Myth-busting insulin for gestational diabetes

Myth-busting insulin for gestational diabetes

Gestational diabetes is a roller coaster ride from start to finish. There is a lot of information to navigate and often at a session with your diabetes educator you don’t know what questions to ask. So we pulled together an extensive list of questions about insulin for gestational diabetes. We wanted to highlight the positives and to bust the myths. We hope that after reading this you’ll feel more informed and less anxious about insulin treatment.

Written by Natasha Leader, Accredited Practising Dietitian & Credentialled Diabetes Educator

Do many women with GDM have to take insulin?

It tends to depend on your treatment centre and which timing and targets your health practitioners are using. For example you may be advised to check your blood glucose level at 1 hour or 2 hours after the meal. There may also be some variation in the target level of glucose that your doctor/diabetes educator uses i.e may be < 7.4 or 8.0 1hr or <6.7 or 7.0 for 2hr time point. The percentage of women who need insulin is usually between 20 and 60%.

Have I failed if I end up having to take insulin?

Absolutely not. The need for insulin is related to how much insulin your body is able to make and whether this is enough to process the amount of carbohydrate food you and baby need to stay well. In most cases it is not a reflection of the effort you are making with your diet.

Is the insulin going to harm my baby in any way?

Insulin will not harm your baby but high glucose levels may. Insulin is used because it only crosses the placenta in very small amounts (compared with oral agents) and therefore is considered the safest way to control your blood glucose levels if diet and exercise alone are not enough.

Are there any long-term effects from taking insulin?

No. Taking injected insulin is just increasing the total available amount of insulin (adds to what you are already secreting) in order to better process the carbohydrates you are eating.

Will my body get used to taking it and will I have to keep taking it after my baby is born?

No. Your body doesn’t get used to the insulin and it doesn’t affect the amount of insulin your body is still making. The majority of women who need insulin to manage their gestational diabetes will stop it at delivery or even perhaps a little before this. The need for insulin is related to the effect of the placental hormones, so once the placenta is delivered blood glucose control rapidly returns to normal for most women.

Do the needles hurt?

Insulin is injected with an extremely fine and short needle into fat tissue just under the skin. Compared to checking your blood glucose levels with fingerprick device (which is not pleasant) most women can’t believe once they try insulin that they can’t feel it as much as they anticipated. It is normal to be scared about ‘injections’ as most injections are felt – but remember those injections are needles going (deeper) into veins or muscle tissue. With insulin, you should use a new needle each time to ensure it remains super sharp. 4mm needles are the standard used these days. You will be shown how to use insulin and should have a practice go while you are with your healthcare professional.

Where do I inject the insulin?

Insulin is injected into your belly region. This is the preferred area as there is good fat coverage (even if you are slim) and it is not an area subject to variation in blood flow. If you were to inject into your leg then get up and walk around it may affect the action of the insulin, making it more unpredictable. Many women worry about the needle hurting the baby. The needle is not going to go near your baby- even towards the end of a pregnancy when you can feel a foot or elbow, the needle is going just below the skin. You have fat, then layers of muscle, then the uterine wall and amniotic fluid still below which keeps the baby quite some distance from the needle.

Isn’t there a non-injectable alternative to insulin?

No, not as yet. There is ongoing research into the possibility of inhaled insulin however there is considerable way to go with this before it might be a useful option.

Why can’t I take an oral medication instead of injecting insulin?

There are a couple of oral medications that are used by some doctors to manage glucose levels in pregnancy. These are Metformin and in the US Glibenclamide and Glyburide. Many doctors don’t feel comfortable using these as treatment options due to the potential risks to mother and/or baby for example hypoglycaemia in the baby or simply not knowing enough about the long term impact on the child (as these drugs cross the placenta in greater quantity). It is important to discuss use of any medication with your doctor.

What is insulin made from? Is it synthetic drug?

These days insulin is made synthetically from DNA material in the laboratory. It is very close in structure to human insulin and less likely to cause problems with allergy compared with when insulin was derived from animal sources.

How do I know if I’m taking the right amount? Can I overdose on insulin?

