How To Prepare For The Gestational Diabetes Test
Most pregnant Mamas loathe ‘the diabetes test’. No one in their right mind enjoys fasting before smashing 75gm of glucose. BUT, unfortunately the Glucose Tolerance Test (GTT) is here to stay. Unless some genius comes up with a fool-proof cure for Gestational Diabetes.
So we’ve laid out exactly what you need to do to make the test not only easier, but also more likely to be successful, ie not have to be repeated.
What Is The Glucose Tolerance Test?
At around 28 weeks pregnant, women who consent are screened for gestational diabetes mellitus aka ‘GDM’ by completing the GTT test. If you happen to have any history or complexities that would put you at increased likelihood of having GDM, you will be offered this test earlier in the first trimester, and again at 28 weeks.
The GTT has several steps. First, you have to fast overnight, then your fasting blood glucose is tested by blood test, you then will be given the GTT drink and asked to sit and wait to have your blood glucose tested again at one hour and two hours post drink.
The drink itself comes in many variations – green, clear, orange… it just depends on what is stocked where you get your GTT done. But they are all the same test – 75 grams of glucose. I thought mine tasted like fizzy lime cordial, some Mamas say it’s more like flat lemonade.
The test is looking at how your body responds to a high glucose load. The test will be negative if all three blood glucose tests (fasting, 1 hour, 2 hours) are within normal range. If any one of these tests are elevated, GDM is diagnosed.
So What Is Gestational Diabetes?
GDM is diabetes of pregnancy. That means once you have birthed, you are no longer considered diabetic. That being said, history of GDM is linked to higher risk of Type 2 diabetes later in life, so it is important to have diabetes follow-up with your GP at 6-8 weeks post birth and ongoing.
The hormones produced by the placenta are vital in helping a baby grow and develop. However, these hormones also block the action of insulin, which lowers blood glucose levels.
In pregnancy, the need for insulin is 2-3 times higher because of this insulin resistance. In the case of GDM, the body isn’t coping with the extra demand for insulin and the blood glucose levels are therefore higher.
Why Is Gestational Diabetes An Issue?
Poorly controlled GDM increases the risk fo having a large baby, pregnancy and birth complications, induction or other interventions of labour, caesarean section, unstable blood sugars of baby, and poorer outcomes for Mum and baby.
If blood glucose levels are well controlled with diet and lifestyle changes or good medication management, the risks of GDM can be minimised.
How To Prepare For The GTT (For Best Results)
Don’t do excessive exercise: It won’t give you better test results. In fact, it will do the opposite. Exercise demands more glucose to supply energy to your muscles. When you have limited insulin available, like in pregnancy, your blood glucose level can actually increase with exercise.
Don’t fast for more than 10 hours: Fast overnight (for at least 8 hours) and have your GTT first thing in the morning. It’s best to have a high protein late snack, because if you fast for more than 10 hours you can have a ‘false spike’ of your blood glucose level due to the hormone glucagon being released.
Don’t – smoke, chew gum, exercise or eat or drink anything other than unflavoured water during the fasting period.
Don’t – exercise, walk around, vomit (if possible!), or eat or drink during the test either. Sips of water are ok.
What you should do – Book your GTT appointment at pathology prior to the day to prevent fasting and not being able to complete the test due to business.
– Tell the pathology staff if you haven’t fasted appropriately or if you have been sick during the test as this will affect your test results.
– Take a book or magazine with you so you can rest for the two hours you have to wait… or even jump on The Empowered Mama Project website and get informed about all things pregnancy, birth and motherhood!