Frequently Asked Questions about Gestational Diabetes

If you have been diagnosed with gestational diabetes, you probably have many questions about what this means for you and your baby. Our experts in maternal-fetal medicine and endocrinology have answered the most frequently asked questions about gestational diabetes.

What is gestational diabetes?

Gestational diabetes is a form of high blood sugar that occurs only during pregnancy. Women with gestational diabetes have normal blood sugars before pregnancy, and the large majority will have normal blood sugars immediately after they deliver. Some women have undiagnosed diabetes or prediabetes that they and their medical providers did not know they had prior to becoming pregnant. In this case, it can be difficult to determine whether the mother had been diabetic or is experiencing gestational diabetes, but treatment during pregnancy is the same: controlling blood sugars to the same goals with lifestyle changes or medication.

Pregnancy is a time when women are naturally more insulin resistant - their prepregnancy metabolism has to adjust to the nutrients required for their growing baby Gestational diabetes occurs when the pancreas, the organ that produces insulin, cannot quite make enough insulin to keep blood sugars normal during pregnancy.

What is diabetes? What is insulin? How does diabetes affect the body? Marie McDonnell, M.D., Chief of the Diabetes Section of the Division of Endocrinology, Diabetes, and Hypertension at Brigham and Women's Hospital, answers patients' most commonly searched questions about diabetes.

Will I have diabetes after I am pregnant?

No. Because it occurs only during pregnancy, gestational diabetes is not the same as pre-existing type 1 or type 2 diabetes, and the large majority of women with gestational diabetes will have normal blood sugars immediately upon delivery. However, women with gestational diabetes are at risk for developing diabetes over their lifetime and it is very important they receive ongoing diabetes screenings and preventive care. No matter what type of abnormal blood sugar you have in pregnancy, it is very important that you receive proper follow up after you deliver. Your pregnancy care team will work with you and your primary care provider to help make sure you receive the care you need.

Why does gestational diabetes happen?

The answer can be complex, but at its simplest level gestational diabetes happens when your body cannot make enough insulin to keep blood sugars normal during pregnancy.

During pregnancy, one of the placenta’s many jobs is to make sure the baby gets enough nutrients and it does this, in part, by making women more insulin resistant. Insulin is the hormone that manages nutrient metabolism in your body. Its function is to absorb glucose from your blood stream into your muscles, brain and other tissues that use it. The pancreas is the organ that makes insulin.

In gestational diabetes, the pancreas is still making insulin, but is not making quite enough to overcome the normal insulin resistance of pregnancy. In this way, the normal insulin resistance of pregnancy is like a stress-test for the pancreas.

Once women have delivered, this “stress-test” of the placenta is lifted, and for most women the pancreas is able to make enough insulin to keep blood sugars normal. However, development of gestational diabetes reflects a risk for type 2 diabetes over time, and it is critical that women with a history of gestational diabetes be followed with routine glucose screening, eat a healthy diet and get plenty of exercise to help prevent diabetes.

Read more about gestational diabetes.

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