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Diabetes in Pregnancy

Gestational diabetes refers to diabetes that is diagnosed during pregnancy. Gestational diabetes occurs in about 7 percent of all pregnancies, usually in the second half of the pregnancy. It almost always goes away as soon as your baby is born. However, if gestational diabetes is not treated during your pregnancy, you may experience some complications.

Causes

Pregnancy hormones cause the body to be resistant to the action of insulin, a hormone made by your pancreas that helps your body use the fuels supplied by food.

The carbohydrates you eat provide your body with a fuel called glucose, the sugar in the blood that nourishes your brain, heart, tissues and muscles. Glucose also is an important fuel for your developing baby. When gestational diabetes occurs, insulin fails to effectively move glucose into the cells that need it. As a result, glucose accumulates in the blood, causing blood sugar levels rise.

Diagnosis

Gestational diabetes is diagnosed with a blood test. Your blood glucose level is measured after you drink a sweet beverage. If your blood sugar is too high, you have gestational diabetes. Sometimes one test is all that is needed to make a definitive diagnosis. More often, an initial screening test is given and, if needed, a longer evaluation is performed.

Gestational diabetes usually does not occur until later in pregnancy, when the placenta is producing more of the hormones that interfere with the mother's insulin. Screening for gestational diabetes usually takes place between weeks 24 to 28. However, women at high risk are usually screened during the first trimester.

Risk Factors

There are a number of risk factors associated with gestational diabetes, including:

  • Being overweight
  • Giving birth to a baby that weighed more than 9 pounds
  • Having a parent or sibling with diabetes
  • Having had gestational diabetes in the past
  • Having glucose in your urine

In addition, gestational diabetes occurs more often in African Americans, Native Americans, Latinas and women with a family history of diabetes.

Gestational Diabetes and Your Baby

Gestational diabetes can impact your developing baby in a couple of ways:

  • High Birth Weight — Exposure to higher sugar levels from the maternal bloodstream can result in a larger baby and a high birth weight. The baby's pancreas produces extra insulin in response to the higher glucose, which results in the baby storing extra fat and growing larger. A larger baby can make delivery more complicated for both mother and baby.
  • Low Blood Sugar — If your blood sugar has been elevated during the pregnancy, your baby may have low blood sugar, called hypoglycemia, shortly after birth. The extra insulin that your baby produces when your blood sugar is high continues to bring your baby's blood sugar down for a short time after birth. Without the continued supply of sugar from maternal blood, your baby's blood sugar level may fall too low.

    However, this is temporary and the nurses and doctors caring for your newborn will monitor your baby carefully and treat any episodes of low blood sugar that may occur.

Avoiding Complications

Remember that the complications of gestational diabetes can be prevented by keeping your blood sugar under control during your pregnancy. The goal of treatment is to keep your blood sugar in the normal range. Most women with well-controlled blood sugar deliver healthy babies without any complications.

Treatment

Diet

The first step in treating gestational diabetes is to modify your diet to help keep your blood sugar level in the normal range. You should meet with a registered dietitian to develop a customized eating plan to help you mange your blood sugar. You may also wish to read Dietary Recommendations for Gestational Diabetes.

The main principles for diet include:

  • Avoid high-sugar foods. For the remainder of your pregnancy you should avoid desserts, sweets, candy, cookies, soft drinks and fruit juice. You should eat fruit, but since fruit is high in natural sugar, limit fruit to one small serving at a time.
  • Eat reasonable portions of high-carbohydrate foods. Carbohydrates are found in breads, cereals, rice, pasta, potatoes, beans, fruits, milk, yogurt and some vegetables. Carbohydrate foods break down into glucose during digestion. They are important because they contain nutrients that are necessary for both you and your developing baby. Therefore, it is important to eat carbohydrate foods at each meal, but don't over-eat.
  • Eat smaller, more frequent meals. Space out the carbohydrate foods you consume throughout the day. Cutting down the portion of carbohydrate foods eaten at one sitting means that you need to eat more often to meet your pregnancy nutrient needs. Eating three smaller meals and three or four snacks between meals can help you meet your pregnancy diet goals without elevating your blood sugar.

Blood Sugar Monitoring

The only way to know that your gestational diabetes is being properly controlled is to check your blood sugar frequently. You will be instructed on the use of a home blood sugar monitor. You should check your blood sugar at least four times daily, or as directed by your doctor. Check your fasting blood sugar first thing in the morning, before you have had anything to eat or drink. Also check your blood sugar one hour after starting to eat your three main meals: breakfast, lunch and dinner. Check with your doctor for target blood sugar levels.

Other Treatments

The majority of women with gestational diabetes will be able to control their blood sugar simply by modifying their diet. You will need to follow the diet guidelines until your baby is born. After delivery, most women are able to resume their normal eating habits. Gestational diabetes does not interfere with your ability to breastfeed your baby.

For about 30 percent of the women who develop gestational diabetes, following a diet is not enough to control their blood sugar. For these women, insulin therapy is usually initiated. Using insulin is safe during pregnancy. Women who take insulin still need to continue with the prescribed diet and monitor their blood sugar levels.

After Delivery

After your baby is born, your blood sugar will be checked to make sure it is normal. Fortunately, gestational diabetes almost always goes away after your baby is born. If your blood sugar does not return to normal, it may mean that you had diabetes before you became pregnant.

The most important thing to remember is to check your blood sugar before you become pregnant again. Women who had gestational diabetes have an increased risk of developing type 2 diabetes. Women who had diabetes before they become pregnant have an increased risk of pregnancy complications. Elevated maternal blood sugar during the first 12 weeks of pregnancy, when the major organ systems are developing, increases risks to the fetus. Women with diabetes can help improve their chances of having a healthy baby by normalizing their blood sugar before becoming pregnant.

 

Reviewed by health care specialists at UCSF Medical Center.

This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.

Related Information

UCSF Clinics & Centers

Women's Health Center

Obstetrics and Gynecology Services at Mount Zion
2356 Sutter St.
San Francisco, CA 94143
Obstetrics: (415) 353-2566
Gynecology: (415) 885-7788
Obstetrics Fax: (415) 353-2496
Gynecology Fax: (415) 353-9550

Obstetrics Services at Parnassus
400 Parnassus Ave., Floor B1, Suite A-096
San Francisco, CA 94143
Phone: (415) 353-2566
Fax: (415) 353-2496

Obstetrics & Gynecology Services at Serramonte
333 Gellert Blvd., Suite 120
Daly City, CA 94015
Gynecology: (415) 885-7788
Obstetrics: (415) 353-2566
Fax: (650) 991-2748

How to Reach Us

For more information or to request an appointment with a registered dietitian, please contact:
Nutrition Counseling Center.
Phone (415) 353-2291

Condition Information