Your insulin doses are determined by reviewing your blood glucose levels. We base your insulin dose/s on the overall pattern of your results. Your results should be reviewed regularly and doses adjusted as needed. There is no ‘right amount’ in the sense that you should not worry if you are taking 30 units when your friend may only need 4 units. The right amount is the amount to keep your blood glucose level to target. Everyone’s body is different.

It is possible to take too much insulin and it is important that if you are using insulin that you keep your carbohydrate intake consistent. The difference between the injected insulin and your own is that the injected insulin can’t tell what you are eating or doing so if you eat less than usual but take your usual insulin dose, your blood glucose level may drop too low.

Likewise if you don’t usually do much activity after your meal but one day spend hours walking around the shops, you also may find you end up with a low blood glucose level. Low blood glucose levels are avoidable in most circumstances but I it is important you are taught about the causes and management for them should they occur.

If I’m taking insulin, does that mean I can go back to eating what I want, when I want? Won’t the insulin take care of my blood glucose levels for me?

If only! Insulin is an additional therapy on top of your diet and exercise. Unfortunately the placental hormones make it difficult to eat freely and merely ‘match’ your insulin dose to your carbohydrate intake. Keeping a consistent carbohydrate intake and activity level will make your diabetes much easier to manage.

Is it dangerous to exercise if I’m taking insulin? Can it bring on a hypo?

It isn’t dangerous to exercise but as exercise can reduce your blood glucose level it is important to be aware of the potential for a low blood glucose level (a hypo). It is useful to try and keep your activity regular or otherwise take any extra activity into account and perhaps discuss a lower insulin dose for those occasions. Eating a little extra carbohydrate to cover activity is also something you could discuss with your health care provider.

Do I have to wake up in the night to re-inject insulin?

No. Insulin is usually given at mealtimes (before you eat) or in the evening (ideally 930-10pm). You shouldn’t need to alter your routine in order to manage insulin. If you have a much earlier bedtime than 10pm then your doctor may prescribe a different form of insulin to ensure it is still working at the right time overnight to control your fasting glucose level.

What happens during labour if I’m on insulin?

For most women insulin is stopped for labour though it depends on the amounts and types being used. It is recommended that your treating doctor/educator discuss management for induction/caesarean section/ labour as doses may be continued or altered depending on current blood glucose level results.

Does taking insulin increase the chance of my baby being diabetic?

Taking insulin is not related to your baby’s risk of developing diabetes. In fact having GDM doesn’t mean your baby will get diabetes. However the fact that you’ve developed GDM means you are high risk of developing diabetes in the future and studies do show that if you need insulin while pregnant you are more likely to develop impaired glucose tolerance. This is not due to using insulin but rather the other way around i.e. there is more disturbance to your glucose levels hence you need insulin in the first place.

If I’m taking insulin this pregnancy, will I automatically have to take it if I get GDM again?

Every pregnancy is different and if there are modifiable risk factors for why you developed GDM that you address (such as losing excess weight) then you may even avoid developing GDM at all. However, if you do get GDM again it is not automatic that you will again need insulin just because you did the last time.

Have I damaged my pancreas and my body’s ability to naturally process the glucose in my blood? Will my body be able to function normally again even after the GDM has gone away?

No you definitely haven’t irreparably damaged your body. For most women gestational diabetes is a temporary form of diabetes and therefore the pancreas is not permanently damaged. In fact the pancreas is not damaged at all – it is the effect of the placental hormones on your muscle and liver cells causing insulin resistance that is the main problem in gestational diabetes. Around 80% of women will have normal glucose tolerance after a pregnancy. It is worth remembering that of the 20% where glucose tolerance does not return to normal some would have had undiagnosed diabetes or impaired glucose tolerance prior to their pregnancy.

Where do I get my needles and insulin? Is it expensive?

In Australia you will register with the NDSS when you are diagnosed with gestational diabetes. This will allow you to access a subsidised cost for your blood testing strips. If insulin is required your registration will be upgraded to state you need insulin. You then can access the supplies you need from your local diabetes friendly chemist. Insulin needles are free. For those holding valid Medicare registration, insulin is quite cheap! For the cost of 1 standard script (about $35) you will get 25 insulin devices!- often more than you will need the entire pregnancy. For those without Medicare in Australia you may be able to claim costs back from your private health insurer. For those of you in countries other than Australia please ask your doctor or diabetes educator for more information.

