Should all pregnant women be tested for diabetes?
Nearly all pregnant women should be tested for gestational diabetes during the 24th to 28th weeks of pregnancy. The only women who do not need to be tested are low-risk women who meetallof the following criteria:
- Under 25 years of age
- Normal body weight before pregnancy (body mass index [BMI] 18-25)
- No family history of diabetes
- Not a member of a high-risk ethnic group (such as African Americans)
Is it safe for women with diabetes to become pregnant?
In women with type 1 or type 2 diabetes who become pregnant, there is a higher risk of birth defects or death for the baby. The higher the mother's blood glucose, the greater the risk of these complications. The good news is that proper care can greatly reduce the risk of problems for the baby, so if you have diabetes and are planning to become pregnant, it is extremely important to discuss it with your doctor. Taking part in a program to understand and control your diabetes before you become pregnant can reduce the risk of your baby having major birth defects. In one study, only 1% to 2% of infants born to women who participated in such a program had birth defects compared with as many as 11% of infants whose mothers did not participate.6
What if a woman develops diabetes during pregnancy?
Gestational diabetes is when a woman who has never had diabetes develops high blood sugar during pregnancy. Hormones from the placenta (which supports the baby as it grows) can block the action of insulin in the mother's body, forcing the mother to produce up to 3 times as much insulin as normal. When the body cannot produce this extra insulin, gestational diabetes occurs and causes a buildup of sugar in the blood just like regular diabetes. Gestational diabetes occurs in about 4% of pregnancies.
Gestational diabetes can cause certain problems for the baby. The high blood sugar in the mother crosses into the baby, and since the baby is getting more energy than it needs to grow, the extra sugar is stored as fat and can lead to big babies (macrosomia) who weigh more than 4000 g to 4500 g (nearly 10 pounds) at birth. Babies with macrosomia can have shoulder injuries during birth, are at risk for breathing problems, and have a higher risk of developing obesity and type 2 diabetes later in life than babies of normal birth weight.
How is gestational diabetes treated?
Treatment for gestational diabetes aims to keep the mother's blood sugar at a normal level, and includes special meal and exercise plans and glucose testing. Some women may also need insulin injections to keep their blood sugar under control during pregnancy. For more information on treatment of gestational diabetes, including information on diet and physical activity, see the National Institute of Child Health & Human Development publication Managing Gestational Diabetes: A Patient's Guide to a Healthy Pregnancy.
For more information:
American Diabetes Association
Diabetes Public Health Resource
References
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5. American Heart Association. Heart Disease and Stroke Statistics - 2006 Update. Dallas, Texas: American Heart Association; 2006.
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9. Hu FB, Stampfer MJ, Solomon CG, et al. The impact of diabetes mellitus on mortality from all causes and coronary heart disease in women: 20 years of follow-up. Arch Intern Med. Jul 23 2001;161(14):1717-1723.
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12. Knowler WC, Barrett-Connor E, Fowler SE, et al. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. Feb 7 2002;346(6):393-403.
13. National Institute of Diabetes and Digestive and Kidney Diseases. National Diabetes Statistics fact sheet: general information and national estimates on diabetes in the United States, 2003. Bethesda, MD: U.S. Department of Health and Human Services, National Institutes of Health; 2004.
14. Heart Disease and Stroke Statistics: 2005 Update. Dallas, TX: American Heart Association; 2005.
