The glucose test and gestational diabetes, in plain words
Been offered a glucose test? Here is what it is for, what usually happens on the day, and what it means if you are told you have gestational diabetes.
By PreggieLover 4 min read
At one of your appointments your midwife might say, We would like to offer you a glucose test. If your first thought is, Have I done something wrong?, the answer is no. Here is a plain-words guide to what this test is, why it is offered and what happens next.
What is gestational diabetes?
During pregnancy, hormones from the placenta make it harder for your body to use insulin, the hormone that keeps blood sugar levels steady. Most women's bodies make enough extra insulin to cope. In some women they cannot, and blood sugar rises. This is called gestational diabetes. It usually develops in the second half of pregnancy and in most cases goes away after the baby is born.
It is important to find it because high blood sugar in pregnancy can affect the baby's growth and the birth. The good news is that when it is found and managed, most women go on to have healthy pregnancies and babies.
Who is offered the test?
This depends on where you live. Some countries offer a glucose test to every pregnant woman. Others, including the UK, usually offer it to women with certain risk factors, such as:
- a higher body weight
- gestational diabetes in a previous pregnancy
- a previous baby who was large
- a parent, brother or sister with diabetes
- a family background that carries a higher risk, which includes Black African, African Caribbean, South Asian and some other ethnic groups
Your midwife may also suggest a test if sugar shows up in your urine more than once.
When is it done?
Many clinics offer it somewhere around 24 to 28 weeks. If you have had gestational diabetes before, you may be offered testing earlier as well.
What happens on the day?
The most common test is the oral glucose tolerance test, often shortened to OGTT. Procedures vary, but it often goes like this:
- You do not eat for a number of hours beforehand, usually overnight. Your clinic will tell you exactly what you may drink.
- A blood sample is taken.
- You drink a sweet glucose drink.
- You wait, usually for around two hours, resting quietly, and then another blood sample is taken.
Some clinics use a slightly different version. Follow the instructions in your letter and ask if anything is unclear.
Tips for test day
- Take a book, a downloaded film or your Bible to pass the time.
- Bring a snack and a drink for afterwards.
- If you are on medication or have diabetes already, ask your doctor in advance how to prepare. Do not change any medicines on your own.
- If you feel very unwell after the drink, tell the staff.
If the result shows gestational diabetes
It is natural to feel shocked or even guilty. Please do not. Gestational diabetes is caused largely by pregnancy hormones and is not a judgement on you. You will usually be referred to a specialist team, who may help you to:
- check your blood sugar at home
- adjust what and when you eat, often with help from a dietitian
- stay gently active, for example with a walk after meals
- take medicine if diet and activity are not enough, as prescribed by your doctor
You may have extra scans to check your baby's growth, and your team will talk with you about the timing of birth. After birth, your blood sugar will usually be checked, and you may be offered a test in the months that follow, as gestational diabetes can raise the chance of type 2 diabetes later in life.
Call your midwife or diabetes team if
- you feel very thirsty, are passing a lot of urine, or feel unusually tired with a dry mouth
- your home readings are often outside the range your team gave you
- you feel shaky, sweaty or confused (and treat it as your team has advised)
- your baby's movements slow down or change
Pouring out your heart
A new diagnosis can make you feel that your body is letting you down. Bring those feelings honestly to God. The psalmist encourages us:
“Trust in him at all times; ye people, pour out your heart before him: God is a refuge for us. Selah.” (Psalm 62:8)
At all times includes the waiting room with the sickly-sweet drink and the evening you prick your finger and the number is higher than you hoped. You do not have to be cheerful before God. You can pour out the frustration, the fear and the hunger, and find Him a safe place.
A prayer for test day
Lord, I give You this test and whatever result it brings. Thank You for the people who are watching over my baby and me. If my body needs extra help, give me patience, wisdom and courage, and remind me that I am never a failure in Your eyes. Amen.
Frequently asked questions
When is the glucose test done in pregnancy?
Many clinics offer it between about 24 and 28 weeks, sometimes earlier if you have had gestational diabetes before.
Is gestational diabetes my fault?
No. It is mainly caused by pregnancy hormones affecting how your body uses insulin. With good care most women with gestational diabetes have healthy babies.
This article is for general information and encouragement, not medical advice. Please talk to your doctor or midwife about your own health and your baby's.
