Pregnancy comes with its fair share of challenges in terms of physical and emotional changes. When coupled with type 1 diabetes (T1D), pregnancy also affects blood sugar management and maternal and fetal health.
Certain risks may be increased for both the mother (e.g., more frequent hypoglycemia, premature delivery, high blood pressure) and the baby (e.g., malformations, premature birth, hypoglycemia at birth) if blood sugar levels are not optimally managed before and during pregnancy.
Fortunately, these risks are greatly reduced with adequate planning and preparation. By following the recommendations below, you’ll have the best chance of having a complications-free pregnancy and giving birth to a healthy baby.
Preparation is the key
If you’re thinking about getting pregnant, here are some important steps to take to prepare your body and optimize your health:
- Consult with your healthcare team BEFORE you start. They’ll be able to assess your current health status, to help you develop an individualized care plan and to validate your treatment with you. Some medications aren’t safe during pregnancy and will need to be stopped.
- Optimize your blood sugar levels. Blood sugar management is crucial to a healthy pregnancy. It’s recommended to reach a glycated hemoglobin (HbA1c) level under or equal to 7.0% before conception and to ideally aim for 6.0%. You may need to adjust your insulin doses. Your healthcare team can help you achieve this goal. If your HbA1c is greater than 10.0%, you’ll need to delay your pregnancy until targets are met.
- Adopt a healthy lifestyle. Since pregnancy can be physically demanding, it’s important to maintain a healthy lifestyle before and during pregnancy. This may include eating a balanced diet, exercising regularly and reducing alcohol and tobacco use. Overweight and obesity can also increase the risk of complications for both mother and child, so it’s recommended to maintain a healthy weight. Discuss the issue with your healthcare team if needed.
- Keep an eye out for diabetes-related complications (with the help of your doctor). Some pre-existing complications (e.g., retinopathy—an eye condition related to diabetes) can sometimes worsen during pregnancy. Therefore, it’s recommended to have these potential complications assessed prior to pregnancy.
- Start taking folic acid tablets (1 mg) three to six months before conception (or as soon as possible if the pregnancy was unplanned). Folic acid helps prevent a complication for the baby called spina bifida in both diabetic and non-diabetic women.
Adjusting your goals
From early pregnancy until delivery, blood sugar targets fluctuate. And since high blood sugar levels can significantly increase risks to the child, they’re also much tighter.
Continuous glucose monitoring (CGM) systems (e.g., Dexcom, Freestyle Libre) can help monitor blood sugar levels more closely. Ever since the COVID-19 pandemic, Health Canada has authorized the use of CGMs during pregnancy. When using a CGM during pregnancy, the recommendations for time in range are to maintain blood sugar levels:
- More than 70% of the time between 3.5 and 7.8 mmol/L;
- Less than 25% of the time above 7.8 mmol/L;
- Less than 5% of the time below 3.5 mmol/L.
How pregnancy impacts blood sugar
Blood sugar levels can be affected not only by the usual nausea and vomiting that are part and parcel of pregnancy, but also by the variety of hormones produced by the placenta.
In early pregnancy, these hormones can decrease the level of glucose produced by the liver and, therefore, increase the risk of hypoglycemia while also reducing the symptoms of low blood sugar. It’s important to be vigilant and adjust insulin doses as needed.
Conversely, later in pregnancy, certain hormones may limit the action of insulin and increase insulin resistance. As the placenta grows, more of these hormones are produced and insulin resistance keeps increasing, which raises blood sugar.
Right after delivery, the hormones produced by the placenta no longer have any effect, which reduces the amount of insulin needed.
If you decide to breastfeed, the risk of hypoglycemia may also be increased during or after a feeding. You’ll need to check your blood sugar more frequently and eat snacks as needed. A nutritionist will be able to help you define a food plan to reach your goals.
In conclusion, with proper planning and monitoring, women with T1D can have an uncomplicated pregnancy and deliver a healthy baby.
If you have any concerns, don’t hesitate to talk to your healthcare team and to other women with T1D who have experienced pregnancy; it will help you feel more confident and better understand the potential challenges.
- Vargas, Roberto et al. “Type 1 diabetes mellitus and pregnancy.” Reviews in obstetrics & gynecology vol. 3,3 (2010): 92-100.
- Holt, Richard I G et al. “The management of type 1 diabetes in adults. A consensus report by the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD).” Diabetologia vol. 64,12 (2021): 2609-2652. doi:10.1007/s00125-021-05568-3
- Cours « Tout sur la grossesse », Plateforme Support-T en cours de développement, Projet BETTER
- Diabetes Care 2023;46(Suppl. 1):S254–S266 | https://doi.org/10.2337/dc23-S015
- Sarah Haag RN. BSc.
- Amélie Roy-Fleming Dt.P., EAD, M.Sc.
- Claude Laforest, Jacques Pelletier, Michel Dostie, Marie-Christine Payette, Nathalie Kinnard, patient partners of the project
Linguistic revision by: Marie-Christine Payette
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