Your doctor may work as part of a health care team with nurses and nutritionists to lower your chance of problems. They will:

  • Try to keep your blood sugar level as close to normal as possible

  • Tell you to check your blood sugar level at home several times a day using a blood sugar meter

  • Give you insulin or other medicine to lower your blood sugar level

  • Check on your baby by counting your baby’s heart rate and doing an ultrasound

During labor and delivery

  • If you don’t go into labor by 39 weeks, doctors may start labor using medicine

  • Doctors may give you insulin through a vein during labor

After pregnancy

  • Your health care team will watch your baby closely and do blood tests often

  • If you had diabetes before pregnancy, usually you’ll be able to return to the amount of insulin or medicine you used to take within a week of having your baby

  • Gestational diabetes usually goes away after you have your baby, but you may have it again with another pregnancy, and you have a higher chance of getting diabetes permanently as you get older

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version

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