Monitoring your own glucose levels

If you have gestational diabetes, measuring your own blood sugar levels will be something you do regularly.

If you have gestational diabetes, you can reduce the risk of problems in your pregnancy by controlling your blood sugar levels. To do this, you will need to check your blood sugar levels a few times a day for the rest of your pregnancy.

You’ll be given a testing kit so you can do this yourself. It involves using a device that pricks your finger, so you can put a drop of your blood on a testing strip. Your healthcare team will explain:

  • what levels to aim for
  • how to test your blood sugar level
  • when and how often to check (usually before breakfast and also 1 hour after each meal).

Your target blood sugar levels

Your healthcare team will talk to you about what blood sugar levels to aim for. This will vary at different times of the day – for example, it will be higher after meals than first thing in the morning.

Blood sugar is measured in mmol/l. This stands for millimoles of sugar per litre of blood.

The ideal blood sugar levels will vary from person to person. But for most pregnant people with gestational diabetes, the ideal target blood sugar levels are as follows.

Gestational diabetes glucose levels

  • when you wake up, before any food or drink (known as ‘fasting’): Less than 5.3 mmol/litre
  • 1 hour after meals: Less than 7.8 mmol/litre
  • 2 hours after meals: Less than 6.4 mmol/litre

These numbers are for general guidance. Follow the advice of your healthcare team if they give you different levels to aim for. 
They will also explain what levels are too high, or too low (known as hypoglycaemia).

How do I monitor my blood sugar levels?

To test your blood sugar levels, you’ll need:

  • a blood testing meter
  • a finger prick device
  • some test strips 
  • a lancet (a very short, thin needle)
  • a sharps bin, so you can throw the used needles away safely

Watch this film from Diabetes UK or read the steps below. Your healthcare team should show you how to do it the first time.


Try to prick the side of your finger, near the tip. You won’t feel it as much.

  1. Wash your hands with soap and warm water. Don’t use wet wipes as the glycerine in them can affect the test result. 
  2. Make sure your hands are warm. This makes it easier to get blood and it won’t hurt as much.
  3. Put a test strip into the meter to turn it on. Some meters have test strips built in. 
  4. Remove the cap from your finger prick device and put in a new lancet. Then, put the cap back on and pull or click the plunger to set the device.
  5. Choose which finger to prick. Avoid your thumb and index finger (finger next to your thumb). And don’t prick the middle of a finger, or too close to a nail. 
  6. Place the device against the side of your finger and press the plunger. Use a different finger each time and a fresh spot.
  7. Take your meter with the test strip and hold it against the drop of blood. It’ll tell you if the test strip is filled, usually by beeping.
  8. Before you look at your reading, check your finger. Use a tissue to stop bleeding, then use the same tissue to take out the lancet and throw it away in your sharps bin.
  9. By this time, your meter will show the result. Write it down.

You can use the same tissue to take out the test strip and throw that away too. Taking out the strip will likely turn the meter off.

"The first week when I was recording my blood sugars, the dietitian said, ‘Once we’ve seen your results, we can go through what you’re doing right and wrong’. It turned out I was eating too much fruit and yoghurt with my lunch." 


When should I measure my blood sugar?

You will need to measure your blood sugar levels throughout the day. Your diabetes team will explain when to test, as it can vary from person to person.

When you wake up  

You need to measure your blood sugar level each morning when you get up, before you have any food or drink. This is called your ‘fasting blood sugar level’, because you will have an empty stomach. You must not have eaten or drunk anything, apart from water, for at least eight hours.

Before or after every meal  

You will be asked to test your blood sugar level around the time of a meal. Some services test before eating (‘pre-prandial monitoring’) while others test one or two hours after a meal (‘post-prandial monitoring’). 

Testing a few minutes late will not affect your reading too much. But try to test as close to the required time as you can. It may help to set a timer after your meal.

At night

If you are taking insulin, you may also need to test your blood sugar level before you go to bed (or even during the night, although this is unusual).

"When we did go out for a special meal or two, and I'd have a little bit of cheesecake or something, it really affected my sugar levels." 


How do I read the results?

Your blood sugar levels tell you if your gestational diabetes is under control. When you use a finger prick test, it should show your blood sugar levels in mmol/l (millimoles per litre).

Your healthcare team will explain how to read the results. They will ask you to write them all down, so they can see them at your check-ups.

What do I do if my blood sugar is too high or low?

Your blood sugar levels should be within the ideal levels that you agree with your healthcare team. If they are not, follow the advice given by your healthcare team, or contact them if you’re not sure.

If your blood sugar levels are outside the ideal range, you may need treatment, such as metformin tablets or insulin injections to keep your blood sugar under control. Learn more about treatments for gestational diabetes.

You will have contact with your diabetes team every 1 to 2 weeks during your pregnancy, by phone, email, or in person. You should be given a direct number to call if you have questions in between your appointments. 

They are there to give you advice and support, including monitoring your blood sugar levels, explaining ways to keep your blood sugar under control, and letting you know if your treatment needs to change.

Read more about the people in your healthcare team and the care you should expect.

Continuous glucose monitors

A small number of pregnant people are offered a continuous glucose monitor (CGM). This lets you check your blood sugar levels without having to prick your fingers as often.

It might be an option if you are taking insulin and have problems with very low or unstable blood sugar.

You can find out more about CGMs on the Diabetes UK website.

More support and information

Contact the Diabetes UK Helpline:

In England, Wales or Northern Ireland, call 0345 123 2399 (Monday to Friday, 9am to 6pm) or email [email protected]

In Scotland, call 0141 212 8710 (Monday to Friday, 9am to 6pm) or email [email protected]

You can also speak to the Tommy's Midwives Helpline on 0800 014 7800 (Monday to Friday, 9am to 5pm) or email us at [email protected]

National Institute for Health and Care Excellence (2020). Diabetes in pregnancy: management from preconception to the postnatal period. NICE guideline 3. Available at: (Accessed January 2024) (Page last reviewed 16/12/2020)

Royal College of Obstetricians & Gynaecologists, Diabetes UK (2021). Gestational diabetes - Information for you. Available at: (Accessed January 2024) (Page last reviewed 09/2021)

Diabetes UK (nd). Checking your blood sugar levels. Available at: (Accessed January 2024)


Review dates
Reviewed: 15 February 2024
Next review: 15 February 2027