Hyperglycaemia and pregnancy

Hyperglycaemia is caused by glucose levels rising too high, which can cause health problems. Taking care of yourself can help reduce the risk.

Hyperglycaemia is caused by glucose levels rising too high. If you have diabetes, you are also at risk of your glucose dropping too low (hypoglycaemia).

It's important to be able to recognise and treat hyperglycaemia. This is because it can lead to serious health problems if left untreated. But if you follow your treatment plan and monitor your glucose levels regularly, you can reduce the risk of hyperglycaemia. 

Your glucose level will go up and down during pregnancy, especially at the beginning of pregnancy. It’s important to be realistic, while doing your best to stay healthy. Talk to your healthcare team or look for peer support from other pregnant women in the same situation. You may need to make some changes to your diet, lifestyle and medication. 

Also, remember that you will have extra care throughout your pregnancy and you can contact your healthcare team at any time if you have any concerns.

Causes of hyperglycaemia 

Some things can trigger hyperglycaemia, including:

  • food, such as eating too many carbs, fast-acting carbs, snacking between meals
  • taking an insufficient dose of insulin before eating
  • not injecting your insulin early enough before eating (insulin needs to be injected on average 15 minutes before eating in the first trimester, increasing to 30-45 minutes before a meal as pregnancy progresses)
  • missing a dose of your diabetes medication or missing an insulin dose
  • overtreating an episode of hypoglycaemia
  • a change or reduction in exercise (find out more about diet and exercise with type 1 and 2 diabetes
  • taking certain medicines, such as steroids 
  • an illness, such as a cold 
  • stress (find out more about type 1 and 2 diabetes and your emotional health). 

Symptoms of hyperglycaemia

Symptoms of hyperglycaemia include:

  • increased thirst and a dry mouth
  • needing to pee frequently
  • tiredness
  • blurred vision
  • unintentional weight loss
  • recurrent infections, such as thrush, bladder infections (cystitis) and skin infections
  • feeling or being sick.  

How to prevent hyperglycaemia

There are ways to reduce the risk of hyperglycaemia.

  • Be careful with what you eat (eating sugary foods or fast-acting carbohydrates can affect your glucose level).
  • Stick to the treatment plan as agreed with your care team.
  • Be as active as possible (find out more about diet and exercise with type 1 and 2 diabetes).
  • Monitor your glucose level regularly. 

If you have hyperglycaemia or you are feeling unwell

If you have any form of diabetes, you should get urgent medical advice if you have hyperglycaemia that you cannot manage or you are feeling unwell (even if it’s just a cold).   

Diabetic ketoacidosis (DKA)

Diabetic ketoacidosis (DKA) is a serious problem that can happen in people with diabetes if their body starts to run out of insulin. This causes substances called ketones to build up in the body. This can be life-threatening if not spotted and treated quickly.

Symptoms usually develop over 24 hours but can come on faster.

In pregnancy, you are more likely to develop DKA if you:

  • have an infection, such as the flu or a urinary tract infection
  • are not following your treatment plan, such as missing does of insulin
  • have an injury or had surgery
  • are taking certain medicines such as steroid medication
  • have been binge drinking 
  • have been using recreational drugs. 

Taking recreational drugs or drinking alcohol isn’t safe during pregnancy. If you find it hard to avoid alcohol, talk to a midwife, doctor or pharmacist. They will not judge you and will understand that you are trying to do your best to keep your baby safe. They will be able to get you any extra support you need.

Preventing diabetic ketoacidosis

Checking your glucose regularly will give you the chance to treat any increase quickly and reduce your chances of getting DKA. 

People with type 1 diabetes are at higher risk of DKA, although anyone with diabetes can get it. If you have type 1 diabetes, you should be given ketone testing strips and a monitor at the beginning of your pregnancy. You should check the ketone levels in your blood if your glucose is too high or if you are unwell. 

If you have type 2 diabetes

If you have type 2 diabetes, you won’t usually be given a ketone testing kits when pregnant because DKA is not common in type 2 diabetes. However, pregnancy increases the risk of DKA. So contact your healthcare team immediately if you are unwell at any time during your pregnancy or if you have hyperglycaemia.

Symptoms of diabetic ketoacidosis

Signs of DKA include:

  • needing to wee more than usual
  • feeling very thirsty
  • being sick
  • stomach pain
  • breath that smells fruity (like pear drop sweets or nail varnish)
  • deep or fast breathing
  • feeling very tired or sleepy
  • confusion
  • passing out. 

Because you may get confused or pass out, it’s important that the people around you understand these symptoms and what to do if you need help.

Symptoms usually develop over 24 hours, but can come on faster.

When to get medical help

Go to your nearest hospital straight away if you think you have DKA, especially if you have a high level of ketones in your blood (above 1.5mmol/l or more).

DKA is an emergency and needs to be treated in hospital.

NHS. Hyperglycaemia (high blood sugar level) https://www.nhs.uk/conditions/high-blood-sugar-hyperglycaemia/ (Page last reviewed: 8 August 2018 Next review due: 8 August 2021)

NICE (2015). Diabetes in pregnancy: management from preconception to the postnatal period. National Institute for health and care excellence https://www.nice.org.uk/guidance/ng3
NHS. Diabetic ketoacidosis https://www.nhs.uk/conditions/diabetic-ketoacidosis/ (Page last reviewed: 1 May 2020 Next review due: 1 May 2023)

Review dates
Reviewed: 20 July 2020
Next review: 20 July 2023

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