Overview, Causes, & Risk Factors
Gestational diabetes is an intolerance to glucose that first occurs, or isfirst detected, during pregnancy.Glucose is the main form of sugar in the body. Gestational diabetes occurs in4% of all pregnancies.
What is going on in the body?
Glucose is an important source of energy used by the body’s cells. When aperson eats, the pancreas normally makes extra insulin. The insulin causes theglucose in the blood to move inside the body’s cells. In a woman withgestational diabetes, the hormones produced in pregnancy block the effects of insulin. Glucose then builds upinthe blood and the cells are left without a main source of energy. The result isa high level of glucose in the blood, a condition known as hyperglycemia. Highblood sugar levels can damage the growth of the fetus. This may cause complicationsfor both the mother and baby.
What are the causes and risks of the disease?
The following conditions may increase a woman’s chance of developinggestational diabetes:
- age over 25 years
- family history of diabetesmellitus, including type 1diabetesmellitus or type 2 diabetesmellitus in a sibling or parent
- personal history of gestational diabetes
- marked obesity
- previous delivery of an infant with a birth weight of more than 9 pounds
- a previous stillbirth
- previous delivery of a child with birth defects
- recurrent or persistent bladderinfections or Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis
- glucose in the urine sample taken in the healthcare provider’soffice
- being a member of an ethnic group with a high incidence of gestationaldiabetes. This includes women of Latino, African American, Native American,Asian, or Pacific Islands descent.
Symptoms & Signs
What are the signs and symptoms of the disease?
Usually there are no symptoms of gestational diabetes. If symptoms develop, theyare often mild and may include:
- excessive thirst
- excessive weight gain or sometimes excessive weight loss despite increased appetite
- increased urination
- recurrent Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis.
- blurred vision
- recurrent or persistent bladder infections or bacteria inthe urine
Diagnosis & Tests
How is the disease diagnosed?
The American Diabetes Association (ADA) recommends glucose testing of womenwith any of the risk factors listed above as soon as feasible during pregnancy.If gestational diabetes is not diagnosed during the initial screening of highrisk women, they should be retested between 24 and 28 weeks of pregnancy.Similarly, women of average risk should be tested between 24 and 28 weeks ofpregnancy.
The ADA describes 2 approaches to evaluation of gestational diabetes inpregnant women:
- The one-step approach is done with an oral glucose tolerance test. The woman drinks a liquid containing 50grams of glucose and the blood glucose level is measured an hour later.
- The two-step approach starts with the same oral glucose tolerance test as the one-step approach. If thewoman’s blood glucose is elevated on the first test, a diagnostic oral glucosetolerance test is done. The woman drinks a liquid containing 100 grams ofglucose, and the blood glucose level is measured 1, 2, and 3 hours later.
If the blood glucose level is elevated in either of the approaches, adiagnosis of gestational diabetes is made.
Prevention & Expectations
What can be done to prevent the disease?
Gestational diabetes can sometimes be prevented by regular exercise and abalanced diet to maintain a healthy weight before conceiving and during pregnancy. It is important to let thehealthcare provider know if there is a family history of diabetes.
What are the long-term effects of the disease?
Complications for the mother include:
- bacteria in the urine, with chronic bladder infections
- chronic Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis
- higher risk of preeclampsia, or very high blood pressure
- swelling in the arms andlegsas a result of fluid buildup
- carpal tunnel syndrome, or pain and numbness involving the hand and arm
- premature labor
- increased need for medication to induce labor
- increased risk of forceps delivery or cesarean section
What are the risks to others?
Complications for the baby include:
- macrosomia, which means having a large body
- polyhydramnios, or excessive amniotic fluid
- increased incidence of birth defects
- premature delivery
- increased risk of miscarriage
- hypoglycemia, or low bloodsugar levels at birth
- hypocalcemia, or low calcium levels at birth
- polycythemia, or too many red blood cells at birth
- respiratory problems, including respiratory distresssyndrome
- cardiomyopathy, or damaged heart tissue
- congestive heart failure
- increased risk of birth trauma such as shoulder dystocia, which occurswhen the baby’s shoulder gets stuck during delivery
- decreased ability of the baby to tolerate labor
Treatment & Monitoring
What are the treatments for the disease?
The goal of treatment is to bring blood glucose levels to normal, and to keepthem there throughout the pregnancy. This will prevent complications for bothmother and child. The diet should provide enough calories and nutrients toallow appropriate weight gain in both mother and fetus. A dietician willprovide counseling and education. If changing the diet does not control glucoselevels, insulin injections may be needed.
Until recently, oral medications were not recommended for gestational diabetes.However, a recent study indicated that glyburide is safe and effective to takein the last 6 months of pregnancy.
What are the side effects of the treatments?
Hypoglycemia, or low blood sugar, may result if toomuch insulin is given, or if meals are skipped. Hypoglycemia should be avoided,because the fetus will also experience low blood sugar levels.
What happens after treatment for the disease?
Pregnancy hormones drop dramatically after delivery, and a woman may no longerneed insulin. High blood glucose levels usually go away after pregnancy. But 30%to 40% of women with gestational diabetes may develop type 2 diabetes at some time in their lives. Obesity or a family history of diabetesmayincrease this risk. A balanced diet and exercise after delivery will help withweight loss and will lower the risk ofdiabetes in the future. At the exam 6 weeks after delivery, a oral glucose tolerance test can helpdetermineif further treatment is needed.
How is the disease monitored?
Women with gestational diabetes run a high risk of having it in futurepregnancies. Women who previously had gestational diabetes but are not pregnant shouldhave fasting blood sugar testseachyear to detect diabetes.
Article type: xmedgeneral