Gestational diabetes is a specific type of diabetes that occurs in pregnancy.
The good news is taking steps such as adopting a healthier diet and being more active will lower those risks, while improving health and well-being for you and your family.
What is gestational diabetes?
Gestational diabetes affects about one in seven to eight pregnant women in Australia. Women are screened for gestational diabetes at around 24 to 28 weeks gestation using a glucose tolerance test. Gestational diabetes is diagnosed when blood glucose levels, also called blood sugar levels, are higher than the normal range.
Screening is designed to ensure women with gestational diabetes receive treatment as early as possible to minimise health risks for both the mother and the baby. Risks include having a baby born weighing more than four kilograms, and the need to have a caesarean section. Management of gestational diabetes includes close monitoring of blood glucose levels, a healthy diet, and being physically active.
The risk of developing type 2 diabetes increases markedly in the first five years following gestational diabetes, with risk plateauing after ten years. Women who have had gestational diabetes have more than seven times the risk of developing type 2 diabetes in the future than women who haven’t had the condition.
Type 2 diabetes
If type 2 diabetes goes undiagnosed, the impact on your health can be high – especially if it’s not detected until complications arise.
Early signs and symptoms of type 2 diabetes include extreme thirst, frequent urination, blurred vision, frequent infections and feeling tired and lethargic.
Long-term complications include an increased risk of heart disease and stroke, damage to nerves (especially those in the fingers and toes), damage to the small blood vessels in the kidneys, leading to kidney disease, and damage to blood vessels in the eyes, leading to diabetes-related eye disease (called diabetic retinopathy).
If you’ve ever been diagnosed with gestational diabetes, here are five things you can do to lower your risk of developing type 2 diabetes.
1. Monitor your diabetes risk
Although gestational diabetes is a well-known risk factor for type 2 diabetes, some women have not been informed of the increased risk. This means they may not be aware of the recommendations to help prevent type 2 diabetes.
All women diagnosed with gestational diabetes should have a 75g oral glucose tolerance test at 6–12 weeks after giving birth. This is to check how their body responds to a spike in blood sugar after they’ve had the baby, and to develop a better picture of their likelihood of developing type 2 diabetes.
From that point, women who have had gestational diabetes should continue to have regular testing to see whether type 2 diabetes has developed.
Talk to your GP about how to best monitor diabetes risk factors. Diabetes Australia recommends a blood glucose test every one to three years.
2. Aim to eat healthily
Dietary patterns that include vegetables and fruit, whole grains, fish and foods rich in fibre and monounsaturated fats are associated with a lower risk of developing type 2 diabetes.
In more than 4,400 women with prior gestational diabetes, those who had healthier eating patterns, assessed using diet quality scoring tools, had a 40-57 per cent lower risk of developing type 2 diabetes compared with women with the lowest diet quality scores.
Glycaemic index (GI) ranks carbohydrate-containing foods according to their effect on blood glucose levels. The lower the GI, the slower the rise in blood sugar levels after eating. Research suggests that a higher GI diet, and consuming lots of high GI foods (glycaemic load), is associated with a higher risk of developing type 2 diabetes, while a lower GI diet may lower the risk of type 2 diabetes.
3. Be as active as possible
Increasing your physical activity level can help lower your risk of developing type 2 diabetes.
Engaging in 150 minutes of moderate-intensity exercise per week, such as walking for 30 minutes on five days a week; or accumulating 75 minutes of vigorous-intensity physical activity a week by swimming, running, tennis, cycling, or aerobics, is associated with a 45 per cent lower risk of developing type 2 diabetes after having had gestational diabetes. Importantly, both walking and jogging produced a similar lower risk of type 2 diabetes.
In contrast, prolonged time spent watching TV was associated with a higher risk of type 2 diabetes in women with a history of gestational diabetes.
Strength training is also important. A large study of 35,754 healthy women found those who engaged in any type strength training, such as pilates, resistance exercise or weights, had a 30 per cent lower rate of developing type 2 diabetes compared to women who did not do any type of strength training.
Women who did both strength training and aerobic activity had an even lower risk of developing either type 2 diabetes or heart disease.
4. Breastfeed for as long as you can
Research shows breastfeeding for longer than three months reduces the risk of developing type 2 diabetes by about 46 per cent in women who have had gestational diabetes. It is thought that breastfeeding leads to improved glucose and fat metabolism.
The Nurses Health Study followed more than 150,000 women over 16 years. It found that for every additional year of breastfeeding, the risk of developing type 2 diabetes was reduced by 14-15 per cent – even in mothers who had not been diagnosed with gestational diabetes.
Organisations such as the Australian Breastfeeding Association and lactation consultants offer support to help all women, including those who have had gestational diabetes, to breastfeed their infants for as long as they choose.
5. Keep an eye on your weight
Weight gain is a known risk factor for developing type 2 diabetes. In a study of 666 Hispanic women with previous gestational diabetes, a weight gain of 4.5kg during 2.2 years follow-up increased their risk of developing type 2 diabetes by 1.54 times.
Another study saw 1,695 women with previous gestational diabetes followed up between eight to 18 years after their diagnosis. This research found that for each 5kg of weight gained, the risk of developing type 2 diabetes increased by 27 per cent.
Aiming to modify your eating habits and being as active as you can will help with weight management and lower the risk of developing type 2 diabetes. Within interventions that support people to adopt a healthy lifestyle, one review found every extra kilogram lost by participants was associated with 43 per cent lower odds of developing type 2 diabetes.
Clare Collins, Professor in Nutrition and Dietetics, University of Newcastle; Hannah Brown, PhD Candidate Nutrition and Dietetics, University of Newcastle, and Megan Rollo, Postdoctoral Research Fellow, Nutrition & Dietetics, University of Newcastle