Gestational Diabetes

Gestational Diabetes

Pregnant women who have never had diabetes before but who have high blood sugar (glucose) levels during pregnancy are said to have gestational diabetes. Gestational diabetes is a form of diabetes that some women develop during the 24th – 28th week of their pregnancy. It usually disappears after the birth and does not mean that the baby will be born with diabetes.

Diabetes Mellitus is a condition when the pancreas (the organ responsible for producing insulin) is either unable to make insulin, or the insulin is unable to work effectively. The function of insulin is to keep the glucose levels within normal limits. With inadequate insulin, glucose builds up in the blood leading to high blood glucose levels causing health problems.


The definite cause of Gestational diabetes is not known, but it is assumed that as pregnancy progresses, the mother’s energy needs increase. Also, placental hormones that help the baby grow and develop, block the action of the mother’s insulin. This is called insulin resistance. The pregnant woman needs extra insulin so the glucose can get from the blood into the cells where it is used for energy. If the body is unable to meet this requirement, then diabetes develops. When the pregnancy is over and the insulin needs return to normal, the diabetes usually disappears.

Women who develop gestational diabetes have a greater risk of developing Type II diabetes later on.


Diabetes often has no symptoms, which is why all pregnant women are routinely tested.

If symptoms occur, they may include:

  • Unusual thirst
  • Excessive hunger
  • Excessive urination
  • Frequent infections
  • High blood pressure

Risk factors

Any pregnant woman can develop gestational diabetes, but risk factors that increase susceptibility include:

  • Being overweight
  • A family history of diabetes
  • Women with hypertension (high blood pressure)
  • Being over the age of 30 years (everyone’s tendency to develop diabetes increases with age)
  • Previous babies were large at birth (8 pounds and over)

Tell your doctor:

  • If you have had gestational diabetes in a previous pregnancy
  • If you have a family history of gestational diabetes or diabetes
  • If you have given birth to a baby weighing 8 pounds or over

Course of Illness

Although gestational diabetes usually goes away after the birth (when hormone levels return to normal), it still needs to be taken seriously.

The main concern is that it can increase the baby’s weight, and have other health effects on the unborn baby. If the baby becomes very large it may be necessary for the woman to have a Caesarean delivery. Women who develop gestational diabetes have about a 50% risk of developing Type II diabetes later on. Type II Diabetes, which is increasingly common in people over the age of 40, is a chronic disease, which has to be carefully managed with healthy eating and regular physical activity. Sometimes long-term medication is also needed. If Type II diabetes isn’t controlled it can cause serious health problems including heart and kidney disease, and eye problems.

Routine Tests

Pregnant women are routinely checked for gestational diabetes between the 24th and 28th weeks of their pregnancy. Women at increased risk are usually tested earlier. The glucose challenge test involves taking a glucose drink, waiting for one hour and then having a blood test. If your glucose level is high, you will have additional glucose tolerance test to confirm the diagnosis. This involves fasting the night before the test, drinking a stronger glucose solution, and being blood tested each hour for 3 hours.

Managing Gestational Diabetes

A woman with gestational diabetes needs careful monitoring for the remainder of her pregnancy.
Management is mainly aimed at changing to a healthy eating plan, increasing physical activity, and monitoring blood glucose levels. Specific management strategies include:

  • Eating regular meals. Hospital dietitians can advise on which foods to eat and which foods to avoid, and how often to eat
  • Regular exercise to help reduce insulin resistance
  • Dietary modifications, such as switching to a low fat, high fiber diet with plenty of fresh foods
  • No alcohol or cigarettes
  • Regular blood tests performed at home to check glucose levels
  • Some women may need to take medications, these may include tablets to insulin injections