Is there anything I need to know about storing insulin?

Insulin should be kept refrigerated prior to your obtaining it. Once you are using your device it shouldn’t remain in the fridge, however the others you are not yet using should be kept in the fridge. Insulin should not be kept in hot places i.e. in the car or in direct sunlight etc.

For additional information to help you better manage your blood glucose levels and nutrition, read our fact sheet on Eating well with and How to snack right for gestational diabetes. 

Last updated October 2012.

  • Fizzy says:

    Thanks so much for this! I was told yesterday that I am going to have to go on insulin for the last few weeks of my pregnancy. I didn’t have a lot of questions then, because I was a bit taken aback, but when I got home, my head was filled with questions! You answered a lot of them.
    Thank you.

    • Lisa says:

      Hi Fizzy. We’re so glad this article helped. Sometimes the hardest part is knowing what you don’t know right? If there are any other questions you’d like us to add here, please let us know. Thanks. Lisa x

  • Lisa says:

    Hi Rebecca. Here is a response from Natasha (our in-kitchen dietitian/ diabetes educator). She has said that the nighttime slow release insulin isn’t working on the food you eat, so it doesn’t matter whether you have a snack before or after taking your insulin. Generally it’s suggested having something of about 1 carb serve at nighttime – but the choice is up to you. It could be a piece of toast, a piece of fruit, a tub of yoghurt or a glass of milk- whatever your preference is. Cheers, Lisa

  • Lauren says:

    Thank you for this article (and the other questions and answers). I found it very helpful and informative. I only have to take nighttime insulin but it really did make me feel like a failure of a vessel even though I’m very conscientious about diet and exercise. This whole experience has been incredibly educating, and I’m so thankful for your website! Invaluable.

  • Sujeewa says:

    The details that are written here is more valuable for me, thank you so much I got a good knowledge about having insulin in my pregnancy

    Thank you again

  • Lisa says:

    Hi Mez. Thanks for your question. In Australia, pregnant women are tested anytime from around week 26/28 (if they have no risk factors for GDM). This might sound late in the picture, however at this time your hormone levels are much higher than they were earlier in the pregnancy and are more likely to interfere with your body’s ability to process glucose. Diagnosis at this stage still allows time to manage and control your baby’s growth and wellbeing. If you are at-risk then you’ll probably be tested much earlier on. We have more info here Cheers, Lisa x

  • Sarah K. Scott says:

    Hi, I really found your article very helpful and informative. Thanks for sharing this. It has a great impact to those people who has a diabetic problems.

  • Cas says:

    Such useful information, thank you! I was so upset when I found out I have GD, and I have now been told I will have to go on insulin. As someone who is on the very low end of the average weight spectrum, a daily exerciser and a healthy eater, I was very surprised to find I have GD – I’m not in any of the risk groups! Reading this made me feel more normal. And I’m hoping my comment makes others like me feel a bit more “normal”.

  • Trina Cruz says:

    22 weeks with gestational. …. and on insulin 3times a day. Thanks for the info

  • Kimberley says:

    Hi there! Thank you so much for this excellent information. You answered sooo many of my questions. I’ve been taking insulin now for about two weeks and I must say, my blood sugar levels have been right on target. However, I still found this posting added to my comfort with taking insulin even after listening to my doctor and diabetes educator.

