Gestational diabetes

Gestational diabetes is diabetes that develops during pregnancy. Having diabetes means that the body doesn’t deal with sugar (glucose) as it should, and this can mean there’s too much sugar in your blood and going to your baby

Most women diagnosed with gestational diabetes have otherwise normal pregnancies, with lifestyle changes or medication keeping their glucose under control. But because gestational diabetes is linked with problems such as pre-eclampsia and having a large baby and, in a small number of pregnancies, it can lead to the death of the baby before or during birth, it’s important that it's spotted

Some women are more likely to develop gestational diabetes than others, and your midwife will ask questions at your booking appointment to see if you fall into the ‘at risk’ group (see below). If you do, you’ll be tested for gestational diabetes at some time between 24 and 28 weeks. If you’ve had gestational diabetes in a previous pregnancy, you should be tested before 24 weeks, and the test should be repeated at 24—28 weeks if the first test was normal

You are more likely to get gestational diabetes if one or more of these apply

  • You have had gestational diabetes before
  • You have had a large baby before (4.5 kg/10 pounds or more)
  • You are very overweight (BMI above 30 kg/m2)
  • You have a parent, brother or sister with diabetes
  • Your ethnic background means you have a higher risk of developing diabetes (for example, having a South Asian, African-Caribbean or Middle Eastern background increases the likelihood)
  • You are over 40 years of age

If you have an increased risk of gestational diabetes

  • Talk to your midwife about it at booking
  • Check that you’re getting tested at the right time
  • Check when your test results will be available
  • Check your results have arrived and what they mean
  • Follow the advice of your midwife or doctor if you have a positive test


This short film about diabetes in pregnancy was produced for Our Chance, a campaign by the charities Sands and Best Beginnings to raise awareness of health issues in pregnancy
More information

The care you should receive from the NHS is described by the National Institute for Health and Clinical Excellence

The Royal College of Obstetricians and Gynaecologists have produced information on gestational diabetes

The charity Diabetes UK has a lot of information about gestational diabetes that covers symptoms and complications, testing and treatment and the care you should expect to get