Women who are considered at risk for gestational diabetes are given a screening test called a 50 gram glucose challenge between the 24th and 28th weeks of pregnancy (those with two or more risk factors may be tested earlier). The glucose challenge is performed by giving 50 grams of a glucose drink and then drawing a blood sample one hour later and measuring the level of blood glucose present. A blood sugar level of less than 140 mg/dl at one hour is considered normal. Women with a blood sugar level greater than 140 mg/dl may have gestational diabetes, and require a follow up test called a 3-houroral glucose tolerance test (OGTT).
The OGTT requires dietary preparation. For three days prior to the test, 150 grams of carbohydrates should be consumed daily. Then a fasting period of 10 to 14 hours before the test is required; only water is allowed during this time. Because of the fasting component, the OGTT is usually performed first thing in the morning in a doctor??d by a surgical procedure called cesarean section, instead of naturally through the vagina.
If you know you want to get pregnant again, have a blood sugar test up to three months before becoming pregnant to make sure your blood sugar level is normal.
Children whose mothers had gestational diabetes are at higher risk for obesity, abnormal glucose tolerance, and diabetes.
Women who have had gestational diabetes and children whose mothers had gestational diabetes are at higher lifetime risk for obesity and type 2 diabetes. It may be possible to prevent type 2 diabetes through lifestyle changes. Talk to your health care provider about diabetes and increased risk from gestational diabetes.