Gestational diabetes

Definition
Diabetes is a condition in which glucose (a blood sugar that supplies the body with energy) cannot work properly because of a problem with insulin production or use in the body. Insulin is a hormone produced by the pancreas to regulate blood glucose levels. It works like a key that opens the cells in our bodies to accept glucose, thus providing us with energy.
Gestational diabetes is the development of glucose intolerance during pregnancy in women who did not have diabetes before. It occurs because the placenta produces hormones that interfere with insulin's ability to move glucose into cells (known as insulin resistance). If your pancreas is not able to produce enough insulin to overcome the effect of the increased hormones, glucose levels in your blood will rise and gestational diabetes will develop. Gestational diabetes is the most common complication of pregnancy, affecting about 4 percent of all pregnant women. It poses potential risks to both mother and baby.


Causes/associated factors
During pregnancy, the placenta (the structure in the womb that nourishes the fetus and helps it discard waste) releases hormones such as estrogen, cortisol and human placental lactogen. These hormones can partially block the effect of insulin, making it less effective in transporting glucose into your cells. This can result in gestational diabetes -- an excessive amount of glucose in your blood and not enough in your cells for energy. Gestational diabetes typically begins near the 20th to 24th week of pregnancy.
Gestational diabetes poses risks to both mother and baby, which may include:

preeclampsia (a serious condition that causes elevated blood pressure, as well as protein in the urine; preeclampsia can affect fetal growth or cause fetal death if not treated promptly)
polyhydramnios (excessive amniotic fluid, the fluid that protects the fetus in the womb)
macrosomia (a larger than normal baby, which can complicate delivery and increase the risk of birth injuries or necessitate a cesarean delivery, surgical delivery through the mother's abdomen)
respiratory distress syndrome (a condition that can affect a baby's breathing, especially if the baby is premature and the lungs have not fully developed)
stillbirth late in the pregnancy
Factors that may increase the risk of gestational diabetes include:

obesity (defined as 20 percent or more over desired body weight)
age (The risk is higher for women age 25 and older.)
family history of diabetes in first-degree relatives
previous unexplained stillbirth
a very large fetus
frequent miscarriages
previous history of gestational diabetes or glucosuria (glucose in the urine)
a large amount of amniotic fluid
a fetus with birth defects

Signs/symptoms
Although symptoms of gestational diabetes may be absent, they may include:
increased thirst
frequent urination
weight loss despite an increase in appetite
extreme fatigue and lack of energy
nausea and vomiting
vaginitis (an inflammation of the vaginal tissue)
slow-healing skin infections
frequent bladder infections
blurred vision

Diagnosis
Routine gestational diabetes screening is generally recommended for all pregnant women because many women affected do not have associated risk factors. The initial screening is usually done between 24 and 28 weeks of pregnancy or sooner if you have a history of gestational diabetes with a previous pregnancy or other risk factors as listed above.
Screening between 24 and 28 weeks of pregnancy is very important for women who are members of an ethnic/racial group with a high prevalence of diabetes, including Hispanic Americans, Native Americans, Asian Americans, African Americans and Pacific Islanders.

The most common screening test is the 50-gram glucose screening test, also called the glucose challenge test. This test is typically done between the 24th and 28th week of pregnancy. (Earlier screening may be done if you have risk factors for the condition, but the test is repeated at 24 to 28 weeks even if initial results are normal.) For the screening, you simply drink 50 grams of a glucose solution and a blood sample is taken one hour later. You don't have to fast for this test. If the result is normal, you probably won't need further testing unless you develop symptoms of gestational diabetes.

If the result is abnormal, you'll need a three-hour glucose tolerance test. This test requires some fasting. Your blood will be drawn, and then you'll drink 100 grams of a glucose solution. Your blood will be drawn again 30 minutes, one hour, two hours and three hours later. Gestational diabetes is diagnosed if two or more of these blood samples are abnormal.

After the diagnosis
Once gestational diabetes is diagnosed, the doctor will closely monitor your pregnancy. Screening tests and ultrasound exams (using sound waves to create an image of internal body parts) throughout the pregnancy can help monitor the baby's growth and well-being. The American College of Obstetrics and Gynecology recommends specific tests early in the pregnancy to detect neural tube defects (affecting the brain and spinal cord), including blood testing at 16 to 20 weeks and ultrasound at 18 to 20 weeks.

Depending on the circumstances, the doctor may recommend a nonstress test (a diagnostic test that helps doctors determine the response of a fetal heartbeat to fetal movement, spontaneous contractions or other stimuli), contraction stress test (a procedure that tests the condition of the fetus by stimulating the uterus to contract) and/or other tests during the third trimester.

A blood test called hemoglobin A1C (HgbA1C) will be done each month or so and can help the doctor determine how well controlled your blood sugar has been in the months just prior to the test. The goal for this test is a result less than 7 percent, with 4 to 6 percent considered optimal. Your doctor will consider a change in your treatment plan if the result is higher than 8 percent.

For your health, as well as your baby's, it's important to keep all regularly scheduled medical appointments throughout your pregnancy.


Treatment
To control the condition, it's important to learn as much as you can about gestational diabetes. Your doctor will design a unique treatment plan to follow throughout your pregnancy.
Diet
Dietary counseling is an important part of your treatment plan. Your doctor will prescribe a diet that helps control the diabetes while meeting your nutritional needs, as well as your baby's. You may be referred to a dietitian for specific dietary instruction. The American Diabetes Association offers a booklet titled, "Exchange Lists for Meal Planning" to help you learn how to use exchanges. You can find it on their Web site (www.diabetes.org) or request a copy by calling (800) 342-2383.

