Gestational Diabetes (Diabetes in Pregnancy)

What causes gestational diabetes?

Unlike type 1 diabetes, gestational diabetes is not caused by a lack of insulin, but by other hormones produced during pregnancy that can make insulin less effective, a condition referred to as insulin resistance. Approximately 3 to 8 percent of all pregnant women in the United States are diagnosed with gestational diabetes.

Although the cause of gestational diabetes is not known, there are some theories as to why the condition occurs. The placenta supplies a growing fetus with nutrients and water, and also produces a variety of hormones to maintain the pregnancy. Some of these hormones (estrogen, cortisol and human placental lactogen) can have a blocking effect on insulin. This is called insulin resistance, which usually begins about 20 to 24 weeks into the pregnancy.

As the placenta grows, more of these hormones are produced, and insulin resistance becomes greater. Normally, the pancreas is able to make additional insulin to overcome insulin resistance, but when the production of insulin is not enough to overcome the effect of the placental hormones, gestational diabetes results.

Screening for gestational diabetes

The American Diabetes Association recommends screening for undiagnosed type 2 diabetes at the first prenatal visit for women with diabetes risk factors. In pregnant women not known to have diabetes, gestational diabetes testing should be performed at 24 to 28 weeks of gestation. In addition, women with diagnosed gestational diabetes should be screened for persistent diabetes six to 12 weeks after birth (postpartum). It also is recommended that women with a history of gestational diabetes undergo lifelong screening for the development of diabetes or prediabetes at least every three years.

Treatment for gestational diabetes

Gestational diabetes treatment focuses on keeping blood glucose levels in the normal range. Some oral diabetes medications are used during pregnancy, but many times insulin is the preferred medication. Treatment may include some or all of the following:

• Special diet
• Exercise
• Daily blood glucose monitoring
• Insulin injections
• Metformin or glyburide pills

LVHN Diabetes in Pregnancy Program

Lehigh Valley Health Network’s Diabetes in Pregnancy Program (DIPP) is unique to the region and focuses on the care and management of women diagnosed with gestational diabetes. Our Comprehensive Diabetes in Pregnancy Program (CDIPP) focuses on women with a history of diabetes and focuses on improving control prior to conception and during pregnancy. Maternal fetal medicine specialists (perinatologists), endocrinologists, nurse practitioners, nutritionists and diabetes educators work together in our program to care for women with diabetes in pregnancy and lower the chances of associated complications.