[The diagnosis of gestational diabetes]

Diabetes mellitus complicates 2 to 3 per cent of all pregnancies and 90 per cent of these women have gestational diabetes mellitus (GDM)--the most common complication seen in obstetrical practice today. It occurs in the second half of pregnancy and is usually asymptomatic. It is recommended that all pregnant women to be screened by administering a 50 g oral glucose load followed by a glucose determination 1 hour later. The test may be performed at 24 to 28 weeks' gestation in the fasting stage. A 1-hour test value of 140 mg/dl (7.8 mmol/l) or more indicates the need for a 3-hour 100 g glucose tolerance test (GTT). The patient must have a normal fasting value and two abnormal GTT glucose determinations to be designated as GDM. Early detection and management are important to prevent complications to mother and fetus. Patients with GDM represent a group at significant risk for developing glucose intolerance later in life.