  • Patricia Holloway says:

    My daughter has just been told she needs to take insulin. We are concerned because they are not referring her to an Endocrinologist the dietician is handling it and she is talking to the Endocrinoligist. Is that normal practice or should a specialist be involved. Thanks for your website it has been so so helpful it is hard to get answers. Trisha

    • Lisa says:

      Hi Trisha. Management for diabetes can vary from hospital to hospital, so perhaps this is the way they do things at your daughter’s hospital. Is there a particular reason you want to see the endocrinologist and is it something you feel the dietitian can’t help you with? In most cases, these two health practitioners will be working hand in hand to manage your daughter’s wellbeing. But this is a time when your daughter doesn’t need extra stress, so if you think it will really help, you should persist and get her to see the endo. How does that sound? Thanks so much for getting in touch. Lisa x

  • Lisa says:

    Hi Anusha. Thanks for your message. Taking insulin is a really safe way to manage your diabetes and won’t impact the way you deliver your baby. One of the ways that is impacted is if your baby is large and the doctors think they need to intervene. We have an article with lots of answers about insulin. Take a look Best wishes, Lisa x

  • Lisa says:

    Hi Kimberly. How are you getting on? I had missed your comment back in November. I hope it’s all going well. Lisa x

  • Shalini says:

    Hi! thank you for your article, very useful. My question – I am taking low doses of insulin before lunch and before dinner. I know that with insulin I cannot really eat back to my “normal” lots of carbs. But once in a while I do :(, like last night and my sugar level was high at 167 two hours after dinner. Is this a concern? If I do have high sugar levels once or twice a week? Past 8 days my levels are controlled i.e. <95 for fasting, and below 120 after 2 hours of lunch and dinner. But two readings show 167. I will be checking with doctor, but that is next week. thank you again – Shalini

    • Lisa says:

      Hi Shalini. Natasha Leader (our in-house dietition) provided this response for you. “Ideally glucose spikes are minimised. If you get a higher reading it’s best to reflect on what may have caused elevation i.e. quantity or type of carb or high saturated fat meal etc. If you know ahead of time that you are eating a bigger meal etc. then it is a good idea to speak to your doctor about a temporary dose. Insulin doses need regular adjustment during pregnancy in any case.” Hope that helps. Lisa x

  • Aejay says:

    Hi Lisa!

    I’m so happy to find your website, I just found out that I have GDM yesterday and it’s really stressful and kinda depressing. I’m a nurse and I have some ideas about diabetes but everything’s different if you’re the one who’s experiencing it. I feel scared but you’re helpful website really gives support and more knowledge about GDM. I will be referred to a dietitian and would be glad to do everything needed to stabilize my blood sugar. I will definitely try to incorporate the ideas (recipe) here on your website. Thank you so much for sharing!

    • Lisa says:

      So glad you found us! And best wishes with your pregnancy. We hope you’ve found some delicious ideas within these pages. Lisa x

  • Lisa says:

    Hi Hazeline. Good on your for making an impact with your BGLs. However regarding this questions, you’re best off speaking with your diabetes educator, doctor or a health professional at the hospital about that. Cheers, Lisa x

  • Lauren H says:

    I am so thankful I found this article. I had so many questions but didn’t know what they were, if that makes sense. I’ve felt horrible about needing to take insulin because of gestational diabetes and have resisted it, trying to manage with diet and Metformin alone but I just can’t seem to keep it stable, because of my own behaviors and certain carbs my body just doesn’t like. This article has helped me decide to take the insulin, I think mostly for peace of mind that my baby will be okay and it will be easier to manage in the long run. Thanks again!

  • Michelle says:

    Hi Lisa,

    I myself was diagnosed with GD today and I can’t tell you how stressed I was. so of course I googled to try to get ahead of my nutrition needs before I saw the nutritionist and finding your site was such a god send! Thank you so much!!

Comments are currently closed on this post.


I’m Lisa Taylor, the mum behind GDRecipes. I created this site after having GDM myself & because I love food. I’d like to inspire, motivate & support you to cook & eat well during your pregnancy with GDM & beyond. Come read my story. My kitchen is your kitchen. ... Read more

  • Ingredient search

    Search for recipes by ingredient. Just type your ingredient into the homepage 'Search' box.
  • Getting started

    Getting started with GDM? Check out our 'Eating Well' section for tips on eating right & staying on track. Can you have your cake and eat it too? Find out.
  • First Testimonial

    'I know what you ate last summer...& it didn't give you GDM'. What are some of the myths about getting GDM? Find out in our article.
  • Second Tesimonial

    Don't forget to add your comments to recipes, articles & interviews. My kitchen is your kitchen. I want to hear your thoughts.