Tommy's PregnancyHub

What are the risks of gestational diabetes?

Gestational diabetes can cause problems in pregnancy, but these risks can be reduced with careful management.

There are some risks associated with having gestational diabetes. But a risk only means there is a chance that something might happen, not that it definitely will. Most women with gestational diabetes have healthy pregnancies and healthy babies, especially if their condition is diagnosed and managed well during pregnancy. Try to remember that your healthcare team will support you through your pregnancy.

"I suppose everybody who is pregnant has something – there’s always something that doesn’t go right – but I was really worried. You just want it to be perfect, don’t you?"


Some babies develop low blood sugar or yellowing of the skin and eyes (jaundice) after they are born. This can usually be monitored at home with the support of your midwife or health visitor, but some babies will need hospital treatment.

Having a large baby

If your glucose level is high, your body will produce more insulin. The same will happen to your baby, which can make them grow larger than usual. Large birthweight is called macrosomia. Babies weighing more than 4kg (8lb 8oz) at birth are considered macrosomic.

Large birthweight increases the risk of birth trauma, including bone fractures, breathing difficulties or nerve damage for baby. It can also cause shoulder dystocia. This is when the baby’s shoulder gets stuck in your pelvis once the head has been born.

Your baby's weight will be monitored carefully in pregnancy using ultrasound scans. If your baby is large, you may be advised to have an early induction (starting labour artificially) or planned caesarean section.

Read more about giving birth with gestational diabetes.


Polyhydramnios is when there is too much amniotic fluid (the fluid that surrounds the baby) in the womb. This can cause premature labour, problems with the baby’s position or problems with position of the umbilical cord at birth.

“I was diagnosed after polyhyrdramnios was picked up at a scan at 28 weeks. I had no risk factors, and I was absolutely gutted. I have a history of eating disorders so I was scared that following a strict diet would trigger unhelpful behaviours. Luckily, I was able to control things with diet and exercise. My little boy (my second child) was born after an induction (unrelated to my gestational diabetes) at 38 weeks, happy and healthy.”



Having gestational diabetes can cause stillbirth, but the risk is low. Remember that getting a diagnosis and careful management of gestational diabetes reduces this risk.


This is a condition that causes high blood pressure during pregnancy. It can lead to pregnancy complications if it is not treated.

Early signs of pre-eclampsia include having high blood pressure and protein in your urine. It's unlikely that you'll notice these signs, but they should be picked up during your routine antenatal appointments. Find out more about pre-eclampsia.

Premature birth

Your baby may be born early because your healthcare team believe that it’s better for you to have an induction or caesarean section rather than carrying on with the pregnancy. Some studies have also shown that some women with gestational diabetes go into premature labour naturally.

Read more about premature birth.

'You find all these things out, and they are all incredibly rare, but I did really worry. That’s why I was so motivated to manage my glucose levels.' 


After your baby is born

Gestational diabetes can cause problems for you and your baby after labour and in the long term. If you’ve had gestational diabetes, you are also at higher risk of developing type 2 diabetes during your life. Babies of mothers with gestational diabetes may also be at greater risk of developing obesity or diabetes in later life.

You can reduce your risk of health issues in the future by maintaining a healthy weight, eating a balanced diet and taking regular exercise.

Find out more about the long-term implications of gestational diabetes.

Keeping the risks in perspective

It is natural to find these possibilities worrying but try to keep things in perspective. Firstly, every pregnancy carries some risks. Secondly, although you can’t remove these risks altogether, there are ways that you can reduce them.

Talk to your midwife if you have any of the risk factors for gestational diabetes but you have not been tested. If you are diagnosed, the best thing you can do is follow your healthcare professional’s advice on how to manage your condition and go to all your extra antenatal care appointments.

Remember, most women who develop diabetes in pregnancy have healthy pregnancies and healthy babies, especially if their condition is diagnosed and properly managed.

Your mental health

Some women take a gestational diabetes diagnosis in their stride, while others may find it stressful. Talk to your midwife if you are feeling very worried or anxious about it. They will be able to reassure you, or signpost you to more help and support, if you need it.

You can also call speak to our midwives on our pregnancy line on 0800 014 7800 (Monday to Friday, 9am to 5pm), or email us at [email protected].

Find out more about your mental health before, during and after pregnancy.

Royal College of Obstetricians and Gynaecologists (2013) Gestational Diabetes.

NHS Choices. Gestational Diabetes (Page last reviewed: 06/08/2019. Next review due: 06/08/2022)

Mitanchez, D et al (2015) What neonatal complications should the paediatrician be aware of in case of maternal gestational diabetes? World Journal of Diabetes. 2015 Jun 10; 6(5): 734–743. doi: 10.4239/wjd.v6.i5.734

NICE (2015). Diabetes in pregnancy: management from preconception to the postnatal period. National Institute for health and care excellence

Review dates
Reviewed: 23 July 2020
Next review: 23 July 2023

This content is currently being reviewed by our team. Updated information will be coming soon.