Tommy's PregnancyHub

Testing your glucose levels with type 1/2 diabetes

If you have type 1 or 2 diabetes, managing your blood glucose levels can now be much harder in pregnancy. Testing is an important part of self-care.

If you had type 1 or 2 diabetes before you became pregnant, managing your blood glucose levels can now be much harder. As your body changes, so do your blood glucose levels.

If you have type 1 diabetes, and those with type 2 and are having two or more insulin injections a day, then you should test:

  • when you wake up (before breakfast)
  • before other meals
  • one hour after each meal
  • at bedtime.

If you have type 2 and are managing your diabetes with diet and exercise alone, taking tablets, or taking one insulin injection a day, then you should test:

  • when you wake up (before breakfast)
  • one hour after each meal.

You may also be advised to test your blood glucose levels two hours after meals.

The levels of certain hormones tend to be higher in the morning, which means that you are more insulin resistant around breakfast time. This rise in blood glucose levels, sometimes called the ‘dawn phenomenon’, does not only happen during pregnancy.

If you notice that your fasting blood glucose levels are consistently high, talk to your healthcare team who can help you.

'The more often you test, the better your control is. There aren’t many pregnant diabetics who aren’t testing all the time. And when you’re pregnant, you have to test after your meals, as well as before.' Sara, mum of two


It is also more likely that you may have reduced awareness of the warning signals of hypoglycaemia when you are pregnant. This is called hypoglycaemia unawareness. If you are aiming for much tighter control, you will be paying much more attention to your levels, so you are likely to now notice changes that you might not have noticed before. Many women feel that they are doing everything they can and that their levels feel very out of control.

Your insulin needs will continue to rise

During pregnancy your insulin need will continue to rise until around 35 or 36 weeks, at which point it should stabilise. If you are having frequent hypoglycaemic episodes by the third trimester, contact your healthcare team to check that everything is OK. 

Read more about the third trimester with type 1/2 diabetes

'Because I had to get my control very fine, it was almost like learning to be a diabetic all over again. I had to change quite a lot from when I was first diagnosed. It was pretty rubbish in a way.' Hazel, mum of one

You will occasionally have high levels

Try not to worry too much about the occasional high reading. As long as your blood sugar levels are not regularly high, one or two readings that are out of the recommended range will not be a problem.

  1. NICE (2015) Diabetes in pregnancy: management of diabetes and its complications from preconception to the postnatal period, NICE guideline, National Institute for Health and Care Excellence
  2. Mayo Clinic. Diabetes, Reviewed Oct 23, 2014.
  3. Vambergue A, Fajardy I (2011) Consequences of gestational and pregestational diabetes on placental function and birth weight, World J Diabetes. 2011 Nov 15; 2(11): 196–203. Published online 2011 Nov 15. doi:  10.4239/wjd.v2.i11.196
  4. Diabetes in pregnancy, Information for the public, National Institute of Health and Care Excellence
Review dates

Last reviewed: 1 September, 2015
Next review: 1 September, 2018