Gestational diabetes is a type of diabetes that affects around 18% of pregnant women in the UK. 


What is gestational diabetes?

The levels of glucose your blood are controlled by the hormone insulin. Glucose is needed by the body to provide energy.

When you're pregnant, your body produces high levels of hormones to support the growth of your baby. Some of these hormones can stop insulin working as well as it normally does. Usually, the body responds by increasing the amount of insulin it produces. However, some women do not produce enough of this extra insulin, or the insulin produced is not used by the body (known as ‘insulin resistance’). This leads to high glucose levels in the blood and leads to gestational diabetes.

Gestational diabetes usually goes away after birth.

Careful management of the condition significantly reduces the risk of complications and most women will have a healthy pregnancy and a healthy baby.

What are the symptoms of gestational diabetes?

There are often no symptoms, although some women may develop symptoms if their glucose levels become too high. These include:

  • going to the toilet more than usual
  • feeling more tired than usual
  • being really thirsty
  • general itching or thrush
  • having a dry mouth

How is gestational diabetes diagnosed?

It's usually diagnosed by a blood test between 24-28 weeks. If you've had gestational diabetes in a previous pregnancy then you will normally be tested earlier on in your pregnancy.

Not all women are offered the test as standard. Your midwife will ask you about the risk factors associated with gestational diabetes and you'll be offered this test if needed.

Increased levels of glucose may be picked up when your urine is tested. Your midwife will check this during your antenatal appointments.

"I had no symptoms whatsoever, so it was a real surprise when it was diagnosed. I was offered a test due to a family history of diabetes and was so glad it was picked up early." - Rose

What causes gestational diabetes?

Doctors and researchers don't fully understand why some women develop the condition and others don't. However, they have identified areas of increased risk:

  • your body mass index is above 30
  • you've had gestational diabetes before
  • you have polycycstic ovary syndrome
  • you have had a large baby in a previous pregnancy (4.5kg/10lb or over)
  • have a family history of diabetes (parent, brother or sister)
  • you are of South Asian, Black or African Caribbean or Middle Eastern origin

Your midwife will arrange for you to have a blood test if any of these factors apply.

What does it mean for me, my baby and my pregnancy?

The more glucose there is in your blood, the more your baby will produce. This extra glucose may mean your baby grows larger and faster than usual and this can affect your birth options. Your baby's weight will be carefully monitored using ultrasound scans and you may be advised to have a planned Caesarean or an early induction if your baby is large.

Having gestational diabetes can also cause stillbirth, although the risk of this is low. If your condition is diagnosed and managed this risk reduces. It's incredibly important you attend your antenatal appointments and report any concerns about your baby's movements to your Maternity Unit.

However, gestational diabetes can be managed successfully and doesn’t have to take over your pregnancy, or affect the health of your baby.

It will probably mean a change to your expected pregnancy experience and there are likely to be changes to your birthing plan. There will be more trips to your healthcare team (look at this as a chance to check-in with your baby more, thanks to regular scans), testing of your blood glucose levels at home and a greater focus on your diet, which is also likely to see changes. These are all important, to ensure you and your baby are kept healthy throughout your pregnancy.

What treatment is available to me?

You'll have extra appointments with specialists after diagnosis - they'll be there to support you. The primary treatment for gestational diabetes is diet and exercise, as both have a direct impact on blood glucose levels. When diet and exercise aren’t enough to keep blood sugar levels within the normal range, you may need medication and/or insulin


Being diagnosed with gestational diabetes can be incredibly overwhelming. Try to remember that most women have healthy pregnancies and healthy babies. Don't be afraid to speak to your doctor or midwife about how you're feeling, they're there to care for you. 

If you want to speak to someone with similar experiences, Diabetes UK's Support Forum is an online community where you can share knowledge and experiences with other people with diabetes in pregnancy.