Until you can meet with a dietitian, keep these general food suggestions in mind:

Breads and grains (6 to 11 servings per day): 1 slice bread, half a bagel or English muffin, 1 plain rice cake, 6 crackers (such as rye crisps or saltines), 3 graham crackers, ¾ cup ready-to-eat cereal, ½ cup pasta or rice, ½ cup corn, small plain baked potato, small pancake or 6-inch tortilla

Fruits (2 to 4 servings per day): 1 piece fresh fruit, 1 melon wedge or ½ cup chopped, cooked, frozen or unsweetened canned fruit

Vegetables (3 to 5 or more servings per day): ½ cup cooked or canned vegetables, or 1 cup chopped, uncooked or frozen vegetables

Dairy (4 servings per day): 1 cup low-fat milk, 1 cup soy milk, 1 cup low-fat unsweetened yogurt, 1½ ounces cheese or ½ cup low-fat cottage cheese

Meat and poultry (2 to 3 servings per day): 2 ounces cooked lean meat or poultry; 2 ounces cheese; 2 eggs or equivalent egg substitute; 1 cup cooked dried beans or peas; 2 tablespoons peanut butter; or ¼ cup tofu

Fats and oils (approximately 5 to 8 teaspoons per day): vegetable oil (such as olive, canola or peanut oil), tub margarine, and fat-free or low-fat salad dressing

Sweets and snacks (in limited amounts): peanut butter and crackers, cheese and crackers, vanilla wafers, plain popcorn and pretzels

"Free" foods: raw vegetables, diet soda, sugar-free gelatin, sugar-free syrup, low-sugar jelly, sugar-free candy and gum, and unsweetened frozen fruit pops
Exercise
Exercise can help you control glucose levels, as well as stay healthy during pregnancy and avoid excessive weight gain. Discuss your current exercise habits and plans with your doctor. Women who are already physically active can often continue with a fitness program approved for pregnancy. If you're not physically active, begin exercising slowly, and gradually increase the intensity according to your doctor's instructions.

Blood glucose and other self-monitoring
You will learn to do regular blood glucose testing at home with a home glucose monitor. Your doctor may recommend testing as often as four times a day, often as soon as you get up, and then one to two hours after every meal. It's important to keep fasting blood sugars less than 90, and two-hour postprandial (following a meal) blood sugars less than 120. You may also be asked to check a urine ketone (the end product of fat metabolism) each morning. The result should be negative.

Insulin
You may need to take insulin if your diet and exercise routine do not keep your blood glucose at a normal level. (Insulin is safe to take during pregnancy because it doesn't cross the placenta.) Your doctor will determine the proper dosage, and you'll learn about any adjustments that may be necessary depending on your blood glucose level at a given moment. Unless your blood sugar is kept in excellent control, you may face a higher risk of complications that affect the baby. Insulin after pregnancy is usually unnecessary.

Because your diet, insulin and exercise plan can all affect your blood glucose level, do not make any changes without consulting your doctor.

If you take insulin and have morning sickness, make sure you know the symptoms of low blood sugar, such as shakiness, dizziness, sweating, irritability, hunger, and heart palpitations or rapid heartbeat. If you experience any of these symptoms, try one of the following: ½ cup orange juice, 1/3 cup apple juice, ¼ to 1/3 cup raisins, 4 to 6 ounces regular soda, or 1 tablespoon corn syrup or honey.

Prenatal visits
Throughout your pregnancy, your doctor will see you often to monitor your blood glucose levels and the growth and well-being of your baby. If you develop complications, an early or cesarean delivery may be needed. (Women with diet-controlled gestational diabetes don't often require early delivery.)

After delivery
Your baby will be closely monitored for low blood sugar levels, jaundice (yellowing of the skin and whites of the eyes) and other possible health problems. When gestational diabetes is well controlled, the mother's blood sugar often returns to normal after delivery.


Complications
Early complications
Hypoglycemia (low blood sugar) is a common condition during the early weeks of pregnancy, but it's also related to insulin treatment of gestational diabetes. Because hypoglycemia can occur with little warning, it's important for you, your family members and others to be aware of the condition. Mild symptoms may include:

shakiness
dizziness
sweating
irritability
hunger
heart palpitations or rapid heartbeat
Moderate to severe symptoms may include:

headache
difficulty concentrating or confusion
poor coordination
unusual behavior patterns such as stubbornness or uncooperativeness (may resemble a state of intoxication)
eventually, stupor or unconsciousness
To prevent hypoglycemia, don't miss or delay meals. To treat a hypoglycemic episode, eat something sweet right away. It's a good idea to carry something sweet with you at all times in case of a hypoglycemic episode. Examples include ¼ to 1/3 cup raisins or 1/3 to ½ tube (30 grams) of glucose in gel form, such as InstaGel or MonGel.

Later complications
After one bout with gestational diabetes, you'll have an increased risk of developing the condition with future pregnancies. One study indicated that it may recur in as many as 60 percent of women who become pregnant again and that recurrence is more common in obese women. Also, more than 50 percent of women who have gestational diabetes develop type 2 diabetes (non-insulin-dependent diabetes) within 20 years. Ask your doctor about postpartum screening for diabetes, as well as a follow-up testing schedule.

Unless your blood sugar is well controlled, your child may be at increased risk for obesity during childhood and possibly into adulthood, as well as developing glucose intolerance or diabetes.


Prevention
Before conception, it's a good idea to discuss prepregnancy planning with your doctor. If you're overweight or obese, your doctor may recommend losing weight before trying to get pregnant. It's also helpful to maintain your ideal weight before and after pregnancy. Follow your doctor's suggestions for a healthful diet. Finally, tell your doctor if you have any risk factors for gestational diabetes.