Do you need a referral for glucose tolerance test?

An obstetrician, midwife, family doctor, or maternity clinic may request the test and send an order to the laboratory. Some laboratories accept a direct booking, but others require a clinician's request and instructions about preparation.

The glucose tolerance test measures how your blood glucose changes after you drink a glucose solution. Blood samples are taken according to the laboratory's protocol, which may mean attending while fasting and remaining at the laboratory during the test.

Pregnancy can change how the body responds to insulin. Your maternity clinician may recommend testing because of your pregnancy history, medical factors, symptoms, or routine antenatal care. A result outside the laboratory's pregnancy range does not by itself explain how you feel; your clinician will interpret it with your overall care and discuss next steps.

Ask your maternity provider whether they have already issued a laboratory request. Confirm the laboratory location, whether fasting is required, how long the visit may take, and whether you should bring a referral or pregnancy documents. Follow the preparation instructions you receive rather than changing meals or medicines on your own.

If you have nausea, feel faint when fasting, or cannot keep fluids down, tell the ordering clinician before the appointment. The team may advise a different arrangement or tell you how to safely complete the test.

Seek prompt medical advice if you have severe vomiting, confusion, fainting, marked weakness, or symptoms that feel sudden or severe. During pregnancy, contact your maternity team urgently for vaginal bleeding, leaking fluid, severe abdominal pain, or reduced fetal movements.

Do not wait for a routine test booking if you feel acutely unwell. Tell the service that you are pregnant and describe your symptoms so you can be directed to the appropriate care.

Ask: Why do I need this test? Has the laboratory request been sent? Must I fast, and may I drink water? Should I take my usual medicines? How long will I be there? When will the result be reviewed, and who will contact me?