Gestational diabetes is a disorder of glucose (sugar) metabolism due to a relative lack of insulin which is diagnosed for the 1st time during pregnancy. This condition is common in our community with an incidence of 8 – 10% and appears to be rising due to dietary habits and lifestyle patterns. It does not refer to patients with pre-existing diabetes who become pregnant. All patients during pregnancy should be screened for gestational diabetes and this is done through the glucose challenge test (GCT) which involves the administration of a 75 gram sugar drink in the non-fasting state with a blood glucose estimation taken 1 hour later. This test can be done in the 3rd trimester or preferably earlier in pregnancy to identify the patient at increased risk for definitive testing at 28 weeks gestation by the glucose tolerance test (GTT). The GTT is a 2 hour test performed after an overnight fast and enables the diagnosis of gestational diabetes to be made.
Treatment of gestational diabetes requires at least twice daily testing of blood sugar levels 2 hours after breakfast, lunch or dinner with good control being a blood glucose level of < 7.0 mmol/L. A glucometer such as the Freestyle Lite should be purchased and you will be instructed on how to use it. Dietary restriction with avoidance of refined carbohydrates such as chocolates, soft drinks and cakes is essential with a reduced intake of complex carbohydrates of bread, pasta and rice. In those patients in whom optimal control cannot be maintained with diet alone, treatment with insulin injections will be required and this may be once, twice or 4 times daily injections. Good control of the diabetes ensures normal foetal growth in utero and improves the chances of a normal delivery at term.