Gestational Diabetes
- Did you know that one form of diabetes only appears during pregnancy? The medical name for it is gestational diabetes mellitus (GDM).
- Between three to 20 percent of pregnancies are affected by gestational diabetes. (could use a visual for this - 3 to 20 out of 100)
- Once the baby is born, the diabetes usually goes away. However, you may develop another form of diabetes later in life.
If you are pregnant, you may be surprised to learn that you are at risk of developing a form of diabetes that appears only during pregnancy. Gestational diabetes mellitus (GDM) affects between three to 20 per cent of pregnancies, depending on risk factors. If you do have it, caring for your health is essential both for you and for your unborn baby.
Almost everything we eat is digested into glucose (sugar), which goes into the blood. Insulin, made by the pancreas, helps glucose move from the bloodstream into the body’s cells to be used as fuel.
During pregnancy, the placenta releases hormones that block the action of insulin in the body. Many pregnant people produce enough extra insulin on their own, so this is not a problem. However, if there is not enough insulin to deliver the fuel, high amounts of glucose remain in the blood.
If you have gestational diabetes, it is not your fault. However, since leaving too much glucose in the blood causes problems, you will need to care for yourself differently.
How is gestational diabetes diagnosed?
Since GDM may have no symptoms, it is recommended that anyone who is pregnant should be tested between 24 and 28 weeks of pregnancy. Your doctor will order this screening test, which is done in a lab. You will first be given a very sweet glucose drink. One hour later, a blood sample will be drawn from your arm. A positive test shows that you have a high level of glucose in your blood.
If the level is slightly high, another blood test may be needed. More blood will be drawn before and after you have an even sweeter drink to see how your body deals with a greater glucose challenge. After the second test, a definite diagnosis can be made.
What happens if I have gestational diabetes?
If your diagnosis is positive, you will be referred to a doctor who specializes in GDM. This doctor and a team of health care providers work with you to manage the diabetes. You will learn how to check your capillary blood glucose (CBG) levels to monitor your blood glucose at home. This check must be done four times per day, generally before breakfast and after meals. You will be told how long after meals to check your blood glucose.
More studies are needed on the benefit of continuous glucose monitoring (CGM) in those with gestational diabetes. Recommended CGM targets are not yet known.
Keeping a record of your blood glucose numbers will help you and your diabetes team. The home blood glucose numbers that contribute to a healthy pregnancy are:
(before breakfast) | under 5.3 mmol/L |
One hour after meals | under 7.8 mmol/L |
Two hours after meals | under 6.7 mmol/L |
If you use insulin, aim to keep the number over 3.7 mmol/L.
How do I manage my blood glucose numbers?
Blood glucose is affected by how and what you eat. When you eat too much at once, it is hard for the pancreas to make enough insulin. To help your own insulin work more efficiently, it is better to eat small amounts more often. As part of your diabetes team, a registered dietitian works with you to create a meal plan. You will be given a three-meal and three-snack plan to help control your insulin levels. Sometimes, a short walk after meals is suggested to help keep blood glucose levels lower.
What if my blood glucose is still over the limit?
If diet and lifestyle changes cannot control your blood glucose, you may need insulin injections. Although most diabetes medications cross the placenta to the baby, insulin does not. You will be given an insulin pen (needle) and taught how to use it. This may sound scary, but is actually very easy to do. Insulin doses are calculated based on your daily blood glucose readings. Don’t worry – you will have help in learning about this process. You will be asked to test your urine for ketones. When the body is not getting enough food in the form of glucose, the breakdown of fat creates ketones. You will use ketone test strips, available from your pharmacy, to test your urine each morning. If ketones do appear, your meal plan or your amount of insulin will be adjusted.
What if I ignore this whole scary-sounding thing?
High levels of glucose in your blood can make your baby grow larger, and make giving birth more difficult. Preeclampsia (high blood pressure that occurs during pregnancy) may occur. The baby may not develop normally and could have problems, much like a premature baby might. With totally uncontrolled diabetes, there is a higher risk of a stillbirth. You and your baby may have a higher risk of health problems later in life, such as type 2 diabetes and heart disease.
If this feels overwhelming, remember that you are not alone. Your diabetes team will give ongoing support and teaching throughout your pregnancy. Happily, good blood glucose control usually results in a healthy pregnancy and baby.
Who is at risk?
You may have a higher chance of developing gestational diabetes if you:
- have prediabetes
- had gestational diabetes with a previous pregnancy
- are over age 35
- are obese (with a BMI of 30 or more)
- have a history of polycystic ovary syndrome
- are a member of a higher-risk ethnic group (African, Arab, Asian, Hispanic, Indigenous, or South Asian)
- have given birth to a baby that weighed more than 4 kg (8.8 pounds)
- have a parent, brother or sister with type 2 diabetes
- have darkening of the skin (acanthosis nigricans) in certain areas of your body
- use corticosteroid medication for chronic illness.
Does gestational diabetes mean my baby and I will have diabetes forever?
Your baby will not be born with diabetes. However, since this condition is hereditary, it is possible that your baby might develop diabetes later in life. Nursing shortly after birth and for at least four months is encouraged to help avoid low blood glucose in your newborn. It also reduces your baby’s risk of obesity and diabetes.
For the parent, diabetes typically goes away. Six weeks after delivery, you will have another blood test to make sure your blood glucose has returned to normal. However, your risk of developing diabetes down the road is much higher – as much as 60 per cent. It is important that you have a blood glucose check done yearly.
I had gestational diabetes. What can I do to prevent developing diabetes in the future?
A healthy lifestyle and staying in a healthy weight range can improve your chances of avoiding diabetes. Health Canada suggests spending at least 150 minutes per week doing an activity. Walking is a simple and inexpensive way to stay active after pregnancy. You can even take your baby with you!
- Wear runners or good walking shoes and start with 30 minutes, three days a week. Build up to 30 minutes, five days a week.
- Don’t stop for the winter – try a gym, get your own treadmill or stationary bike or join the mall walkers.
- Add resistance to your activity. For instance, use two-pound Velcro weights, one strapped to each wrist. These are available anywhere sports equipment is sold.
- Always talk to your doctor before trying any strenuous activity.
- Nutrition is also important. When you skip meals, the body’s metabolism slows down to deal with the reduced amount of fuel.
- Try eating smaller amounts more often to keep your metabolism working efficiently and steadily.
- Limit eating out and high-fat meals.
- Rather than frying food, try baking, barbequing, broiling or using a crockpot. Include fruits and vegetables with every meal and most snacks.
Diabetes Canada has a variety of resources in the Nutrition and Fitness section of their website. You can also use the search “gestational diabetes” to find details on diabetes in pregnancy.
While learning that you have gestational diabetes may come as a shock, know that you can handle it. Your healthcare team is available to help you along the way. The end result – your healthy baby – is worth the challenge of dealing with gestational diabetes.
WRITTEN BY: Candice Gale Slobodian, RN, CDE.
UPDATED BY: Aniket Paria, RPh, APA, CDE, a pharmacist in Medicine Hat, AB.