Gestational Diabetes

May 2004

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“Gestational” means during pregnancy. Gestational diabetes is high blood glucose that begins during pregnancy. The types of diabetes are defined by what has caused the blood glucose to be high.

If blood glucose is high, either there is not enough insulin, or the insulin is not working effectively. In gestational diabetes, something having to do with the pregnancy is causing the insulin to be ineffective, or not enough to meet the mother’s needs. Scientists don’t know what that “something” is, but it might have to do with the mother’s weight gain, or with the placenta.

Usually gestational diabetes doesn’t occur until later in pregnancy, after the first three months. The baby is growing very quickly. The body has already formed, so birth defects are not common.

It is important to control gestational diabetes and keep the mother’s blood glucose near normal. If the mother’s blood glucose stays high, some of the glucose will “spill” over to the baby. With extra glucose for energy, the baby will grow very large and weigh more than is healthy. It may be difficult to give birth to such a large baby and a Caesarian section, or “C section” may be needed.

Heavier babies often have more difficulty breathing, and are more likely to develop obesity or diabetes as they grow up.

After birth, gestational diabetes usually goes away and the mother’s blood glucose will be normal without any treatment. During pregnancy, the mother will have to follow a meal plan, and usually will need insulin injections.

Remember, this information doesn’t replace any that your doctor may have given you or spoken to you about. Whenever you have questions about your diabetes or how it is being treated, talk to your doctor.