Between three and 20 per cent of pregnant women develop gestational diabetes, depending on their risk factors.

All pregnant women should be screened for gestational diabetes within 28 weeks of pregnancy.

What is Gestational Diabetes Mellitus?

Gestational diabetes mellitus is a type of diabetes that occurs during pregnancy. Your body cannot produce enough insulin to handle the effects of a growing baby and changing hormone levels. Insulin helps your body to control the level of glucose (sugar) in your blood. If your body cannot produce enough insulin, your blood glucose (sugar) levels will rise.

The good news

  • Your baby will not be born with diabetes.
  • Gestational diabetes can be managed and you can expect to have a happy, healthy baby.

What does gestational diabetes mean for my baby?

If left undiagnosed or untreated, gestational diabetes can lead to high blood glucose (sugar) levels. This increases the risk that your baby will weigh more than 4 kg (9lbs) and will have a difficult delivery. Gestational diabetes can also increase the risk of your baby becoming overweight and developing type 2 diabetes in the future.

What does gestational diabetes mean for me?

A diagnosis of gestational diabetes means you will be working closely with your health-care team to manage your blood glucose (sugar) levels and keep them in the target range. This will help you avoid complications in labour and delivery. After your baby is born, blood glucose (sugar) levels will usually return to normal. However, you are at greater risk for gestational diabetes in your next pregnancy and of developing type 2 diabetes in the future.

Risk factors for gestational diabetes


  • 35 years of age or older
  • From a high-risk group (Aboriginal, Hispanic, South Asian, Asian and African)
  • Obese (BMI of 30kg/m2 or higher)
  • Giving birth to a baby that weighed more than four kilograms (nine pounds)


  • Corticosteroid medication


  • Prediabetes
  • Gestational diabetes in a previous pregnancy
  • A parent, brother or sister with type 2 diabetes
  • Polycystic ovary syndrome (PCOS) or acanthosis nigricans (darkened patches of skin)

How is gestational diabetes managed?

Choose a healthy diet

Enjoy foods from all four of the food groups and spread out your foods by eating smaller meals and snacks. This will help you manage your blood glucose (sugar) levels and provide the best nutrition for you and your growing baby.

Achieve a normal pregnancy weight gain

The amount of weight you gain will vary depending on your weight before your pregnancy. Weight loss is not recommended. Talk to your health-care provider about appropriate weight gain for you.

Be physically active

Regular physical activity can help control your blood glucose (sugar) levels. It can also help you:

  1. Boost your energy
  2. Sleep better
  3. Reduce stress
  4. Reduce pregnancy discomfort
  5. Prepare for childbirth
  6. Get your body back faster after childbirth

Talk to your health-care provider about the right type and amount of activity for you.

Check your blood glucose at home

Checking your blood glucose (sugar) with a blood glucose (sugar) meter will help you and your health-care team manage your gestational diabetes.

Take insulin, if needed

Sometimes healthy eating and physical activity are not enough to manage blood glucose (sugar) levels and your health-care provider may recommend insulin injections for the duration of your pregnancy. Insulin will help keep your blood glucose (sugar) level within your target range. This will help to keep you and your baby in good health.

Your health-care team can answer your questions and support you through this important time in your life. Your team may include your doctor, nurse and dietitian, but remember: the most important member of your health-care team is you!