What to expect from a one-hour glucose test

During pregnancy, hormones can make insulin less effective. The test measures blood glucose after a measured glucose drink to identify people who may need a diagnostic assessment for gestational diabetes. A screening result above the clinic's threshold is not, by itself, a diagnosis.

The one-hour test is not the same protocol in every service. Some clinics use it as an initial screen without fasting, while others use a fasting oral glucose tolerance test with different blood-draw times. Your appointment instructions take priority because preparation and interpretation depend on the exact protocol.

Confirm whether you should fast and whether usual medicines can be taken. Tell the clinic if you are unwell or have had bariatric surgery, because this can affect which test is suitable. Once you drink the solution, follow instructions about eating, drinking, smoking and activity until the timed blood sample is collected.

The drink may cause nausea, light-headedness or a warm feeling. Tell staff promptly if you vomit, as the result may not be usable and the test may need a different plan. Afterward, eat and drink according to the clinic's advice, then wait for the service to explain the result and any follow-up.

Contact the clinic if you cannot keep the drink down, accidentally eat during a required fast, miss the timed blood draw or do not receive the result within the timeframe they gave you. Seek urgent help for severe breathing difficulty, facial or throat swelling, collapse, or another intense reaction during or after the drink.

Check whether this is a screening or diagnostic test, whether fasting is required, which medicines to take that morning, when results will be available, and what follow-up test or care would be offered if the glucose value is above the local threshold.