Gestational diabetes is a type of diabetes that occurs during pregnancy – in most cases it disappears after the baby is born.
You are normally screened for gestational diabetes between weeks 25 and 28 of your pregnancy, and if you are diagnosed with it, don’t be alarmed as there are ways it can be effectively managed.
Women who have previously been diagnosed with gestational diabetes, or who may be at high perceived risk, should be tested when pregnancy is confirmed and then again at 24 weeks if GD was not diagnosed earlier.
Diagnosing gestational diabetes
Who is at risk of gestational diabetes
Gestational diabetes occurs in roughly 5 to 10 per cent of pregnancies and there is no single known reason why.
Women at greater risk of developing gestational diabetes are:
- Women over 25 years of age
- Women with a family history of Type 2 diabetes
- Women who are overweight
- Women who have previously had gestational diabetes during pregnancy
- Women who have previously delivered a large baby (greater than 4kg)
- Women who have have Polycystic Ovary Syndrome (PCOS)
- Women from certain ethnic groups including: Indigenous Australians; Torres Strait Islanders; Middle Eastern; East Asian (Chinese, Vietnamese); Pacific Island (Polynesian/Melanesian).
How is gestational diabetes diagnosed
Gestational Diabetes is diagnosed using specific blood tests – your health care provider will offer a gestational diabetes screening test as a part of routine antenatal testing.
They will suggest one of the following screening tests:
- The Glucose Challenge Test (GCT) is a 1-hour, non-fasting screening test. You’ll be given a glucose drink and blood will be taken an hour afterwards to test glucose levels.
- The Oral Glucose Tolerance Test (OGTT). This is a more thorough, 2-hour, fasting screening test. Blood is taken before drinking the glucose drink and two hours afterwards.
These tests are important as gestational diabetes can be treated and managed once detected.
The risks of unmanaged gestational diabetes include:
- Significantly increased risk of stillbirth or miscarriage
- Excessive fetal growth (creating babies in excess of 4kg weight)
- Complications and higher risk of injury during birth
- Low blood glucose levels for baby immediately following birth
Managing Gestational Diabetes
It can come as quite a shock to find out that you have gestational diabetes – but the good news is that it can be effectively managed and treated.
There are three main things aspects of effective management of gestational diabetes:
Monitoring blood glucose levels
When you’re diagnosed with gestational diabetes your doctor or diabetes educator will show you how to monitor your own blood glucose levels at home using a simple blood glucose meter. They will advise on what your target levels should be and when you should test.
It is important to monitor your levels to make sure that your healthy eating and exercise is keeping your blood sugar levels within the desired range. It helps you to learn more about the link between your food, exercise and blood glucose levels so you can better manage it.
If you find that you’re still often outside the desired range and your blood glucose levels can not be managed by diet and exercise alone, your health care provider will suggest medication.
It is highly recommended that you consult a dietitian for advice on healthy eating patterns, diet, and proper nutrition for both yourself and your baby.
Here are some tips to make healthy food choices for gestational diabetes:
- Eat small amounts of nutritious foods often
- Choose a variety of healthy, nutritious foods.
- Include foods which are sources of calcium, iron, folate and other critical nutrients.
- Limit fat intake – especially saturated fats. Choose monounsaturated fats (olive or canola oils).
- Limit ‘energy-dense’ junk foods high in saturated fat, sugar, and salt.
- Include moderate quantity of preferably low-GI carbohydrates with every meal (wholegrains, cereals, fruit, vegetables, pasta, rice).
- Avoid all sugary cordials and soft drinks.
Participation in moderate physical activity can be very important in helping to maintain blood glucose levels as close to normal as possible. Even a brisk, 45-minute walk four times per week, or similar equivalent level of exercise and physical exertion, can have beneficial effects in improving insulin sensitivity to lower your blood glucose levels.
Insulin sensitivity is the ability of your body to use available insulin. The benefit of physical activity in increasing the metabolic rate can last for up to 24-36 hours and it can also improve fitness and help prepare the mother for the birth of the baby.
Gestational diabetes after delivery
Blood glucose levels usually return to normal immediately after birth. It is common to monitor the mother’s blood glucose levels for up to two days after delivery, and no monitoring after that if everything appears normal.
An oral glucose tolerance test (OGTT) is recommended six weeks after the birth and will usually be normal. It is important for your long-term health that you follow-through to make sure that this test is performed in the hectic weeks following pregnancy.
Your baby might have hypoglycaemia or low blood glucose when born so their blood glucose levels will usually be monitored. In some cases, supplementary glucose might be recommended for the baby.
Mothers who develop gestational diabetes are at increased risk of developing Type 2 diabetes later in life. Your baby might also be more likely to develop Type 2 diabetes later in life. There are plenty of ways to reduce your risk of developing Type 2 diabetes including, maintaining a healthy weight, eating a nutritious balanced diet and staying active. It is also recommended that you chat to your health care provider about having your blood glucose levels tested every couple of years.
– compiled using information from Diabetes Australia