Gestational diabetes is a condition that occurs during pregnancy. Like other forms of diabetes, gestational diabetes involves a defect in the way the body processes and uses sugars (glucose) in the diet. Gestational diabetes, however, has a number of characteristics that are different from other forms of diabetes.
Glucose is a form of sugar that is present in many foods, including sweets, potatoes, pasta, and breads. The body uses glucose to provide energy. It is stored in the liver, muscles, and fatty tissue. The pancreas produces a hormone (a chemical produced in one part of the body, which travels to another part of the body in order to exert its effect) called insulin. Insulin is required to allow glucose to enter the liver, muscles, and fatty tissues, thus reducing the amount of glucose in the blood. In diabetes, blood levels of glucose remain abnormally high. In many forms of diabetes, this is because the pancreas does not produce enough insulin.
In gestational diabetes, the pancreas is not at fault. Instead, the problem is in the placenta. During pregnancy, the placenta provides the baby with nourishment. It also produces a number of hormones that interfere with the body's usual response to insulin. This condition is referred to as "insulin resistance." Most pregnant women do not suffer from gestational diabetes, because the pancreas works to produce extra quantities of insulin in order to compensate for insulin resistance. However, when a woman's pancreas cannot produce enough extra insulin, blood levels of glucose stay abnormally high, and the woman is considered to have gestational diabetes.
About 1–3% of all pregnant women develop gestational diabetes. Women at risk for gestational diabetes include those who:
have a family history of diabetes
have previously given birth to a very large, heavy baby
have previously had a baby who was stillborn, or born with a birth defect
have an excess amount of amniotic fluid (the cushioning fluid within the uterus that surrounds the developing fetus)
are over 25 years of age
belong to an ethnic group known to experience higher rates of gestational diabetes (in the United States, these groups include Mexican-Americans, American Indians, African-Americans, as well as individuals from Asia, India, or the Pacific Islands)
have a previous history of gestational diabetes during a pregnancy
Rosalyn Carson-DeWitt MD, The Gale Group Inc., Gale, Detroit,