Gestational diabetes is a disorder that begins or is first recognised during pregnancy.

Gestational diabetes is a carbohydrate intolerance that can become apparent around the 24th to 28th weeks of pregnancy.

Causes and Risk It's recommended that all pregnant women be screened for gestational diabetes within this time frame. In many cases, the blood glucose level returns to normal after delivery. The symptoms are usually mild and not life-threatening to the pregnant woman. However, the increased maternal glucose levels are associated with an increased rate of perinatal complications, including birth trauma, hypoglycaemia, and jaundice. Rarely, late intrauterine foetal death occurs. Maintaining control of blood glucose levels significantly reduces the risk. The risk factors for gestational diabetes are: maternal age of more than 25; a family history of diabetes; obesity; a previous delivery of an infant with a birth weight over nine pounds; an unexplained death of a previous infant or newborn; a congenital malformation in a previous child; and recurrent infections.

Symptoms

• Increased thirst
• Increased urination
• Weight loss in spite of increased appetite
• Fatigue
• Nausea
• Vomiting
• Frequent infections, including those of the bladder, vagina, and skin
• Blurred vision

Signs and Tests
An oral glucose intolerance test is given between the 24th and 28th weeks of pregnancy.

Treatment
The goals of treatment are to maintain blood glucose levels within normal limits during the duration of the pregnancy and ensure the well-being of the foetus.

Close monitoring of the mother and the foetus should continue throughout the pregnancy. Self-monitoring of glucose levels allows the woman to participate in her care. Foetal monitoring to assess the foetal size and well-being may include ultrasound exams and non-stress tests. A non-stress test is a very simple painless test for you and your baby. An electronic foetal monitor (a machine that hears and displays your baby's heartbeat) is placed on your abdomen. When a baby moves, its heart rate normally rises between 15 and 20 beats above its regular heart rate. Your health-care provider can look at the pattern of your baby's heartbeat in relationship to its movements and determine whether the baby is doing well. Your health-care provider will look for three accelerations of 15 beats per minute over the baby's normal heart rate, occurring within a 20-minute period.

Dietary management provides adequate calories and nutrients required for pregnancy and to control blood glucose levels. Patients should receive nutritional counselling from a dietician.

If dietary management does not control blood glucose levels and keep them within the recommended range, insulin therapy should be initiated. Self-monitoring of blood glucose is required for effective treatment with insulin.

Prognosis There is a slight increased risk of foetal and neonatal death with gestational diabetes, but this risk is lowered with effective treatment and surveillance of the mother and foetus. High blood glucose levels often resolve after pregnancy. However, women with gestational diabetes should be monitored postpartum and at regular intervals to detect diabetes early. Up to 30% to 40% of women with gestational diabetes develop overt diabetes mellitus within 5 to 10 years after delivery. The risk may be increased if the risk factor of obesity is present.

Complications

• Low blood glucose or illness in the newborn
• Increased incidence of newborn deaths
• Development of diabetes later in life.